Specifications

CommStat 4 Lead/Lag Controller Inputs (cont'd)
10. Lockout Relay (LOR)
 TheCommStat4hasalockoutrelayinput(LOR)andwillprovideaNormallyOpen(NO)orNormally
Closed(NC)outputinaccordancetothisinput.ThisfeatureisenabledintheConfigurationMode,screen
#10 by either selecting On(default)orOff. If On is selected, the control will turn the output off, energize
thelockoutrelayoutput(NOorNC),andannunciatewhichunitislockedoutontheLCDdisplay.Ifallthe
unitsarelockedout,themixedairrelaywillbeactivatedoneachunittoprovideemergencyventilation,
provided there is a call for cooling.
Cycling power will not reset the Lockout fault. A physical reset of the fault will be required by pressing the
Up and Down buttons for 4 seconds.
11. AUX1-IN/AUX2
TheCommStat4hastheoptionfortwo,drycontact,auxiliaryoutputsthatwillenergizebasedonthe
AUX1andAUX2inputs.EachAUXinputcanbeconfiguredtolookforanormallyopen(NO)ornormally
closed(NC)signalinConfigurationMode,screens#21and#22.Eachscreenwillallowtheuserthe
option of NO, NC, or OFFtodisablethefeature.Note:AUX1andAUX2arenotavailablewhenthe
Economizer configuration 2 is selected in screen 19.
 AUX1andAUX2areindependentfromtheoperationoftheboardandtheairconditionersor heat pumps.
CommStat 4 Lead/Lag Controller Outputs
(refer to the Thermostat and Line Voltage Connection Schematic on page 6)
1. Y or 1
 TheYor1outputenergizesthecompressorwhentheeconomizerisnotselected.Uponacallforcooling,
theY(1)andOterminalsareenergized.Onacallfor1ststageheating,theY(1)outputwillbeenergized.
There is a minimum compressor time off delay of 3 minutes for the lead unit and 4 minutes for the lag
unit. A minimum compressor run time is preset at three minutes by the controller.
2. G or 3
 TheGor3outputterminalenergizestheindoorfanduringeitherheatingorcooling.
3. W or 4
The W or 4 output terminal energizes the electric heat.
4. O (Heat Pumps) or Y2 (Air Conditioners with 2 Stage Compressors)
 TheOoutputterminalenergizesthereversingvalveonheatpumps.Thevalveisenergizedonacallfor
cooling.IfstagedairconditionersareselectedinConfigurationscreen#25,theOoutputbecomesthe
secondstagecoolingoutput,Y2.
5. Lockout Alarm
When enabled in screen #10 of the Configuration Menu, the CommStat 4 monitors the Lockout Relay
(LOR)inputforacontactclosure.IfthereisacontactclosurebetweentheLORterminals,thecontrol
willturnoffalloutputs,energizetheNOorNCcontacts,anddisplaywhichunitislockedoutontheLCD
display.Thedefaultsettingintheconfigurationis“On”.Ifalloftheconnectedunitsarelockedout,
theMixedAirRelay(MAR)willbeactivatedoneachoftheconnectedunitsandtheunitswillgointo
Emergency Ventilation mode. Cycling power will reset the Lockout Alarm.
6. Low (Control) Voltage Loss Alarm
The low voltage loss alarm relay provides a dry contact closure if control voltage is not present.
7. High (Line) Voltage Loss Alarm
The high voltage loss alarm relay will provide a dry contact closure if line voltage is not present.
8. Low Building Temperature Alarm
 TheLowBuildingTemperatureAlarmhasanadjustabletemperaturerangeof30°Fthru65°F(-1°Cthru
19°C) that may be adjusted in screen #8 of the configuration menu. If the temperature drops to this
setting, all outputs will be turned off and the LCD display will annunciate Low Building Temperature. There
isa2°F(1°C)differentialforthisalarmtoreset.
9. First Stage High Building Temperature Warning
 Thesetpointtemperatureisadjustablefrom70°Fthru140°F(21°Cthru60°C).Ifthissetpointis
reached, the control will display a First Stage High Building Temperature warning on the LCD display. The
defaultsettingforthisis85°F(29°C).Thereisa2°F(1°C)differentialforthisalarmtoreset.Thefirst
stagehightemperaturewarningsetpointisadjustableinscreen#6oftheConfigurationMenu.
10. Second Stage High Building Temperature Alarm
 Thissetpointisadjustablefrom75°Fthru145°F(24°Cthru63°C).Ifthissetpointisreached,alloutputs
areturnedoffwiththeexceptionoftheMixedAirRelay(MAR)andAirMoverRelay(AMR),andthecontrol
willdisplayaSecondStageHighBuildingTemperaturealarmontheLCDdisplay.Theeconomizers(ifair
conditioners or heat pumps with economizers are installed) will run in the emergency mode and the indoor
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