Vaisala Drycap DMT152 Operation & User’s Manual

P.O. Box 26 Fax: +358 9 8949 2227 FIN-00421 Helsinki Finland Visit our Internet pages at http://www.vaisala.com/ © Vaisala 2008 No part of this manual may be reproduced in any form or by any means, electronic or mechanical (including photocopying), nor may its contents be communicated to a third party without prior written permission of the copyright holder. The contents are subject to change without prior notice. Please observe that this manual does not create any legally binding obligations for Vaisala towards the customer or end user. All legally binding commitments and agreements are included exclusively in the applicable supply contract or Conditions of Sale.

Table of Contents CHAPTER 1 GENERAL INFORMATION............................................................................ 5 About This Manual ................................................................... 5 Contents of This Manual ....................................................... 5 Version Information............................................................... 6 Related Manuals ................................................................... 6 General Safety Considerations ............................................. 6 Feedback............................................................................... 6 Product Related Safety Precautions ...................................... 7 Recycling .................................................................................. 7 Regulatory Compliances ......................................................... 7 Trademarks............................................................................... 7 Warranty.................................................................................... 8 CHAPTER 2 PRODUCT OVERVIEW.................................................................................. 9 Introduction to Dewpoint Transmitter DMT152..................... 9 Basic Features and Options.................................................. 10 Transmitter Structure............................................................. 10 CHAPTER 3 FUNCTIONAL DESCRIPTION..................................................................... 13 Advanced DRYCAP® Technology......................................... 13 Auto-Calibration .................................................................. 13 Sensor Purge ...................................................................... 14 Sensor Warming ................................................................. 14 CHAPTER 4 INSTALLATION............................................................................................ 15 Selecting the Location........................................................... 15 Installing the Transmitter ..................................................... 16 Wiring ...................................................................................... 18 Connection Cables.............................................................. 19 Power Supply Requirements............................................... 20 Sampling from a Process ...................................................... 21 Pressure......................................................................... 21 Leak tightness and materials ......................................... 21 Flow................................................................................ 22 Sampling Cell Types .............................................................. 22 DMT242SC Sampling Cell .................................................. 22 DMT242SC2 Sampling Cell with Swagelok Connectors .... 22 DSC74 Sampling Cell with Quick Connector and Leak Screw.......................................................................... 23

2 ___________________________________________________________________ M210865EN-D DSC74B Two Pressure Sampling Cell................................24 DSC74C Two-Pressure Sampling Cell with Coil............26 CHAPTER 5 OPERATION.................................................................................................29 Serial Communication............................................................29 Connecting to the Serial Interface.......................................29 Installing the Driver for the USB Cable ..........................29 Terminal Application Settings..............................................30 List of Serial Commands .......................................................32 Device Information and Status..............................................33 Show Device Information ....................................................33 Show Transmitter Status .....................................................34 Show Firmware Version ......................................................34 Configuring Analog Outputs .................................................35 Limit Alarm...........................................................................36 Self-Diagnostic Alarm..........................................................37 Malfunction Alarm................................................................38 Select Analog Output Quantity and Scaling........................38 Configuring Serial Line Operation........................................39 Set Serial Line Settings .......................................................39 Set Serial Line Response Time...........................................39 Set Transmitter Address......................................................40 Format the Measurement Output ........................................40 Select Unit ...........................................................................42 Set Serial Interface Mode....................................................42 Configuring Measurement Parameters ................................43 Enable or Disable Sensor Purge.........................................43 Set Pressure Value for ppm Calculation .............................43 Set Molar Mass for ppmw Calculation.................................45 Serial Line Output Commands..............................................45 Start Measurement Output..................................................45 Stop Measurement Output ..................................................46 Set Output Interval...............................................................46 Output a Reading Once.......................................................47 Troubleshooting and Maintenance Commands ..................47 Display the Currently Active Errors .....................................47 Test Analog Outputs............................................................47 Calibrate Analog Output......................................................48 Extend Analog Output Range..............................................49 Other commands ....................................................................49 Opening the Transmitter in POLL Mode .............................49 Closing the Connection to a Transmitter in POLL Mode.....50 Display Command List ........................................................50 Set Time ..............................................................................50 Reset Transmitter................................................................51 Restore Factory Settings.....................................................51 CHAPTER 6 MAINTENANCE............................................................................................53 Cleaning the Transmitter .......................................................53

Changing the Filter................................................................. 53 Calibration and Adjustment .................................................. 55 Field Check using DM70..................................................... 55 Troubleshooting..................................................................... 57 Error State........................................................................... 58 Error Codes......................................................................... 59 Unknown Serial Settings..................................................... 60 Technical Support.................................................................. 60 Vaisala Service Centers......................................................... 61 CHAPTER 7 TECHNICAL DATA ...................................................................................... 63 Measured Variables................................................................ 63 Operating Environment ......................................................... 63 Outputs.................................................................................... 64 General .................................................................................... 64 Output Cable Specifications ................................................. 65 Spare Parts and Accessories................................................ 65 Dimensions in mm (inches) .................................................. 66

4 ___________________________________________________________________ M210865EN-D List of Figures Figure 1 Dewpoint Transmitter DMT152.................................................11 Figure 2 DMT152 Installed Directly to Pipeline ......................................16 Figure 3 Removing the Transport Protection Cap..................................16 Figure 4 Installing the Transmitter ..........................................................17 Figure 5 Connecting the Cable...............................................................17 Figure 6 Connectors I and II ...................................................................18 Figure 7 Connector Pinout......................................................................19 Figure 8 Cable with Snap-On Connector................................................20 Figure 9 Cable with Threaded Connector...............................................20 Figure 10 Sampling Cells DMT242SC2 (left) and DMT242SC (right) ......23 Figure 11 DSC74 Sampling Cell with Accessories...................................24 Figure 12 DSC74B....................................................................................25 Figure 13 Removing the Leak Screw........................................................25 Figure 14 Default Assembly of DSC74C ..................................................26 Figure 15 Alternative Assembly of DSC74C (for Tight Spaces)...............27 Figure 16 PuTTY Terminal Application.....................................................31 Figure 17 Filter Structure ..........................................................................54 Figure 18 Supply Voltage Too Low for mA Output Error..........................56 Figure 19 DMT152 Dimensions................................................................66 List of Tables Table 1 Manual Revisions .......................................................................6 Table 2 Related Manuals.........................................................................6 Table 3 Quantities Measured by the DMT152.........................................9 Table 4 DMT152 Default Serial Interface Setting..................................30 Table 5 DMT152 Serial Commands ......................................................32 Table 6 FORM Command Quantities ....................................................41 Table 7 FORM Command Modifiers......................................................41 Table 8 Pressure Conversion Coefficients ............................................44 Table 9 Error codes ...............................................................................59

VAISALA ________________________________________________________________________ 5 CHAPTER 1 GENERAL INFORMATION This chapter provides general notes for the manual and the Dewpoint Transmitter DMT152. About This Manual This manual provides information for installing, operating, and maintaining Dewpoint Transmitter DMT152. Contents of This Manual This manual consists of the following chapters: - Chapter 1, General Information, provides general notes for the manual and the Dewpoint Transmitter DMT152. - Chapter 2, Product Overview, introduces the features and advantages of Dewpoint Transmitter DMT152. - Chapter 3, Functional Description, describes the advanced functionality of Dewpoint Transmitter DMT152, including the auto-calibration, sensor purge and sensor warming functions. - Chapter 4, Installation, provides you with information that helps you install the Dewpoint Transmitter DMT152. - Chapter 5, Operation, contains the operating instructions and serial line commands for the Dewpoint Transmitter DMT152. - Chapter 6, Maintenance, provides information on the maintenance of Dewpoint Transmitter DMT152. - Chapter 7, Technical Data, provides the technical data of Dewpoint Transmitter DMT152.

