GEN III
– VVT
Dampers
Install dampers into HVAC duct so damper actuators and control boards are easily accessed. Damper
may be mounted in an area where the ambient temperature is between 32 and 125 degrees Fahrenheit.
Round dampers should be mounted with damper actuators between 9 and 3 O’clock position.
Once GEN III controller and supply dampers are installed, install 24 VAC 40 VA transformer and wire
secondary 24 volts to the C R (IN - D) terminals on GEN III controller. Using 18 ga. thermostat wire, wire C
R (OUT - E) terminals and daisy chain power wires to the first damper. Continue daisy chain wiring from
first damper to second, third, etc., until all supply dampers are wired with power.
Note: Maintain R and C wiring polarity throughout the system to improve communications.
Once power wiring is daisy chained to all supply dampers in the system, use Belden 8740 twisted pair
communications wire to install communications loop. Install communications wire using the RX and TX
(G) terminals on GEN III controller and daisy chain to the first supply damper in the system and wire to RX
TX terminals of the communication damper board. Continue daisy chain to the next damper using RX TX
terminals of communication damper board to the RX TX of the next damper control board, repeating this
process until all supply dampers are wired into the communications loop. Communications wiring is
polarity specific, if RED communications wire is on RX at the GEN III controller, then RED wire is connected
to RX throughout the system.
GEN III CONTROLLER
POWER SWITCH
ID / SYNC
24VAC IN
24VAC OUT
TO UNIT TERMINALS
RS485 COMMUNICATION LINK ( BELDEN 8740)
AUX SENSOR (AS)
LEAVING AIR SENSOR (LVAIR)
OUTSIDE AIR SENSOR (OA)
RETURN AIR SENSOR (RA)
DAISY CHAIN 24VAC AND DATALINK CABLE (BELDEN 8740)
TO ALL COMMUNICATING DAMPER BOARDS
EXPANDABLE TO 20 ZONES
MODULATING DAMPER
DM-1
C
C
R
R
RX
RX
TX
TX
MC
RO
RC
C
AUX
MODULATING DAMPER
DM-3
C
C
R
R
RX
RX
TX
TX
MC
RO
RC
C
AUX
MODULATING DAMPER
DM-2
C
C
R
R
RX
RX
TX
TX
MC
RO
RC
C
AUX
MC
RC
RO
MC
RC
RO
MC
RC
RO
(D)
(E)
(G)
DAMPER INSTRUCTIONS
STATUS LIGHTS
12