DetailedOperation9
059840‐00Rev.AHeat‐TimerCorp.
RemoteShutdown/TSTATEnable
Theremoteshutdown/TSTATenablefeaturesetsthesignal(openorshort)ontheEPU‐DShutdownterminals
(17and18)thatallowsthecontroltooperate.
• ForShutdown,an“open”signalallowsthecontroltooperateandprovideheat.Whenshorted,thecontrol
isdisabled.
• ForTSTATEnable,a“short”signalallowsthecontroltooperateandprovideheat.Whenopen,thecontrol
isdisabled.
Whenthecontrolisdisabled,theBurnerandMotorizedValveoutputrelaysarede‐energized,turningoffthe
boilerorclosingthemotorizedvalve.
ThisfeaturecanbeusedwhenitisdesirabletodeactivatetheEPU‐Dfromaremotelocationorwithanother
controller,suchasaBuildingManagementSystem(BMS).
EPU‐DOutputs
ValveActuator
TheEPU‐Disdesignedtoconnecttoamotorizedvalveactuator.Usingtheinputsfromtheoutdoortemperature
sensorandthesystemtemperaturesensor,theEPU‐Dcontrolstheheatingsystembyopeningandclosingthe
motorizedvalveactuator.
BoilerBurner
TheEPU‐Disdesignedtoconnecttotheboilerburner.Usingtheinputsfromtheoutdoortemperaturesensor
andthesystemtemperaturesensor,theEPU‐Dcontrolstheheatingsystembyturningtheboilerburneronor
off.
CAUTION
TheShutdownsignalmustbedry‐contactonly.DONOTplacevoltage
acrosstheShutdownterminals.