6 ___________________________________________________________________ M210865EN-D Version Information Table 1 Manual Revisions Manual Code Description M210865EN-A March 2008 – First version. M210865EN-B July 2008 – Changed default serial line mode. Added instructions for field checking with DM70. Added troubleshooting instructions. M210865EN-C August 2008 – Updated analog output ranges. M210865EN-D October 2008 – Revised instructions for alarm configuration in chapter 5. Related Manuals Table 2 Related Manuals Manual Code Manual Name M210866EN-A Vaisala DRYCAP® Dewpoint Transmitter DMT152 Quick Reference Guide General Safety Considerations Throughout the manual, important safety considerations are highlighted as follows: WARNING Warning alerts you to a serious hazard. If you do not read and follow instructions very carefully at this point, there is a risk of injury or even death. CAUTION Caution warns you of a potential hazard. If you do not read and follow instructions carefully at this point, the product could be damaged or important data could be lost. NOTE Note highlights important information on using the product. Feedback Vaisala Customer Documentation Team welcomes your comments and suggestions on the quality and usefulness of this publication. If you find errors or have other suggestions for improvement, please indicate the chapter, section, and page number. You can send comments to us by e-mail: [email protected]

VAISALA ________________________________________________________________________ 7 Product Related Safety Precautions The Dewpoint Transmitter DMT152 delivered to you has been tested for safety and approved as shipped from the factory. Note the following precautions: CAUTION Do not modify the unit. Improper modification can damage the product or lead to malfunction. Recycling Recycle all applicable material. Dispose of batteries and the unit according to statutory regulations. Do not dispose of with regular household refuse. Regulatory Compliances Vaisala DRYCAP® Dewpoint Transmitter DMT152 is in conformity with the following EU directives, including the latest amendments, and with national legislation implementing these directives: - EMC-Directive (2004/108/EC) - RoHS-Directive (2002/96/EEC) The conformity is shown by compliance with the following standards: - EN 61326-1:1997 + A1:1998 + A2:2001 + A3:2003, Electrical equipment for measurement, control and laboratory use - EMC requirements - industrial environment. - CISPR 22: 2006 Class B, EN 61000-4-2: 2001, EN 61000-4-3: 2002, EN 61000-4-4: 2004, EN 61000-4-5: 2001, EN 61000-4-6: 2003 - EN 50419 (2005-01) Trademarks DRYCAP® is a registered trademark of Vaisala.

8 ___________________________________________________________________ M210865EN-D Warranty Vaisala hereby represents and warrants all Products manufactured by Vaisala and sold hereunder to be free from defects in workmanship or material during a period of twelve (12) months from the date of delivery save for products for which a special warranty is given. If any Product proves however to be defective in workmanship or material within the period herein provided Vaisala undertakes to the exclusion of any other remedy to repair or at its own option replace the defective Product or part thereof free of charge and otherwise on the same conditions as for the original Product or part without extension to original warranty time. Defective parts replaced in accordance with this clause shall be placed at the disposal of Vaisala. Vaisala also warrants the quality of all repair and service works performed by its employees to products sold by it. In case the repair or service works should appear inadequate or faulty and should this cause malfunction or nonfunction of the product to which the service was performed Vaisala shall at its free option either repair or have repaired or replace the product in question. The working hours used by employees of Vaisala for such repair or replacement shall be free of charge to the client. This service warranty shall be valid for a period of six (6) months from the date the service measures were completed. This warranty is however subject to following conditions: a) A substantiated written claim as to any alleged defects shall have been received by Vaisala within thirty (30) days after the defect or fault became known or occurred, and b) The allegedly defective Product or part shall, should Vaisala so require, be sent to the works of Vaisala or to such other place as Vaisala may indicate in writing, freight and insurance prepaid and properly packed and labelled, unless Vaisala agrees to inspect and repair the Product or replace it on site. This warranty does not however apply when the defect has been caused through a) normal wear and tear or accident; b) misuse or other unsuitable or unauthorized use of the Product or negligence or error in storing, maintaining or in handling the Product or any equipment thereof; c) wrong installation or assembly or failure to service the Product or otherwise follow Vaisala's service instructions including any repairs or installation or assembly or service made by unauthorized personnel not approved by Vaisala or replacements with parts not manufactured or supplied by Vaisala; d) modifications or changes of the Product as well as any adding to it without Vaisala's prior authorization; e) other factors depending on the Customer or a third party. Notwithstanding the aforesaid Vaisala's liability under this clause shall not apply to any defects arising out of materials, designs or instructions provided by the Customer. This warranty is expressly in lieu of and excludes all other conditions, warranties and liabilities, express or implied, whether under law, statute or otherwise, including without limitation any implied warranties of merchantability or fitness for a particular purpose and all other obligations and liabilities of Vaisala or its representatives with respect to any defect or deficiency applicable to or resulting directly or indirectly from the Products supplied hereunder, which obligations and liabilities are hereby expressly cancelled and waived. Vaisala's liability shall under no circumstances exceed the invoice price of any Product for which a warranty claim is made, nor shall Vaisala in any circumstances be liable for lost profits or other consequential loss whether direct or indirect or for special damages.

VAISALA ________________________________________________________________________ 9 CHAPTER 2 PRODUCT OVERVIEW This chapter introduces the features and advantages of Dewpoint Transmitter DMT152. Introduction to Dewpoint Transmitter DMT152 The Vaisala DRYCAP® dewpoint transmitter DMT152 measures dewpoint temperature accurately in a measurement range from -80 ºC to -30 ºC (-112 … -22 °F). The maximum output range of the transmitter is -100 … +20 °C (-148 … +68 °F). If the primary dewpoint measurement range of the application is above -30 °C (-22 °F), other Vaisala transmitters may be more suitable. The DMT152 is designed for a wide range of OEM applications. The transmitter is easy to install, and the mechanics have been designed for harsh environments requiring protection against dust, dirt and splashed water. The excellent stability and reliability of the transmitter’s performance is based on advanced DRYCAP® polymer sensor technology. The DRYCAP® technology has low maintenance needs due to its excellent long term stability and durability against condensation. For more information on DRYCAP® technology, refer to chapter Functional Description on page 13. Table 3 Quantities Measured by the DMT152 Quantity Abbreviation Metric Unit Non Metric Unit Dewpoint/frost point temperature TDF ºC ºF Parts per million H2O ppmv/ ppmw ppmv/ ppmw

10 __________________________________________________________________ M210865EN-D Basic Features and Options - Calibrated dewpoint measurement range -80 ... -30 °C Td, output range -100 ... +20 °C Td - Output in Td* and ppm - DRYCAP® polymer sensor with auto-calibration and sensor purge ensures long term stability - Sensor warming keeps the sensor dry in abnormally high humidity situations - Small size to fit in tight installations - Two analog output channels, selectable from 0 … 20 mA / 4 ... 20 mA and 0 … 5 V / 0 … 10 V - Configurable alarm modes for analog outputs - Digital output: RS-485 - Serial line connection also via USB serial interface cable (Vaisala order code 219690) - Simultaneous use of analog and digital output possible - Low maintenance requirements due to excellent long term stability - Field check suitability with DM70 hand-held meter - Optional sampling cells with different installation options available as DMT152 installation accessories *When the dewpoint is below 0 °C, the transmitter outputs frostpoint for Td Transmitter Structure The structure of the DMT152 is shown in Figure 1 on page 11. The transmitter body does not have user serviceable parts inside, and is not designed to be opened. Opening the transmitter will void the warranty. When the transmitter is delivered, the filter is protected by a yellow transport protection cap that keeps the sensor dry. The transport protection cap should be left on the transmitter during storage. Remove the transport protection cap before installing the transmitter.

VAISALA _______________________________________________________________________ 11 0710-151 Figure 1 Dewpoint Transmitter DMT152 where 1 = 4-pin M8 connector I: analog output channels and operating power 2 = 4-pin M8 connector II (shown with protective cap): digital output (RS-485) and operating power 3 = 30mm nut 4 = DRYCAP® sensor protected with stainless steel mesh filter (see Figure 17 on page 54) 5 = Connection thread: ISO G1/2", UNF 3/4"-16 2A, or NPT 1/2" When installing a DMT152 transmitter with ISO or UNF thread, use a sealing ring to achieve a tight installation. Three copper sealing rings are provided with the transmitter, and more can be ordered from Vaisala. Note that the sealing rings for ISO and UNF threads are different. See section Spare Parts and Accessories on page 65. NOTE Do not use a sealing ring with the NPT thread. Instead, seal the thread using PTFE tape or PTFE paste sealant.

