MR4 Refrigeration Temperature/Defrost Control …

1 FANs 125, 121 Temperature Controls SectionAInstallation BulletinIssue Date 1199 1999 Johnson Controls, No. 24-7664-1687, Rev. No. LIT-125193 IMPORTANT:All MR4 controls are designed foruse only as operating an operating controlfailure would result in personalinjury or loss of property, it is theresponsibility of the installer toadd devices (safety, limitcontrols) or systems (alarm,supervisory systems) that protectagainst, or warn of, to the MR Series Refrigeration TemperatureControls Product Bulletin, LIT-125199, for necessaryinformation on operation and performancespecifications for this MR4 Control is not position-sensitive but should bemounted for convenient wiring and mount the Panel Mount version, ensure that thereis at least 2 3/4 inches (70 mm) space behind thepanel.

2 Make a cutout 1 3/16 x 2 13/16 inches(29 x 71 mm). Remove retaining clip from the the Control into the hole. Install retaining clip andadjust for mount the DIN Rail Mount version, install the DINrail where appropriate. Snap the Control onto the railinto and ReplacementField repair of the Control should not be made. In caseof a defective or improperly functioning Control , checkwith your nearest authorized Johnson Controls/PENN distributor. When contacting the supplier forreplacement, state the model number of the number can be found on the data !

3 WARNING:Shock Hazard. To avoidpossible electrical shock ordamage to equipment,disconnect power supply beforewiring any these wiring guidelines: All wiring must conform to the National ElectricCode and local regulations. Make all wiring connections using adequate gaugecopper conductors only. Connectors are rated for14-22 AWG to ControlV1 V2 PowerSupplyCompressorEvaporatorFanDefros tSCS2S1D CDProcess Temperature SensorBinary InputAlarmEvaporatorTemperatureSensorFrF nDfA1 A2C1C2C3 SensorCommonBinary CommonTe r mi n a l Not UsedRefer to Rating Table for more 1: MR4 DIN Rail Mount ControlCSCS1S2DV1 V2 Internal to ControlPowerSupplyEvaporator TemperatureSensorBinaryInputProcess Temperature SensorCommonCompressorAlarmDefrostEvapor atorFanFr A1 Df FnRefer to Rating Table for more 2.

4 MR4 Panel Mount ControlINSTALLATION BULLETINMR4 Refrigeration Temperature/Defrost Control2 A MR4 Refrigeration Temperature/Defrost Control installation BulletinUse Table 1 with function So to compensate for longsensor 1: Sensor Wire Size and Length18 AWG20 AWG22 AWGO ffset300-599 ft91-183 m190-374 ft58-114 m120 -239 ft36-73 m1F 1C 600-899 ft183-274 m375-564 ft114-172 m240-349 ft73-107 m2F 2C 900+ ft274+ m565+ ft172+ m350+ ft107+ m3F 3C Table 2: Rating TableRating Category120 VAC240 VAC24 VDCH orsepower1/41/2-Full Load Rotor (non-motor)Amperes888 Pilot Duty VA275450-Relay outputs must not exceed 20 amperes totalconnected load.

5 Power source is 24 VAC. Alarms requireseparate external power ComplianceThis equipment has been tested and found to complywith the limits for a Class A digital device pursuant toPart 15 of the FCC Rules. These limits are designed toprovide reasonable protection against harmfulinterference when the equipment is operated in acommercial environment. This equipment generates,uses, and can radiate radio frequency energy and, ifnot installed and used in accordance with theinstruction manual, may cause harmful interference toradio communications.

6 Operation of this equipment ina residential area is likely to cause harmfulinterference, in which case the user will be required tocorrect the interference at his/her own DOC ComplianceThis digital apparatus does not exceed the Class Alimits for radio noise emissions from digital apparatusset out in the Radio Interference Regulations of theCanadian Department of Up and Down buttons to scroll through processtemperature, binary input status (On or OF), andauxiliary temperature sensor reading (F2 if none). After15 seconds of inactivity, the display shows the the ControlTo lock and unlock the unit for programming:Press the Enter, Up, and Down buttonssimultaneously and hold until - - - isdisplayed.

7 Hold for about 10 seconds until thecurrent temperature is change the setpoint:1. Hold the Enter button for approximately3 seconds. The display will change toshow the setpoint. Release the Press the Up or Down button until youreach the new Press the Enter button to save the :If the Enter button is not pressed after selecting the newsetpoint, the new setpoint is not saved. The Control revertsto the original run the self-test procedure:IMPORTANT:Disconnect loads before self-testprocedure. Cycle power to resumenormal the Up and Down buttons in sequence,and hold for 5 begin a manual defrost cycle:Hold the Defrost button for 3 begin a deep freeze cycle:Press the Enter and Up buttons in sequenceand hold both for 5 seconds.

8 The compressorstatus LED will program values other than setpoint:1. Hold the Enter button for about 10seconds. The display changes to Press the Up or Down button until thedesired parameter is Press the Enter button. The parameter scurrent value is Press the Up or Down button until thedesired value is Press the Enter button to save the newvalue. After 10 seconds of inactivity, thedisplay will return to its normal :If the Enter button is not pressed after selecting the newvalue, the new value is not saved.

9 The Control reverts to theprevious MR4 Refrigeration Temperature/Defrost Control installation Bulletin 3 Table 3: Functions and SettingsFunctionDescriptionSetting RangeDefaultSI:SetpointPrimary temperature setpoint at which compressorcontrol contacts open on temperature fall-40 to 158 F (-40 to 70 C)---HY:Hysteresis (Differential)Temperature difference relative to setpoint at whichcompressor Control contacts close on temperature rise1 to 9 F (1 to 9 C )5LL:Low Setpoint StopHigh setpoint adjustment limit-40 F (-40 C) to HL-25HL:High Setpoint StopLow setpoint adjustment limitLL to 158 F (70 C)40CC:Anti-short Cycle DelayMinimum time between two compressor On cycles0 to 9 minutes1Co:Deep Freezing TimeTime compressor forced On during deep freeze0 to 99 minutes60AH:High Temperature AlarmTemperature above setpoint where alarm is initiated0 to 50 F (0 to 50 C )10AL:Low Temperature AlarmTemperature below setpoint where alarm is initiated-50 to 0 F (-50 to 0 C )-10Ad.

10 Alarm DifferentialTemperature difference between alarm On and Off1 to 9 F (1 to 9 C )5At:Alarm Time DelayDelay between alarm detection and activation0 to 99 minutes3dF:Defrost TypeSelect defrost type0 = electric heater1 = hot gas0dE:Defrost End ModeDefrost termination type; note that defrost cycle alwaysends after time set for dd0 = time1 = temperature1dt:Defrost TerminationTemperatureOnly used when dE = 1; defrost ends whentemperature reaches dt32 to 68 F (0 to 20 C)55di:Defrost IntervalTime between two subsequent defrost cycles; whendi=1 hour, dd cannot exceed 40 to 99 hours7dd:Maximum Defrost DurationDefrost ends after this time, even if defrost endtemperature has not been reached.