Eliwell EWPC 961/S Manual 

controller specifically designed for refrigeration applications. The instrument is equipped with a RS-485 port for the purpose of con- necting it into a Televis system. GENERAL DESCRIPTION The EWPC 961/S is a temperature con- troller specifically designed for refrigeration applications and provides time control for off-cycle defrost management. It incorpo- rates an output relay for compressor con- trol and a PTC sensor input. Furthermore, the instrument is equipped with a RS-485 port for the purpose of connecting it into a Televis system. A number of parameters are displayed alphanumerically to set up the in- strument for each specific application. The EWPC 961/S is supplied in the popu- lar “32x74” ELIWELL housing. OPERATION The EWPC 961/S is designed to operate strictly as a cooling control, which means that the switching differential is positive: the compressor cuts off at setpoint and is started at a temperature of set plus differ- ential. The on-board microprocessor pro- vides several timing functions for the defrost; the defrost cycle as well the de- frost cycle duration are user selectable. At the start of each defrost cycle, the com- pressor is simply stopped, regardless of the temperature control circuit. In addition, the EWPC 961/S offers several system protection features, all easy to un- derstand and easy to program This instru- ment is compatible with Televis software rel 2.4 or greater. In case its use with different software releases is required contact your supplier or Eliwell Customers’ Service. FRONT KEYPAD SET: push and release to display the set- point for 5 seconds. During this period the “SET” status light is on and the setpoint can be changed with the “UP” or “DOWN” button only. The system will automatically switch to normal display after 5 seconds upon release of buttons and the new value will be memorized. UP: used to increase the setpoint value, as well as the parameter when in program- ming. When held down for a few seconds, the change rate accelerates. DOWN: same functions, except to de- crease a value. DEFROST: push to initiate a manual de- frost cycle (override of programmed defrost start; programmed time resets to zero). Manual defrost can not be started while in setpoint or in parameter programming mode. This button must be activated for 5 sec- onds to start a defrost; the “DEF” status light will come on and the compressor is stopped. Led “COMP”: status light of the internal compressor relay. It is ON when the com- pressor is ON. Led “SET”: it is on during Setpoint display and programming; it blinks during parame- ter programming. Led “DEF”: status light of the defrost. It is on during automatic defrost; it blinks dur- ing manual defrost. PARAMETER PROGRAMMING Programming is easily accessed by holding the “SET” button down for more than 5 seconds; the first parameter is displayed while the status light “SET” remains blink- ing during the programming period. Other parameters are accessed with the “UP” and “DOWN” button. With the “SET” button, the actual setting of each parame- ter is displayed. To change a parameter setting, push the “SET” plus the “UP” (or “DOWN”). The system will automatically re- turn to its normal operating mode a few seconds after the programming procedure is completed or interrupted. DESCRIPTION OF PARAMETERS diF: diFferential. Switching differential (histeresis); it will al- ways be set with positive value (make on rise). HOW IT IS MADE • Dimensions: front 74x32 mm (2.913x1.260"), depth 67 mm (2.637") • Mounting: flush panel mount with mounting bracket • Protection: the instrument front- panel is waterproof IP65; an op- tional snap-on cover can be supplied to provide additional pro- tection of the rear terminal block • Connections: screw terminal block (2.5 mm2; one wire each terminal only, in compliance with VDE norms) • Display: 12.5 mm LED (0.50") • Output: one (1) SPDT relay 8(3)A 250VA • Input: PTC probe • Serial connection: RS-485 serial port for connection to the Televis system • Televis system compatibility: soft- ware release 2.0.4 or greater • Resolution: 1 °C (°F) • Accuracy: better than 0.5% of full scale • Power supply: 12…24 VA/C WHAT IT IS EWPC 961/S freezer control with Televis output