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VAISALA _______________________________________________________________________ 13 CHAPTER 3 FUNCTIONAL DESCRIPTION This chapter describes the advanced functionality of Dewpoint Transmitter DMT152, including the auto-calibration, sensor purge and sensor warming functions. Advanced DRYCAP® Technology Dewpoint Transmitter DMT152 utilizes an advanced, patented measurement technology to ensure accurate measurement with excellent long term stability. This results in very low maintenance requirements for the transmitter. The lasting performance is achieved with microprocessor technology and software that automatically performs self-diagnostic functions in addition to the normal dewpoint measurement. The self-diagnostic procedures that are conducted are called auto-calibration, sensor purge and sensor warming. Auto-Calibration The auto-calibration feature of the DMT152 transmitter is an automatic procedure which greatly reduces the possible drift in the dry end of the dewpoint measurement. The auto-calibration is performed: - at 45 minute intervals - when the transmitter is powered up - when the measured environment changes rapidly During auto-calibration the sensor is warmed for a short period (< 1 min) and the sensor capacitance values are evaluated at the elevated temperature. The possible dry end drift is then corrected to correspond to the calibrated values. During the auto-calibration the

14 __________________________________________________________________ M210865EN-D transmitter outputs the Td value that was measured prior to the procedure. When the auto-calibration is done, normal measurement and output is resumed. Auto-calibration is carried out only if several criteria for the measurement environment are fulfilled. This ensures the reliability of the adjustments, and maintains the excellent long term stability that the patented technology offers. Sensor Purge Sensor purge is also an automatic procedure that minimizes the drift at the wet end readings of the dewpoint measurement. Sensor purge is performed once a week or when the power is switched on. The sensor is heated for several minutes which will then evaporate all excess molecules out of the sensor polymer. This, together with the auto- calibration, results in a very small drift. Due to the very linear behavior of the polymer technology, corrections made at the dry end and the wet end correct the reading in the whole range. Sensor Warming The DRYCAP® sensor of the DMT152 transmitter is warmed, which prevents the sensor and filter from becoming wet in high humidities. High humidity may be present when the dewpoint temperature rises close to the gas temperature. The advantage of sensor warming is the rapid response of dewpoint measurement. A wet sensor and filter would otherwise result in a dewpoint equal to ambient temperature (that is RH = 100 %). If the sensor gets soaked, it will recover fully back to normal operation after it dries out.

VAISALA _______________________________________________________________________ 15 CHAPTER 4 INSTALLATION This chapter provides you with information that helps you install the Dewpoint Transmitter DMT152. Selecting the Location It is important that the conditions at the point of installation represent well the gas to be measured. Temperature changes do not affect the dewpoint measurement, but pressure changes will have an effect on the measurement. All leaks in the system must be eliminated to avoid ambient humidity affecting the measurement. Direct installation to the measured gas is the recommended installation method if the temperature of the gas is suitable for DMT152 and no additional filtering is needed due to very dusty or oily gas. Oil as such is not harmful for the DRYCAP® sensor, but response time may be slowed down if there are oil particles in the system, or if oil is collected to the filter over a longer period of time. The maximum measurement pressure is 50 bara / 725 psia (absolute pressure) for direct measurement. If the gas temperature is higher than the specified maximum operating temperature of the transmitter, gas sampling and cooling it to ambient temperature (e.g. 10 °C / 18 °F) is recommended. Note that the dewpoint temperature must be clearly lower than the ambient temperature to avoid condensation in the sampling line. Sampling from the process is easy by using Vaisala sampling cell options; see section Sampling from a Process on page 21. The DMT152 is light in weight which means that it can be installed in a sample pipeline in the sampling cells without the need of any additional mechanical support.

16 __________________________________________________________________ M210865EN-D Max 50 bar 0710-101 Figure 2 DMT152 Installed Directly to Pipeline Installing the Transmitter After selecting a suitable measurement location, follow the procedure below to install the transmitter: 1. Remove the yellow transport protection cap from the transmitter. Do not touch the filter with your hands. 0710-128 Figure 3 Removing the Transport Protection Cap 2. Prepare the sealing of the connection: - If the transmitter has a parallel ISO G1/2" thread or UNF 3/4"-16 thread, place the sealing ring at the base of the thread. Always use a new sealing ring; do not re-use a previously installed one. - If the transmitter has an NPT 1/2" thread, do not use the sealing ring. Instead, apply PTFE tape or suitable paste sealant to the thread. Follow the application instructions of the sealant.

VAISALA _______________________________________________________________________ 17 3. Make sure that the threads on the mounting point are of the correct type, and fasten the transmitter to the measurement point. Use your hands to turn the probe until it feels tight. Do not use force at this point, and check that the sealing ring (if used) remains centered. 0710-129 Figure 4 Installing the Transmitter 4. Use a 30mm wrench to tighten the connection to 25 N m, as shown in Figure 4. If you do not have a 30mm wrench, use a 1 3/16” wrench or an adjustable wrench. CAUTION Only tighten the probe from the 30mm nut. Do NOT apply force to other points in the probe body. 5. Connect the wires of the connection cable. When using cables provided with DMT152 refer to the wiring section on page 18. See the power supply requirements on page 20. 0710-130 Figure 5 Connecting the Cable

18 __________________________________________________________________ M210865EN-D 6. Plug in the cable to the transmitter. Be sure to use the correct connector; refer to section Wiring on page 18. 7. Cover the unused connector on the transmitter with the rubber plug that is attached to the transmitter. 8. Turn on the power supply. The DMT152 performs self diagnostics at start-up, and the output is frozen for several minutes. The transmitter will output an approximated reading after one minute, but accurate measurement will only be available after the start-up procedure is complete. Normal operation is typically achieved in 10 … 15 minutes. If the measurement environment changes during the startup, the start-up may take up to 15 minutes. NOTE The transmitter always performs the self-diagnostic procedure and sensor purge when starting up. Keep the transmitter continuously powered to optimize its measurement performance and availability. Wiring Pin I II Wire colour 1 VDC supply+ VDC supply+ Brown 2 Signal Ch 1+ RS-485 - / B White 3 GND GND Blue 4 Signal Ch 2+ RS-485 + / A Black 0707-035 Figure 6 Connectors I and II

VAISALA _______________________________________________________________________ 19 0707-036 Figure 7 Connector Pinout CAUTION The power supply lines are internally connected. You can use either one of them, but do not connect more than one supply voltage in permanent installations. Temporary simultaneous use with the USB serial interface cable or DM70 handheld dewpoint meter (which also provide operation power) is OK. Connection Cables The following connection cable options are available for DMT152: - Unshielded cable with M8 female straight snap-on connector - Shielded cables with M8 female straight threaded connector - USB serial interface cable For the order codes of the cables, refer to section Spare Parts and Accessories on page 65. NOTE Avoid using long cables (over 2m) with voltage output.

20 __________________________________________________________________ M210865EN-D 0510-036 Figure 8 Cable with Snap-On Connector 0510-037 Figure 9 Cable with Threaded Connector Power Supply Requirements The DMT152 transmitters are designed to operate with a supply voltage of 15 ... 28 VDC (voltage output version) or 21 ... 28 VDC (current output version). When only the RS-485 output is used, 11 ... 28 VDC is enough in typical measurement conditions. When measuring in pressures 20 ... 50 bara (290 ... 725 psia) or temperatures -40 ... 0 °C (-40 ... 32 °F), a supply voltage of 21 ... 28 VDC is required. The power supply should maintain the voltage for all load conditions. Current consumption during normal operation is 20 mA. The consumption increases during the sensor self-diagnostics (auto- calibration and sensor purge). The maximum current consumption is 220 mA pulsed current.

VAISALA _______________________________________________________________________ 21 Sampling from a Process Sampling is needed when direct measurement of the air or gas is not possible or desirable. This may be related to, for example, a high process temperature, protecting the sensor from water spikes, the need to easily detach the instrument from a pressurized process without running the whole process down, or wanting to make the measurement at a more convenient location. To get a representative sample of the process gas and avoid error sources caused by the sampling system, the following aspects should be considered: Pressure It is important to keep in mind that changing the pressure of a gas changes the dewpoint temperature of the gas. If the sensor is at a different pressure than the process itself, an error of several tens of degrees dewpoint may be present. You can use the Vaisala Humidity Calculator to simulate the effect of pressure change to dewpoint. The Humidity Calculator can be found at: http://www.vaisala.com/humiditycalculator Leak tightness and materials Due to the typically very low level of humidity, dewpoint measurements are sensitive to ambient moisture leaks. It is therefore important to have a leak tight sampling system construction. The system is likewise sensitive to diffusion of water molecules through the materials, as well as the absorption of moisture into the materials. The piping should preferably be made of metal, e.g. stainless steel with a good surface finish. Hygroscopic materials such as plastics are undesirable and should be avoided. Sample tubing should be as short in length as possible. "Dead ends" should be avoided. Also minimizing the number of connections helps in avoiding leaks. If possible, prepare for measurements by flushing the sampling lines with dry gas.

