39
Relays — The fan relays are an integral component of the
control board. The fan motor speed control uses three SPDT
relays. The control relays are shown in Fig. 24. See the follow-
ing sections for a description of how the control relay is used
with each function.
FAN RELAY — The fan relay (K
1
) is factory-wired and
factory-installed on all units. The relay interfaces with the
Electronically Commutated Motor (ECM) motor control
circuit and automatically starts and stops the fan.
FAN SPEED RELAYS — The fan speed relays, K
2
and K
3
,
select the operating speed of the fan (High/Medium/Low). The
fan speed relays are factory-wired and factory-installed. These
relays control the speed of the motor.
Actuators
MODULATING OUTDOOR-AIR DAMPER ACTUATOR
(Fig. 28) — The outdoor-air damper actuator is factory-
supplied and factory-installed directly on the damper jackshaft.
All wiring between the actuator and the control is provided by
the factory. The actuator is mounted so that the spring return
will close the outdoor-air damper and open the return-air
damper on loss of power.
The actuator consists of an electronically controlled revers-
ible motor equipped with a microprocessor drive. The damper
actuator is supplied with approximately 8 ft of plenum rated
cable.
The actuator is capable of holding its position at any point in
the stroke and moving the damper in either direction.
The actuator is powered by the fused 24 vac transformer
located in the control box.
FACE AND BYPASS DAMPER ACTUATOR (Fig. 29) —
The actuator provides 35 in.-lb torque rating and is powered by
the 24-vac transformer located in the control box.
Face and bypass dampers are factory-supplied and factory-
installed on all face and bypass damper applications. These
actuators are proportional modulating, direct shaft mount type,
capable of being driven in either direction and holding position
at any point in the travel range.
The actuators are supplied with plenum rated cable.
Actuator connections depend on the application. Refer
to Application Data manual and wire label diagram for wiring
information.
The actuator is equipped with a SPDT damper end switch,
which senses when the damper is in the full bypass position.
The switch position is adjusted so that the switch closes
when the damper moves about 5 degrees from the full bypass
position.
FIELD-SUPPLIED TWO-POSITION RELIEF DAMP-
ER — A field-supplied relay is required to wire a field-
supplied two-position damper or ventilation unit, such as a heat
recovery ventilator (HRV) or energy recovery ventilator (ERV)
to the control module. A SPST normally open relay, such as
HB61KK324, must be field-installed and wired for use with
the field-supplied damper actuator or ventilation unit.
Using 18 AWG twisted cable, connect the relay coil con-
tacts to the control terminals J1-2 and T34. See Fig. 24 and 30.
To connect a field-supplied two-position damper actuator,
(Fig. 30), connect one contact of the actuator to the normally
open contact of the relay. Connect the common contact of the
relay to one leg of the power source. Connect the other contact
of the actuator to the outer leg of the power source.
1
2
3
1
2
3
1
2
3
1
2
3
RED
RED
RED
RED
RED
WHITE
WHITE
WHITE
WHITE
WHITE
BLACK
BLACK
BLACK
BLACK
BLACK
DRAIN WIRE
DRAIN WIRE
DRAIN WIRE
DRAIN WIRE
DRAIN WIRE
GROUND
UNIT VENTILATOR
1000 FT MAXIMUM
CCN
CONNECTOR
CCN
CONNECTOR
CCN
CONNECTOR
CCN
CONNECTOR
UNIT VENTILATOR UNIT VENTILATOR UNIT VENTILATOR
LEGEND
CCN — Carrier Comfort Network
Fig. 27 — CCN Communication Wiring
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