LSE: Lower SEt. This is the lower limit below which the user cannot change the setpoint. HSE: Higher SEt. Similar to “LSE”, however setting an upper limit for the setpoint. CAL: CALibration. Temperature read-out offset to allow for a fixed adjustment up or down due to probe location, if desired. cPP: compressor Probe Protection. Select compressor relay status in case of room probe defect. oF = compressor OFF in case of probe de- fect; on = compressor ON in case of probe de- fect. ctP: compressor type Protection. Select the type of (short-cycle) protection best suited for the compressor; the actual delay time is programmed with the next parameter. nP = no Protection; don = delay on start: delay applies when relay is energized; doF = delay at switching oFf. Delay after stop, i.e. time between stop and subse- quent start; dbi = delay between two successive starts. Limits the number of start-ups per hour. cdP: compressor delay Protection. The time delay - in minutes - applicable to the previous parameter “ctP”. dct: defrost count type. dF = digiFrost®: defrost starting time (“dit”) is calculated based on accumulative com- pressor running time; rt = real time: defrost initiation frequency is based on real time. Time between defrost starts is always the same; SC = Stop Compressor: a defrost cycle is activated each time the compressor stops; Fr = Free (the compressor relay has no re- lation with the defrost functions and con- tinues to regulate on Setpoint). dit: defrost interval time. Defrost initiation frequency in hours. dEt: defrost Endurance time-out. Defrost safety limit, expressed in minutes. Defrost cycle is terminated, regardless whether fully completed. ddL: defrost display Lock. Select whether or not to lock in the actual box temperature display during a defrost. n = no: during defrost the actual box tem- perature is displayed; y = yes: the temperature displayed at the start of a defrost is locked in and does not change during this cycle; Lb = Label: during the defrost the label “dEF” is displayed to indicate a defrost is in progress. NOTE: with the “y” and “Lb” selection, the display remains locked until the box tem- perature is pulled down again and reaches setpoint value. HAL: Higher ALarm. LAL: Lower ALarm. AFd: Alarm (Fan) differential. PAO: Power-on Alarm Override. dAo: defrost Alarm override. dPo: defrost (at) Power on. Selects whether the system should go through a defrost cycle at start-up (or after a power failure). n = no; y = yes. doh: defrost offset. Time delay of defrost start, expressed in minutes. dEA: dEvice Address. To select the (address) label of the device in relation to the supervisory system. FAA: FAmily Address. To select the (family) label of the device in relation to the supervisory system; further as “dEA”. tAb: tAble of parameters. This shows the configuration of the para- meters as set in the factory; can not be modified (for factory identification and di- agnostic purposes only). INSTALLATION The instrument is designed for flush panel mounting. Insert the unit through a 71x29 mm panel cut-out and affix with the U-bracket supplied. The ambient tempera- ture around the instrument should be kept between –5 and 65 °C (23…149 °F). CONNECTIONS EWPC 961/S 6 7 8 9 POWER SUPPLY 5 10 1 2 3 + – RS-485 compressor thermostat PTC probe DEFAULT SETTINGS - STANDARD MODELS Parameter diF LSE HSE CAL cPP ctP cdP dct dit dEt ddL HAL LAL AFd PAO dAo dPo doh dEA FAA tAb Description diFferential Lower SEt Higher SEt CALibration compressor Probe Protection compressor type Protection compressor delay Protection defrost count type defrost interval time defrost Endurance defrost display Lock Higher Alarm Lower Alarm Alarm (Fan) differential Power-on Alarm Override defrost Alarm override defrost (at) Power on defrost offset dEvice Address FAmily Address tAble of parameters Range 1…15 –99…HSE LSE…99 –20…20 oF / on nP / don / doF / dbi 0…15 dF / rt / SC 0…31 1…99 n / y / Lb 1…50 1…50 1…50 0…10 0…10 n / y 0…59 0…14 0…14 / Unit °C / °F °C / °F °C / °F °C / °F flag flag minutes flag hours minutes flag °C / °F °C / °F °C / °F hours hours flag minutes number number / Default 2 –55 40 0 oF nP 0 rt 6 30 y 50 50 1 10 10 n 0 0 0 /

Select a location which will not be subject to high humidity or condensation and allow some ventilation to provide cooling to the instrument. ELECTRICAL WIRING The instrument is equipped with an internal screw terminal block suitable for max 2.5 mm2 wiring (one wire each terminal only, in compliance with VDE norms). Make sure that the power supply corre- sponds with the rating shown on the in- strument, i.e. 12…24 Va/c. The 2-wire PTC type probe does not re- quire polarity and can easily be extended by using common 2-lead wire. It is strongly recommended to run the probe cable separate from line voltage wiring. Also, it is good practice to install the tip of the probe in upright position, to avoid moist from entering into the stainless steel sensor housing. The output relay contacts are voltage-free and are suitable for in-line switching of compressors up to 0.5 HP at 220 Va (or 0.25 HP to 110 Va). For larger loads, an external contactor must be used. ERROR ANNOUNCIATION The instrument is provided with only one error message “E1”, both in case of short- ed sensor and in case of sensor break, or sensor absence. The “E1” error message also appears in the event of underrange of the system tem- perature or in the event of overrange of the system temperature. TECHNICAL DATA Housing: black ABS plastic, self-estin- guishing. Dimensions: front 74x32 mm (2.913x1.260"), depth 67 mm (2.637"). Mounting: flush panel mount with mount- ing bracket. Protection: the instrument frontpanel is waterproof IP65; an optional snap-on cov- er can be supplied to provide additional protection of the rear terminal block. Connections: screw terminal block (2.5 mm2; one wire each terminal only, in compliance with VDE norms). Display: 12.5 mm LED (0.50"). Push buttons: located on front panel. Data storage: non-volatile EEPROM memory. Operating temperature: –5…65 °C (23…149 °F). Storage temperature: –30…75 °C (–22…167 °F). Output: one (1) SPDT relay 8(3)A 250Va. Input: PTC probe. Serial connection: RS-485 serial port for connection to the Televis system. Televis system compatibility: software rel 2.0.4 or greater. Resolution: 1 °C (°F). Accuracy: better than 0.5% of full scale. Power supply: 12…24 Va/c. DISCLAIMER This manual and its contents remain the sole property of Invensys Climate Controls s.p.a., and shall not be reproduced or dis- tributed without authorization. Although great care has been exercised in the preparation of this document, Invensys Climate Controls s.p.a., its employees or its vendors, cannot accept any liability whatsoever connected with its use. Invensys Climate Controls s.p.a. reserves the right to make any changes or improve- ments without prior notice. Invensys Climate Controls s.p.a. via dell'Industria, 15 Zona Industriale Paludi 32010 Pieve d'Alpago (BL) ITALY Telephone +39 0437 986111 Facsimile +39 0437 986066 Email [email protected] Internet http:/www.climate-eu.invensys.com 7/2000 ing cod. 9FT40072