22 __________________________________________________________________ M210865EN-D Flow Vaisala DRYCAP® sensor is not flow dependent as such. For this reason, the flow of the system is not critical to the measurement, although a higher flow makes the response time faster. Typically a flow of 1-2 l/min (0.035-0.7 ft3/min) is enough. Sampling Cell Types DMT242SC Sampling Cell The DMT242SC is a basic sampling cell with only the main sampling cell body. The inlet and outlet are female threaded sample connectors (inlet G3/8", outlet G1/4" ISO). Refer to Figure 10 on page 23. The DMT242SC is suitable for users requiring only a sampling cell to fit the probe into and doing further assembly (piping into inlet & outlet, valves, possible flow meter) by themselves. DMT242SC2 Sampling Cell with Swagelok Connectors The DMT242SC2 is similar to DMT242SC, but connections are made easy. The sampling cell includes welded swagelok connectors at both the inlet and outlet that fit directly to 1/4" tubing. To fit 6 mm tubing to the connectors, an adapter such as Swagelok® Reducer SS-6M0-R-4 (not supplied by Vaisala) can be used. DMT242SC2 is the suitable choice in e.g. plastics drying systems, where the measurement is made by tapping off the dryer system and bringing a small air stream to the sensor. The swagelok connectors of DMT242SC2 easily connect to a cooling coil or tubing providing the essential function of cooling the dry air to ambient temperature before it reaches the sensor.

VAISALA _______________________________________________________________________ 23 0801-069 Figure 10 Sampling Cells DMT242SC2 (left) and DMT242SC (right) where 1 = Male pipe welded connector Swagelok 1/4" 2 = G1/2" 3 = G1/4" 4 = G3/8" DSC74 Sampling Cell with Quick Connector and Leak Screw The DSC74 has been designed especially for compressed air lines. The sampling cell contains an adjustable leak screw that allows keeping up the pipeline pressure at the sensor. The leak screw is opened and closed with a screwdriver. The leak screw should be 1/2 turn open. This can be verified by first closing the leak screw, then turning 1/2 turn to open it. Then the air coming out will make a barely audible little hiss and it can be lightly felt when putting a hand in front of the air stream. NOTE Do not open the leak screw more than 1/2 turn to avoid reducing the pressure in the sampling cell. The DSC74 comes with a quick connector that fits to industry standard compressed air line connectors (suitable for type D, Quick08, NIP08). This allows for easy installation and detachment of the dewpoint transmitter without having to shut down the process. Alternative ways to connect are through the two different thread

24 __________________________________________________________________ M210865EN-D adapters (G3/8" to G1/2" and G3/8" to G1/4" ISO) that are supplied with each DSC74 unit. When using the DSC74, seal the threads of the quick connector or thread adapter carefully with PTFE thread seal tape. Tighten with a fork spanner. 0507-105 Figure 11 DSC74 Sampling Cell with Accessories where 1 = Thread adapter type G3/8" - G1/2" 2 = Thread adapter type G3/8" - G1/4" 3 = Quick connector 4 = Leak screw 5 = Sampling cell body (DMT242SC) DSC74B Two Pressure Sampling Cell The DSC74B and DSC74C sampling cells are enhanced versions of the DSC74. The body is designed in a way that it is possible to measure at both system pressure and atmospheric pressure. The DSC74B limits the flow rate with a fixed leak screw. The flow is optimized for pressures 3 ... 10 barg. The fixed leak screw eliminates the risk of opening the leak screw fully by accident and this way emptying a gas vessel. The maximum flow can be increased, if needed, by removing the leak screw and adjusting the flow manually with the valve. Harmful gases can be recovered by connecting a collection system at the outlet (not available from Vaisala).

VAISALA _______________________________________________________________________ 25 In the basic operation of the DSC74B, the gas flows to the sensor from the front and the outlet is on the side. To have the measurement done at atmospheric pressure, the inlet and outlet are reversed. Then the reducing parts supplied (G3/8" -G1/2" or G3/8" - G1/4") on the outlet side help to protect the sensor from ambient humidity coming in. DSC74B parts are: - Sampling cell, thread 3/8"G - Connection part with a needle valve and an integrated leak screw - Reducing Nipple (thread adapter), G3/8" - G1/2" - Reducing Adapter (thread adapter), G3/8" - G1/4" 0510-032 Figure 12 DSC74B where 1 = Gas goes in 2 = Gas comes out 0510-033 Figure 13 Removing the Leak Screw

26 __________________________________________________________________ M210865EN-D DSC74C Two-Pressure Sampling Cell with Coil The DSC74C with an outlet coil is designed for the most critical measurements at atmospheric pressure. In the DSC74C the coil is connected to the sampling cell outlet to protect the sensor from ambient humidity disturbing the measurement. The coil can also be used as a cooling coil for sampling from high temperature processes. DSC74C parts are: - Sampling cell, thread G3/8" - Connection part with a needle valve and an integrated leak screw - Reducing Nipple (thread adapter), G3/8" - G1/2" - Reducing Adapter (thread adapter), G3/8" - G1/4" - Diffusion coil (for measurements in atmospheric pressure) 0510-034 Figure 14 Default Assembly of DSC74C where 1 = Gas goes in. The coil can also be used here. 2 = Gas comes out 3 = Coil 4 = Valve

VAISALA _______________________________________________________________________ 27 0403-113 Figure 15 Alternative Assembly of DSC74C (for Tight Spaces) where 1 = Gas comes out 2 = Coil 3 = Thread, max. size 7 mm 4 = Gas goes in 5 = Valve The thread size cannot exceed 7 mm. Use the provided adapter to avoid damage to the probe.

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VAISALA _______________________________________________________________________ 29 CHAPTER 5 OPERATION This chapter contains the operating instructions and serial line commands for the Dewpoint Transmitter DMT152. Serial Communication Connecting to the Serial Interface The DMT152 can be connected to a PC using the RS-485 line on Port II. You can use, for example, the USB serial interface cable (Vaisala order code 219690). The cable also provides operation power to the transmitter from the USB port. It is OK to connect the USB serial interface cable even if the transmitter is already supplied with operation power from another cable. If you have not used the DMT152 USB serial interface cable before, install the driver that came with the cable. Refer to section Installing the Driver for the USB Cable below for detailed instructions. NOTE It is recommended to only connect one USB serial interface cable and DMT152 to a PC. Depending on the USB implementation, your PC may not be able to power more than one DMT152 at a time. Installing the Driver for the USB Cable Before taking the USB cable into use, you must install the provided USB driver on your PC. When installing the driver, you must acknowledge any security prompts that may appear. The driver is compatible with Windows 2000, Windows XP, Windows Server 2003, and Windows Vista.

30 __________________________________________________________________ M210865EN-D 1. Check that the USB cable is not connected. Disconnect the cable if you have already connected it. 2. Insert the media that came with the cable, or download the driver from www.vaisala.com. 3. Execute the USB driver installation program (setup.exe), and accept the installation defaults. The installation of the driver may take several minutes. 4. After the driver has been installed, connect the USB cable to a USB port on your PC. Windows will detect the new device, and use the driver automatically. 5. The installation has reserved a COM port for the cable. Verify the port number, and the status of the cable, using the Vaisala USB Instrument Finder program that has been installed in the Windows Start menu. Windows will recognize each individual cable as a different device, and reserve a new COM port. Remember to use the correct port in the settings of your terminal program. There is no reason to uninstall the driver for normal use. However, if you wish to remove the driver files and all Vaisala USB cable devices, you can do so by uninstalling the entry for Vaisala USB Instrument Driver from the Add or Remove Programs (Programs and Features in Windows Vista) in the Windows Control Panel. Terminal Application Settings The default settings of the DMT152 serial interface are presented in Table 4. If the settings of your DMT152 have been changed and you do not know what they are, refer to section Unknown Serial Settings on page 60. Table 4 DMT152 Default Serial Interface Setting Property Description / Value Baud rate 19200 Parity None Data bits 8 Stop bits 1 Flow control Xon/Xoff (none) The steps below describe how to connect to the DMT152 using the PuTTY terminal application for Windows (available for download at www.vaisala.com) and a USB serial interface cable:

VAISALA _______________________________________________________________________ 31 1. Connect the USB serial interface cable between your PC and the RS-485 port of the DMT152 (port II). 2. Start the PuTTY application. 3. Select the Serial settings category, and check that the correct COM port is selected in the Serial line to connect to field. Note: You can check which port the USB cable is using with the Vaisala USB Instrument Finder program that has been installed in the Windows Start menu. 4. Check that the other serial settings are correct for your connection, and change if necessary. Flow control should be set to None unless you have a reason to change it. 5. Click the Open button to open the connection window and start using the serial line. Note: If PuTTY is unable to open the serial port you selected, it will show you an error message instead. If this happens, restart PuTTY and check the settings. 6. You may need to adjust the Local echo setting in the Terminal category to see what you are typing on the serial line. To access the configuration screen while a session is running, click the right mouse button over the session window, and select Change Settings... from the pop-up menu. 0807-004 Figure 16 PuTTY Terminal Application

