Carrier 50HCQA Filter Status Switch, Supply Fan Status Switch, Space Relative Humidity Sensor

50HCQA

On 50HCQ units equipped with factory-installed Smoke Detector(s), the smoke detector controller implements the unit shutdown through its NC contact set connected to the unit’s CTB input. The FSD function is initiated via the smoke detector’s Alarm NO contact set. The PremierLink communicates the smoke detector’s tripped status to the CCN building control. See Fig. 30, the PremierLink wiring schematic.

Filter Status Switch —

This function is available only when PremierLink is configured for (Space) Sensor Mode.

PremierLink control can monitor return filter status in two ways: By monitoring a field-supplied/installed filter pressure switch or via supply fan runtime hours.

Using switch input: Install the dirty filter pressure switch according to switch manufacturer’s instructions, to measure pressure drop across the unit’s return filters. Connect one side of the switch’s NO contact set to CTB’s THERMOSTAT-R terminal. Connect the other side of the NO contact set to TB1-10. Setpoint for Dirty Filter is set at the switch. See Fig. 42.

Filter Switch (NO, close on rising pressure (high drop))

CTB

Thermostat

R

TB1PL

10 J4-4

C08216

Fig. 42 - PremierLink Filter Switch Connection

When the filter switch’s NO contact set closes as filter pressure drop increases (indicating dirt-laden filters), the input signal to PremierLink causes the filter status point to read “DIRTY”.

Using Filter Timer Hours: Refer to Form 33CS-58SI for instructions on using the PremierLink Configuration screens and on unit alarm sequence.

Supply Fan Status Switch —

The PremierLink control can monitor supply fan operation through a field-supplied/installed differential pressure switch. This sequence will prevent (or interrupt) operation of unit cooling, heating and economizer functions until the pressure switch contacts are closed indicating proper supply fan operation.

Install the differential pressure switch in the supply fan section according to switch manufacturer’s instructions. Arrange the switch contact to be open on no flow and to close as pressure rises indicating fan operation.

Connect one side of the switch’s NO contact set to CTB’s THERMOSTAT-R terminal. Connect the other side of the NO contact set to TB1-8. Setpoint for Supply Fan Status is set at the switch. See Fig. 43.

Fan (Pressure) Switch (NO, close on rise in pressure)

CTB

Thermostat

R

TB1PL

8 J4-6

C08118

Fig. 43 - PremierLink Wiring Fan Pressure Switch

Connection

Remote Occupied Switch —

The PremierLink control permits a remote timeclock to override the control’s on-board occupancy schedule and place the unit into Occupied mode. This function may also provide a “Door Switch” time delay function that will terminate cooling and heating functions after a 2-20 minute delay.

Connect one side of the NO contact set on the timeclock to CTB’s THERMOSTAT-R terminal. Connect the other side of the timeclock contact to the unit’s TB1-2 terminal.

Remote Occupied	CTB
	Thermostat
	R
Time Clock	TB1	PL
	2	J4-12

C08214

Fig. 44 - PremierLink Wiring Remote Occupied

Refer to Form 33CS-58SI for additional information on configuring the PremierLink control for Door Switch timer function.

Space Relative Humidity Sensor —

The RH sensor is not used with 50HCQ models at this time.

Power Exhaust (output) —

Connect the accessory Power Exhaust contactor coils(s) per Fig. 45.

Power Exhaust			TB1	PL
	PEC	TAN	15	J8-3
			CTB
			THERMOSTAT
		GRA	C

C08120

Fig. 45 - PremierLink Power Exhaust Output

Connection

CCN Communication Bus —

The PremierLink controller connects to the bus in a daisy chain arrangement. Negative pins on each component must be connected to respective negative pins, and likewise, positive pins on each component must be connected to respective positive pins. The controller

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