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Humidity Sensor Cable Applications:
Wire runs of 50 feet (mm) or less:
Use two separate shielded cables containing 20AWG
minimum, twisted pair conductors with overall shield.
Belden type 8762 or 88760 (plenum) or equivalent.
Connect both cable shield drain wires to the Unit
Controller as shown in figure 15.
Wire runs of 150 feet (mm) or less:
Use two separate shielded cables containing 18AWG
minimum, twisted pair conductors with overall shield.
Belden type 8760 or 88760 (plenum) or equivalent.
Connect both cable shield drain wires to the Unit
Controller as shown in figure 15.
Wire runs over 150 feet (mm):
Use a local, isolated 24VAC transformer such as Lennox
cat #18M13 (20VA minimum) to supply power to RH
sensor as shown in figure 16. Use two shielded cables
containing 20AWG minimum, twisted pair conductors
with overall shield. Belden type 8762 or 88760 (plenum)
or equivalent.
FIGURE 15
FIELD WIRING HOT GAS REHEAT UNITS (Using A
Humidity Sensor With Less Than 150 Ft. Wire Runs)
9
8
P298
J298A
1
2
B
3
4
C
5
6
7
D
10
A91
VIN
VO
GND
R
C
AI-1
HUM
TMP
DO-1
C
DI-1
DO-2
UNUSED
WIRE
NOT
CONNECTED
NOT
CONNECTED
DRAIN
A55 UNIT
CONTROLLER
FIGURE 16
FIELD WIRING HOT GAS REHEAT UNITS (Using A
Humidity Sensor With More than 150Ft. Wire Runs)
ISOLATED 24V
TRANSFORMER
9
8
P298
J298A
1
2
B
3
4
C
5
6
7
D
10
A91
VIN
VO
GND
R
C
AI-1
HUM
TMP
DO-1
C
DI-1
DO-2
NOT
CONNECTED
NOT
CONNECTED
DRAIN
A55 UNIT
CONTROLLER
FIGURE 17
FIELD WIRING HOT GAS REHEAT UNITS
(Using A Dehumidification Switch)
7
10
8
9
R
DI
−
4
C
Use 24 VAC (R) from any terminal
available on J299
−
2,
−
5, or
−
7.
J299
DEHUMIDIFICATION
SWITCH