32 __________________________________________________________________ M210865EN-D List of Serial Commands All commands can be issued either in uppercase or lowercase. The notation refers to pressing the carriage return (Enter) key on your computer keyboard. Enter a to clear the command buffer before starting to enter commands. NOTE The DMT152 does not output the “>” prompt that is used in the output examples of this manual. The prompt has been added for clarity of the examples. Table 5 DMT152 Serial Commands Command Description ? Show device information ?? Show device information (overrides poll mode) ACAL [1/2] Calibrate analog channel ADDR [0 … 99] Set the transmitter address for POLL mode AERR Set analog output device malfunction error mode ALARM Set analog output limit alarm modes AMODE Set analog output mode AOVER [ON/OFF] Allow analog outputs to exceed their range 10% ASEL Configure analog output quantities and scaling ATEST Test analog outputs CLOSE Close the temporary connection and return the device to POLL mode ERRS Display the currently active errors FORM Change the format of the measurement output FRESTORE Restore factory settings HELP Display the command list INTV [0 … 255 S/MIN/H] Set the continuous output interval (for RUN mode and R command) MOL Set the molar mass of the process gas (used in ppmw calculation) OPEN [0 … 99] Open temporary connection to a device that is in POLL mode PRES Set value for pressure compensation R Start the continuous outputting RESET Reset the transmitter S Stop the continuous outputting SDELAY [0 … 255] Set response sending delay in milliseconds SEND [0 … 99] Output the reading once SERI Set the serial interface settings SMODE [RUN/POLL/STOP] Set the serial interface mode STAT Display transmitter status STATUS Set analog output self-diagnostic alarm TIME Set time for transmitter clock

VAISALA _______________________________________________________________________ 33 Command Description UNIT Select metric or non-metric units VERS Display transmitter software version XPRES Set value for pressure compensation (temporarily, is cleared at reset) XPUR [ON/OFF] Enable or disable sensor purge (temporarily, is enabled at reset) Device Information and Status Show Device Information The ? command outputs a listing of device information. ? Example: >? DMT152/1.10 Serial number : D1930026 Batch number : D1330070 Module number : ???????? Sensor number : C1420000 Cal. date : 20080512 Cal. info : Vaisala/HEL Serial mode : STOP Baud P D S : 19200 N 8 1 Output interval: 1 S Address : 0 Pressure : 1.0132 bar Filter : 1.000 Ch1 output : 0 ... 5 V Ch2 output : U ALARM Ch1 Tdf lo : -80.00 'C Ch1 Tdf hi : 20.00 'C Ch2 Tdf lo : 0.00 'C Ch2 Tdf hi : 0.00 'C If the transmitter is in poll mode, but a connection has not been opened using the OPEN command, issue the ?? command. For a description of the serial interface modes, see section Set Serial Interface Mode on page 42. ??

34 __________________________________________________________________ M210865EN-D Show Transmitter Status The STAT command displays the status of the transmitter in four characters. STAT The status codes are as follows: 0000 Normal measurement 1000 Sensor purge 1010 Settling period after sensor purge 1100 Auto-calibration after sensor purge 1110 Settling period after purge + auto-calibration 0100 Auto-calibration (e.g. after interval has elapsed) 0110 Settling period after auto-calibration 0001 Autocalibration failed (will retry automatically) Example: >stat 0000 > NOTE It is normal for auto-calibration to fail if the measurement environment is changing rapidly; the transmitter will retry the auto- calibration automatically. Auto-calibration should succeed when the environment has stabilized. Show Firmware Version VERS Example: >vers DMT152 / 1.10 >

VAISALA _______________________________________________________________________ 35 Configuring Analog Outputs The DMT152 has two analog output channels. These channels can function either as normal measurement channels, or produce an ON/OFF output if the measurement exceeds a given alarm level (limit alarm) or the transmitter is performing an auto-calibration or purge (self-diagnostic alarm). - In the normal operation mode, a channel outputs voltage or current that corresponds to the reading of the selected quantity. - In the ON/OFF output mode, a channel outputs a specified voltage or current level. This mode is used by the limit alarm and the self- diagnostic alarm. Additionally, DMT152 has a malfunction alarm that is always enabled in normal operation mode. The malfunction alarm can also be enabled for a channel in ON/OFF output mode. See section Malfunction Alarm on page 38. When the transmitter is ordered from Vaisala, the modes are configured as specified in the order form. You can change the operation settings after delivery using the AMODE command: AMODE [c1 c2] where c1 = Channel 1 analog output mode. Available options are: 1 = 0 ... 20 mA 2 = 4 ... 20 mA 4 = 0 ... 5 V 5 = 0 ... 10 V 7 = I alarm (ON/OFF output using current) 8 = U alarm (ON/OFF output using voltage) Modes 1 ...5 are normal measurement modes, where malfunction alarm is always enabled, and limit alarm and self-diagnostic alarm are disabled. c2 = Channel 2 analog output mode. Available options are the same as for channel 1. Example: >amode 2 1 Ch1 output : 4 ... 20 mA Ch2 output : 0 ... 20 mA >

36 __________________________________________________________________ M210865EN-D Limit Alarm The limit alarm is activated when the measured quantity goes below the low limit, or above the high limit. The alarm can be specified during ordering for a specified parameter, or configured on the serial line using the ALARM command. When ordering a limit alarm, the alarm levels are set as follows: - For current output, an active alarm is indicated by the current being at the maximum of the scale (20 mA). - For voltage output, an active alarm is indicated by the voltage being at the maximum of the selected scale. For example, if the voltage output scale is 0 … 5 V, an output of 5 V indicates the alarm is active. Using the ALARM command you can also set a hysteresis value to prevent the repeated triggering of the alarm when the measurement fluctuates around a limit value. ALARM The following example shows that a high limit alarm has been enabled for channel 1. If the measured value rises above the -40.00 °C Td limit, analog channel 1 is set to 5 V (Limit Hi = -40.00, Level Hi = 5.00). The malfunction alarm (aerr) is disabled for both channels. >alarm ? Channel 1: Low Limit : OFF High Limit : ON Aerr : OFF Quantity : Tdf Limit Lo : 0.00 Limit Hi : -40.00 Hysteresis : 0.00 Level Lo : 0.00 Level Hi : 5.00 Channel 2: Low Limit : OFF High Limit : OFF Aerr : OFF Quantity : ppm Limit Lo : 0.00 Limit Hi : 0.00 Hysteresis : 0.00 Level Lo : 0.00 Level Hi : 0.00 >

VAISALA _______________________________________________________________________ 37 NOTE Avoid enabling more than one alarm type for a channel. Self-Diagnostic Alarm When the transmitter is performing a sensor purge or auto-calibration, the measurement output is frozen (unchanging) until the procedure is complete. The self-diagnostic alarm indicates this state by setting the analog output at a defined level, in the same way as the limit alarm (see page 36). Use the STATUS command to enable/disable the alarm, and to define the voltage/current levels (see example below). The channel is set to the value of Level Hi when purge or auto-calibration is active, and to Level Lo during normal operation. STATUS The following example shows the self-diagnostic alarm enabled for channel 1: >status Channel 1: Status : ON ? Level Lo : 0.00 ? Level Hi : 5.00 ? Channel 2: Status : OFF ? Level Lo : 0.00 ? Level Hi : 0.00 ? > Level Lo and Level Hi are shared between the STATUS and ALARM commands. For example, if you change the levels using the alarm command, it will also change when viewing the status command.

