Bard MC4000 CONTROLLER CONNECTIONS, Specifications/Features For Alarm Boards, Sensors are

BASIC MC4000 CONTROLLER INPUT/OUTPUT SPECIFICATIONS

MC4000 CONTROLLER CONNECTIONS

Located on Main Controller Board

Unit #1	C – 24VAC common
	R – 24VAC hot
	G – fan (Form A, NO)
	Y1 – 1st-stage cool (Form A, NO)
	Y2 – 2nd-stage cool (Form A, NO)
	W – heat (Form A, NO)
Unit #2	C – 24VAC common
	R – 24VAC hot
	G – fan (Form A, NO)
	Y1 – 1st-stage cool (Form A, NO)
	Y2 – 2nd-stage cool (Form A, NO)
	W – heat (Form A, NO)
F1-F2	Fire/smoke interface
	Shipped with jumper installed (a)
48Vdc	Back-up power input
	-24Vdc or –48Vdc
	-20V to –56V range
		NOTE:
Local	Main sensor, 12-inch leads
	CU – copper, AG – silver	Sensors are
	Polarity sensitive	solid state,
Rem 1	Optional remote indoor sensor	not RTD.
	CU – copper, AG – silver
		Use Bard
	Polarity sensitive
Rem 2	Optional remote indoor sensor	sensors only.
	CU – copper, AG – silver
	Polarity sensitive
Gen	Generator interface G1-G2
	Shipped with jumper installed (a)
H1-H2	Humidity controller input
	Requires optional controller
	Field installed

(a)These connections require either jumper or Normally Closed (NC) relay contact at the Fire/Smoke and Generator interface for Controller to function.

Note: All alarm and output relays are dry contacts rated 1A @ 24 VAC.

Note: All alarm relay outputs have 10-second delay before issuing to protect against nuisance alarm signals.

SPECIFICATIONS/FEATURES FOR ALARM BOARDS

MC4000-A w/Optional Base Alarm Board (Inputs/Outputs)

NOTE: If this alarm board was not originally factory installed, it can be field-installed at anytime. Bard part number is AB3000-A.

Inputs
Lockout 1	2,3 – input from HVAC #1
Lockout 2	2, 3 – input from HVAC #2
Outputs
Smoke/Fire	Form C (SPDT)
Lockout 1	Form C (SPDT)
	Refrigerant alarm HVAC #1
Lockout 2	Form C (SPDT)
	Refrigerant alarm HVAC #2
Power Loss 1	Form C (SPDT)
	Power loss HVAC #1
Power Loss 2	Form C (SPDT)
	Power loss HVAC #2
Low Temp	Form C (SPDT)
	Low temperature alarm
High Temp 1	Form C (SPDT)
	High temperature alarm #1

MC4000-B w/Enhanced Version Alarm Board (Additional Outputs) plus MC4000-A Inputs/Outputs

NOTE: If this alarm board was not originally factory installed, it can be field-installed at anytime. Bard part number is AB3000-B.

High Temp 2	Form C (SPDT)
	High temperature alarm #2
Controller	Form C (SPDT)
	Controller failure alarm
Econ 1	E, F - Form A (NO)
	See note (b)
Econ 2	E, F - Form A (NO)
	See note (b)
2nd Stage (c)	Form C (SPDT)
	2nd-stage cooling alarm

(b)Make these connections to terminals E & F in HVAC 1 and 2 respectively if desired to have economizers open for emergency ventilation at High Temp Alarm #2 setpoint condition.

(c)For units with 2-stage compressors, 2nd stage cooling alarm activates on cooling Stage 3 initiation.

Alarm relays can be wired for NO (close on alarm) or NC (open on alarm) strategy. Alarm relays can be used individually if there are enough available building alarm points, or can be arranged into smaller groups or even a single group so that all alarm capabilities can be utilized. When multiple alarms are grouped together and issued as a single alarm there will be no off-site indication of which specific problem may have occurred, only that one of the alarms in the group has been triggered. The individual alarm problem will be displayed on the LED display on face of the controller.

Manual	2100-563C
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