38 __________________________________________________________________ M210865EN-D Malfunction Alarm If the transmitter is malfunctioning, the channel output is set to a pre- defined level. This overrides the normal measurement output of the channel. You can specify the level using the AERR command: AERR Example: >aerr Ch1 error out : 20.000 mA ? Ch2 error out : 0.000 V ? > The current value is shown after the colon “:”. To set a new value, enter if after the question mark. The error output value must be within the valid range for the selected output mode. NOTE The error output value is displayed only when there are minor electrical faults such as a humidity sensor damage. When there is a severe device malfunction, the error output value is not necessarily shown. The malfunction alarm is always enabled for channels that are in the normal measurement modes (see section Configuring Analog Outputs on page 35), but you can enable or disable it using the ALARM command for channels that are in the ON/OFF output mode. Select Analog Output Quantity and Scaling Use the ASEL command to select the quantities output by the analog channels. Refer to Table 6 on page 41 for the selectable quantities. After entering the command, you will be prompted to enter the scaling of the quantities for both channels. Press enter to accept the suggested scaling values. ASEL [xxx yyy] where xxx = Analog channel 1 output quantity zzz = Analog channel 2 output quantity

VAISALA _______________________________________________________________________ 39 Example: >asel tdf ppm Ch1 Tdf lo : -80.00 'C ? Ch1 Tdf hi : 20.00 'C ? Ch2 ppm lo : 0.00 ppm ? Ch2 ppm hi : 1000000.00 ppm ? > Configuring Serial Line Operation Set Serial Line Settings Use the SERI command to set the serial line settings. The new settings will be taken into use when the transmitter is reset or powered up. Note that the transmitter will use its default serial line settings if it is in error state; see section Error State on page 58. Also note that changing the serial line settings will slightly alter how the transmitter works with the MI70 indicator. If you are not using the default settings of 19200 N 8 1, you will have to power off the MI70 before it can find the transmitter (i.e., you cannot connect it on-the- fly). SERI [b p d s] where B = baud rate (300, 600, 1200, 2400, 4800, 9600, or 19200) P = parity (n = none, e = even, o = odd) D = data bits (7 or 8) S = stop bits (1 or 2) Example: >seri 9600 e 7 1 Baud P D S : 9600 E 7 1 > Set Serial Line Response Time With the SDELAY command you can set delay (response time) of the serial line, or view the currently set delay value. Increasing the value by one increases the delay by 4 milliseconds. For example, value of 5 equals ~20 ms answer delay.

40 __________________________________________________________________ M210865EN-D SDELAY [x] Where x = Serial line delay (0 … 255) Example: >sdelay 1 Serial delay : 1 > Set Transmitter Address To operate in the POLL mode, the transmitter must have an address. If multiple transmitters share the same serial line, each transmitter must have a different address. For a description of the serial interface modes, see section Set Serial Interface Mode on page 42. ADDR [nn] where nn = address (0 ... 99) Example: >addr 1 Address : 1 > Format the Measurement Output Use the serial line command FORM to change the format or select the quantities for the output commands SEND and R. You can return to the default format using the ‘FORM /’ command. FORM [x] where x = Formatter string Formatter string consists of quantities and modifiers. The maximum length of the form string is 74 characters. When entering the command, use the abbreviations of the quantities. The quantities are presented in Table 6, and modifiers in Table 7.

VAISALA _______________________________________________________________________ 41 Table 6 FORM Command Quantities Quantity Description TDF Dewpoint/frost point temperature PPM Water content in parts per million PPB Water content in parts per billion PPMW Water content in parts per million by weight Note: For accurate ppm, ppb or ppmw reading, you must compensate for the pressure and molar mass of the process gas. Table 7 FORM Command Modifiers Modifier Description x.y Length modifier (number of digits and decimal places) #t Tabulator #r Carriage-return #n Line feed “" String constant #xxx ASCII code value (decimal) of a special character; for example, #027 for ESC ADDR Transmitter address with two characters [00...99] ERR Currently active transmitter errors in a five bit field: bit0bit1bit2bit3bit4 bit0 T MEAS error bit1 F meas error bit2 Voltage too low error bit3 Voltage too low for mA output error bit4 Ambient temperature error STAT Transmitter status in 4 characters. The status codes are the same as for the STAT command; see section Show Transmitter Status on page 34. SN Transmitter serial number TIME Current time; see the description of the TIME command on page 50. Ux Shows the name of the measurement unit using “x” number of characters. For example, U3 shows the name of the measurement unit with three characters. Examples: >form 4.2 TDF #r #n OK > >form 3.1 “H2O= “ ppm “ “ U3 #r #n OK >

42 __________________________________________________________________ M210865EN-D Select Unit The DMT152 Transmitter outputs dewpoint temperature Td in either Celsius or Fahrenheit degrees depending on the unit selection. The unit selection also affects the unit (bara or psia) for the pressure compensation. UNIT [x] where x = Selects the unit type to output: m = metric units, e.g. celcius n = nonmetric units, e.g. fahrenheit Set Serial Interface Mode SMODE [xxx] where xxx = STOP, RUN, or POLL In STOP mode: outputting only when command is issued, any command can be used. In RUN mode: outputting automatically, only command S can be used. In POLL mode: outputting only when command is issued, any command can be used after the line has been opened using the OPEN command. The polling mode can be used when more than one transmitter is connected to one serial bus. When set to POLL state, the transmitters communicate one at a time when the specific transmitter address is called on the serial line. See descriptions of the commands ADDR on page 40 and OPEN on page 49. Examples: >smode stop Output mode : STOP > >smode run Output mode : RUN > >smode poll Output mode : POLL >

VAISALA _______________________________________________________________________ 43 Configuring Measurement Parameters Enable or Disable Sensor Purge You can temporarily disable the sensor purge function using the XPUR command. Note that disabling the sensor purge will affect the measurement performance of the transmitter. XPUR [ON/OFF] Example: >xpur off Purge : OFF > After giving the XPUR OFF command, the transmitter will not perform sensor purge until one of the following events takes place: - Transmitter is reset or powered up - Sensor purge is enabled using the XPUR ON command Set Pressure Value for ppm Calculation The DRYCAP® 180U sensor in the DMT152 is not pressure dependent. When measuring dewpoint, pressure compensation is not needed. However, in the calculation of ppm volume concentration, the pressure of the system must be known. If you did not specify pressure compensation when ordering the product, use the commands below to enable the pressure compensation and set the pressure value. PRES [pp.pppp] XPRES [pp.pppp] where pp.pppp = Absolute pressure in the measuring point. The unit is bara if metric units have been selected, and psia if non-metric units are used.

44 __________________________________________________________________ M210865EN-D Command XPRES should be used if the value is changed frequently. The value set using the XPRES command overrides the PRES value, but it is not retained at reset. When the XPRES is set to 0, the last value set with PRES is used instead. Example: >pres 1.01325 Pressure : 1.01325 bar > The pressure conversion coefficients from other pressure units to bars is given in the table below. Table 8 Pressure Conversion Coefficients From To bara PaN/m² 0.00001 mmHg torr 0.001333224 inHg 0.03386388 mmH2O 0.00009806650 inH2O 0.002490889 atm 1.01325 at 0.980665 psia 0.06894757 Example: 29.9213 inHg = 29.9213 × 0.03386388 = 1.01325 bara NOTE Conversions from mmHg and inHg are defined at 0 °C and from mmH2O and inH2O at 4 °C. NOTE You can also set the pressure compensation value when you connect the DMT152 to the MI70 indicator. When using the MI70, the pressure unit is bara.

VAISALA _______________________________________________________________________ 45 Set Molar Mass for ppmw Calculation Use the MOL command to view and set the molar mass of the gas in the measurement environment. The molar mass parameter is used in calculating H2O ppmw. Some typical molar masses are: - Air 28.96 g/mol - N2 28.0134 g/mol - O2 32.00 g/mol - SF6 146.06 g/mol MOL [n] where n = Molar mass (in g/mol) of the gas in the measurement environment Examples: >mol 146.06 Mol : 146.0600 > >mol Mol : 146.0600 ? > NOTE You can also set the molar mass when you connect the DMT152 to the MI70 indicator. Serial Line Output Commands Start Measurement Output Use the R command to start the continuous outputting of measurement values as an ASCII text string to the serial line. The format of the measurement message is set with the FORM command. R

46 __________________________________________________________________ M210865EN-D Example (measurement message in default format): >r Tdf= -2.5 'C H2O= 4919 ppm Tdf= -2.5 'C H2O= 4918 ppm Tdf= -2.5 'C H2O= 4917 ppm … Outputting the results continues in intervals issued with the command INTV. You can stop the output by pressing the esc key, or with the command S. Since the interface is half-duplex, you must enter the commands when the transmitter is not outputting. Stop Measurement Output You can stop the measurement output by pressing ESC, or with the S command: S Set Output Interval INTV [n xxx] where n = time interval = 0 ... 255 xxx = time unit = "S", "MIN", or "H" Example: >intv 1 min Output interval: 1 MIN > The shortest output interval (with n = 0) is approximately one second due to the internal measurement cycle.

VAISALA _______________________________________________________________________ 47 Output a Reading Once SEND [aa] where aa = Transmitter address (0 ... 99). Must be specified if the transmitter is in POLL mode, and a line has not been opened using the OPEN command. Example: >send Tdf= -2.0 'C H2O= 5152 ppm > Troubleshooting and Maintenance Commands Display the Currently Active Errors Use the ERRS command to display the currently active transmitter error codes. Possible errors and their causes are listed in Table 9 on page 59. ERRS Example: >errs Voltage too low error > Test Analog Outputs The operation of the analog outputs can be tested with the ATEST command by forcing the output to a given value which can then be measured with calibrated multimeter. The command uses the currently selected analog output types for the channels (voltage or current) so you do not have to specify the unit. Before testing, you can verify the currently set analog output modes using the AMODE command. After testing the output, give the ATEST command again to exit the test mode.

48 __________________________________________________________________ M210865EN-D ATEST [xxx yyy] Where xxx = Channel 1 output value (V or mA) yyy = Channel 2 output value (V or mA) The output shows the test values of the analog channels, and diagnostic information that may be useful to Vaisala Service if there is a problem with the analog outputs. Example: >atest 1 15 1.00 2660 15.00 19425 > >atest 0.00 79 0.00 20110 > Calibrate Analog Output Use the ACAL command to force the analog outputs to the following values: - Current output: 2 mA and 18 mA - Voltage output: 10 % and 90 % of the range After entering the ACAL command, use a calibrated current/voltage meter to measure the output, and enter the values. Note that the calibration is only valid for the currently selected analog output modes. ACAL [channel] where Channel = Analog output channel: 1 or 2 Example: >acal 1 Ch1: I1 ( mA ) ? 0.166 I2 ( mA ) ? 18.1 3.61058569E+02 1.40927863E+03

VAISALA _______________________________________________________________________ 49 Extend Analog Output Range Use the AOVER command to allow the analog output channels to exceed their specified range by 10%. The scaling of the quantity remains as before; the extra range is used for additional measurement range in the wet end. AOVER [ON/OFF] The following example illustrates how the analog output is affected. Channel 1 outputs Td with voltage output 0 … 5 V (-80 °C … -30 °C). After giving the AOVER ON command, the range is 0 … 5.5 V (-80 °C … -25 °C). Note that the -30 °C Td point is still at 5 V. Example: >aover on : ON > Other commands Opening the Transmitter in POLL Mode Use the OPEN command to connect to a transmitter that is in POLL mode. OPEN [aa] where aa = address (0 ... 99) Resulting (only in POLL-state): >open 1 DMT152 1 line opened for operator commands >

50 __________________________________________________________________ M210865EN-D Closing the Connection to a Transmitter in POLL Mode The CLOSE command closes the connection to a transmitter. CLOSE Example: >close line closed > Display Command List HELP Set Time Use the TIME command to view and set the transmitter clock. The clock does not have a battery backup – it is reset to 00:00:00 when the transmitter is powered up or reset. TIME [hh mm ss] where hh = Hours (24-hour clock) mm = Minutes ss = Seconds Example: >time 12 30 00 12:30:00 > >time 12:30:05 >

VAISALA _______________________________________________________________________ 51 Reset Transmitter When the RESET command is given, the transmitter will restart as if it had just been powered on. All transmitter settings are retained. The serial line mode of the transmitter will be set to the mode that was set using the SMODE command. As the transmitter starts up, it performs the startup sensor purge and auto-calibration before resuming measurement. RESET Restore Factory Settings Use the FRESTORE command to restore the factory settings to the transmitter. All user settings will be lost. FRESTORE

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VAISALA _______________________________________________________________________ 53 CHAPTER 6 MAINTENANCE This chapter provides information on the maintenance of Dewpoint Transmitter DMT152. Cleaning the Transmitter The body of the transmitter can be cleaned by wiping with a moistened lint-free cloth. Do not immerse the transmitter in liquid, and do not use cleaning agents or solvents. Do not attempt to clean the filter or the sensor element. If the filter is contaminated, replace it with a new one. Changing the Filter If the filter is contaminated, it should be replaced. New filters can be ordered from Vaisala, with the order code 220957. Be careful when changing the filter, since it is easy to break the sensor when the filter is removed. CAUTION If the transmitter is installed in a pressurized chamber, always make sure that the pressure of the chamber is equalized with the ambient pressure prior to removing the transmitter. When the transmitter is removed for maintenance, cap the hole with a capped nut. This way, the process can be running although the transmitter is not in place. Plugs are available from Vaisala for ISO threaded connections (Vaisala order code 218773) and NPT threaded connections (Vaisala order code 222507).

54 __________________________________________________________________ M210865EN-D When replacing the filter, note the following: - The pores of the steel mesh may become blocked if touched. Do not touch the filtering surface with your hands or any tools. Always handle the filter from the top of the filter body. - Touching the filter with your fingers will also deposit oil and dirt on the filter, which may affect the measurement. Always handle the filter with gloved hands. - When installing the transmitter after a filter change, always use a new sealing ring (ISO and UNF threads only). 0711-195 Figure 17 Filter Structure where 1 = Vaisala DRYCAP® sensor 2 = Spring washer 3 = Stainless steel mesh filter (do not touch) 4 = Top of the filter Replace the filter as follows: 1. Grip the old filter from the top of the filter body using an 11 mm socket wrench. Turn the filter counterclockwise until it is loose. 2. Pull the filter straight out carefully; do not damage the sensor, and do not lose the spring washer. 3. Take the new filter, and insert it to the filter threads. The spring washer should be under the filter. 4. Tighten the new filter by turning it clockwise with the 11 mm socket wrench. Tighten to 5 N m.

VAISALA _______________________________________________________________________ 55 Calibration and Adjustment The DMT152 is fully calibrated as shipped from factory. The recommended calibration interval is 2 years. If the transmitter is used in the wet end of the measurement range, calibration should be done every year. Calibration should also be done if there is a reason to believe that device is not within the accuracy specifications. You can perform a simple field checking operation by comparing the readings of the DMT152 and the DM70 hand-held dewpoint meter with a calibrated reference probe. For more information, see section Field Check using DM70 on page 55. If there is need for calibration or adjustment, contact a Vaisala Service Center or your local Vaisala representative. See contact information on page 61. Field Check using DM70 To check of the accuracy of the DMT152 in the field, you need the following equipment: - A fully charged MI70 indicator (the measurement display that is included in the DM70 package) - A calibrated reference probe that is suitable for the intended measurement environment and dewpoint range. You can use a DMP74 probe from the DM70 for dewpoint down to -60 °C (-76 °F), or a second DMT152 for full measurement range. - Connection cable between DMT152 and the MI70 indicator (Vaisala order code 219980). - A reference environment with a stable dewpoint and temperature in a suitable range for both probes. The normal measurement environment of the transmitter can also be used, if it meets these criteria. NOTE In the procedure below, the readings of the probes are checked individually. You can also perform the field check so that you connect the reference probe simultaneously with the DMT152 you are checking. In this case, you need two of the connection cables if you are using a DMT152 also as the reference probe. Also, you must power one of the transmitters by other means than the MI70.

56 __________________________________________________________________ M210865EN-D Perform the check as follows: 1. Place the DMT152 in the reference environment (unless it is already). You can perform the check even if the DMT152 is currently being powered and used, as long as there is no cable connected to Port II. 2. Connect the MI70 connection cable between the MI70 indicator and Port II of the DMT152. 3. Turn on the MI70 indicator. If the analog channels of your DMT152 are configured to use the current output, and if the DMT152 is powered by the MI70, you will see an error message that indicates the supply voltage is too low for running the actual analog output. This is expected behavior; press OK to acknowledge the error and continue the field check. 0805-014 Figure 18 Supply Voltage Too Low for mA Output Error 4. Check and adjust the environment settings if prompted. You can change the pressure compensation value (only needed for ppm calculation), and the molar mass of the measurement gas. The pressure must be entered in bara; to enter the value in psia, use the serial line. For more information on these settings, see the following sections: - Set Pressure Value for ppm Calculation on page 43 - Set Molar Mass for ppmw Calculation on page 44 5. After a brief delay, the DMT152 should provide an approximate measurement reading of the selected quantities. Remember that it takes up to 15 minutes for the transmitter to start the active measurement.If the desired quantities are not shown on the display, select them from the Display – Quantities and units menu. 6. The Auto power off function should be disabled on the MI70 indicator to prevent the indicator from powering off in the middle of the check. While waiting for the active measurement to start, check the setting in the Settings - User Interface menu, and change if necessary.

VAISALA _______________________________________________________________________ 57 7. Write down the Td reading after the measurement has stabilized. 8. Turn off the MI70 indicator and disconnect the DMT152. 9. Insert the reference probe to the measurement environment, and connect it to the MI70 indicator. 10. Turn on the MI70 indicator. Check and adjust the environment settings if prompted. 11. Wait for the reference probe to provide a stable reading, and compare it with the reading from the DMT152. The difference between the readings will give you an indication of the approximate drift of the DMT152 and its need for calibration. As a general rule, the reading from the DMT152 should be within ±4 °C Td of the reading from the reference probe. NOTE Some notes on using the MI70 indicator with the DMT152: - If you disconnect the DMT152 while the MI70 indicator is on, the quantities measured will remain on the screen, but no measurement will be shown. - The messages from the transmitter (such as the supply voltage error) will appear in English even if the MI70 has been set to another language. Troubleshooting If you have a problem with the DMT152, first read the following sections concerning the behavior and error indications of the transmitter: - Configuring Analog Outputs on page 35 - Error Codes on page 59 - Error State on page 58 Possible causes of errors include insufficient operation voltage, physical damage to the transmitter, and incorrect connections. Connection problems can be caused by misconfiguration of the analog outputs or the serial line. Also remember that the start up of the transmitter may take up to 15 minutes. Some problems can be solved by simply resetting the transmitter. You can reset the transmitter by disconnecting the power or issuing the RESET command on the serial line.

58 __________________________________________________________________ M210865EN-D If you cannot locate the source of the error and return the transmitter to the normal state, please contact a Vaisala Service Center or your local Vaisala representative. See sections Error Codes on page 59 and Vaisala Service Centers on page 61 Error State If the voltage supplied to the DMT152 is too low for reliable operation, or there is some serious problem that prevents measurement, the DMT152 will enter an error state. The error state is indicated by the following: - Analog current output at 0 mA or 4 mA (according to selected range) - Analog voltage output at 0V - Serial line outputs asterisk characters (*** **) instead of measurement data The analog output levels for the error state are configurable using the AERR command; see section Malfunction Alarm on page 38. Note that the asterisk characters on the serial line may also appear during the start-up procedure. When the transmitter is in the error state, it will use the default serial interface settings, regardless of the currently set serial interface mode. If you have set a different mode with the SERI command, you will have to set your terminal program to the default settings of 19200 N 8 1 (also listed in Table 4 on page 30) before you can connect to the transmitter in error state.

VAISALA _______________________________________________________________________ 59 Error Codes The transmitter has error codes that can be displayed on the serial line using the ERRS command. See section Display the Currently Active Errors on page 47. NOTE All other errors except “Voltage too low for mA output error” will cause the DMT152 to enter the error state; see page 58. Table 9 Error codes Error Code Cause T meas error Internal error, can be caused by damage to the sensor. F meas error Internal error, can be caused by damage to the sensor. Voltage too low error Supplied operating voltage is too low for reliable operation. Voltage too low for mA output error Supplied operating voltage is too low for reliable operation of the analog current output. Note: It is normal to receive this error when using the MI70 indicator or the USB serial interface cable, as they do not provide a sufficient operating voltage to operate the current output. Ambient temperature error Ambient temperature out of operating range (probably too hot). Flash check sum error Internal error Param check sum error Internal error INFOA check sum error Internal error SCOEFS check sum error Internal error CURRENT check sum error Internal error

60 __________________________________________________________________ M210865EN-D Unknown Serial Settings If you are not sure what the serial settings of your transmitter are, follow the steps below to view and change them. 1. Make sure there are no other transmitters on the serial line. 2. Provide the transmitter with a 9 V supply voltage. This voltage is enough to start it in the error state. 3. Connect to the serial line using the error state serial line settings 19200 8 N 1. 4. Give the ? command to view the transmitter settings, including the serial settings and address. For an output example, see section Show Device Information on page 33. You may have to give the command several times if there are characters in the buffer. 5. If necessary, set new serial line settings using the SERI command. For instructions on using the command, see page 39. Technical Support For technical questions, contact the Vaisala technical support: E-mail [email protected] Fax +358 9 8949 2790

VAISALA _______________________________________________________________________ 61 Vaisala Service Centers Send the device to Vaisala Instruments Service Centre for calibration and adjustment, see contact information below. Remember to attach the yellow transport protection cap to the transmitter to protect it (and keep it dry) during transit. If the product needs repair, please contact Vaisala Instruments Service Center in your region before shipping the instrument. Follow the instructions given to you to speed up the process and to avoid extra costs.

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VAISALA _______________________________________________________________________ 63 CHAPTER 7 TECHNICAL DATA This chapter provides the technical data of Dewpoint Transmitter DMT152. Measured Variables Dewpoint temperature Measurement range -80 … -30 °C (-112 … -22 °F) Td Accuracy ± 2 °C (3.6 °F) Td Non-calibrated range -100 … +20 °C (-148 … +68 °F) Td Response time 63% [90%] at +20 °C (+68 °F) gas temperature and 1 bar pressure -80 -> -30 °C (-112 … -22 °F) Td 10 s [20 s] -30 -> -80 °C (-22 … -112 °F) Td 2 min [30 min] Analog output scalings option 1 -80 ... +20 °C (-112 ... +68 °F) Td option 2 -100 ... 0 °C (-148 ... +32 °F) Td option 3 free scaling ppm volume concentration Measurement range 0 … 500 ppm Accuracy at +20 °C (+68 °F), 1013 mbar ± (0.2 ppm + 20 % of reading) Operating Environment Temperature -40 … +60 °C (-40 … +140 °F) Relative humidity 0 … 100 %RH (up to +20 °C / +68 °F) Pressure 0 … 50 bar (725 psia) Measured gases non-corrosive gases Sample flow rate no effect on measurement accuracy

64 __________________________________________________________________ M210865EN-D Outputs Two analog outputs (scalable) 0 … 20 mA 4 … 20 mA 0 … 5 V 0 … 10 V Accuracy voltage output ± 0.01 V current output ± 0.01 mA Typical temperature dependence voltage output ± 0.001 % of span / °C current output ± 0.005 % of span / °C Digital output RS485 (2-wire half-duplex) ON/OFF output available instead of the 2nd analog output purge or auto-calibration inactive 0 V or 4 mA purge or auto-calibration active 5 V, 10 V or 20 mA OR exceeded Td or ppm limit user selectable General Sensor Vaisala DRYCAP® 180U Thin-film capacitive polymer sensor Startup time 10 .. 15 minutes Recommended calibration interval 2 years Operating voltage with RS485 output 11* … 28 VDC voltage output 15* … 28 VDC current output 21 … 28 VDC * For extended temperature down to -40 °C (-40 °F) or pressure up to 50 bar (725 psia) the supply voltage must be 21 ... 28 VDC. Supply current normal measurement 20 mA + load current during self-diagnostics max. 220 mA pulsed Load for voltage output min. 10 kOhm current output max. 500 Ohm Housing material AISI316L and PPS Stainless steel mesh filter AISI303, filter grade 18 μm Mechanical connections option 1 ISO G1/2” option 2 NPT 1/2" option 3 UNF 3/4"-16 Housing classification IP65 (NEMA 4) Storage temperature range -40 … +80 °C (-40 … +176 °F)

VAISALA _______________________________________________________________________ 65 Weight With ISO thread 190 g (6.70 oz) With NPT thread 210 g (7.41 oz) With UNF thread 186 g (6.56 oz) Complies with EMC standard EN61326-1, Electrical equipment for measurement, control and laboratory use - EMC requirements; Industrial environment. Output Cable Specifications Connector Straight, moulded M8 female (IEC 60947-5-2) Color Black Number of contacts 4 Conductors 0.25 mm² (× 4) / 0.00039 inch² (× 4) Insulation PVC Cable diameter 5.0 mm / 0.2 inch Protection class IP67 / NEMA 4 Wire color code EN50044 Spare Parts and Accessories Description Order Code Connection cable for DM70 219980 USB serial interface cable 219690 Sealing ring set ISO (copper, 3 pcs) 221524SP Sealing ring set UNF (copper, 3 pcs) 221563SP Stainless steel mesh filter (18 µm) 220957SP 110 … 240 VAC external power supply POWER-1 Plug Kit (ISO 1/2") 218773 Plug Kit (NPT 1/2") 222507 Analog/RS-485 output cables 2 m (6,5 ft) cable, M8 snap-on connector 211598 0.32 m (1 ft) shielded cable, M8 threaded connector HMP50Z032 3 m (9.8 ft) shielded cable, M8 threaded connector HMP50Z300 5 m (16.4 ft) shielded cable, M8 threaded connector HMP50Z500 10 m (32.8 ft) shielded cable, M8 threaded connector HMP50Z1000 Sampling cells (available only for ISO G1/2”) Sampling cell DMT242SC Sampling cell with 1/4" male Swagelok connectors DMT242SC2 Sampling cell with quick connector and leak screw DSC74 Two-pressure sampling cell DSC74B Separate cooling/venting coil for sampling cells DMCOIL

66 __________________________________________________________________ M210865EN-D Dimensions in mm (inches) 0710-133 Figure 19 DMT152 Dimensions