17
NOTE - Each communication wire from the MS box should follow the refrigerant piping for that port.
Tightening torque for the terminal screws
•
Use the correct screwdriver for fighting the terminal
screws. If the screwdriver blade is too small, the head
of the screw might be damaged, and the screw will
not be properly tightened.
•
If the terminal screws are over tightened, screws
might be damaged.
•
Refer to the table below for the tightening torque of
the terminal screws.
•
After wiring, confirm all connections are correct; Then
turn on power supply to the unit.
Table 3. Terminal Screw Tightening Torque
Tightening torque
(lb-ft)
Terminal base of
remote controller/Signal
transmission wire (X2M)
0.58-0.72
Terminal base of power
supply (X1M)
0.87-1.06
Grounding terminal (M4)
1.06-1.43
Figure 16. Typical Communication Wiring Diagram (VRF Heat Recovery System)
Install a terminating resistor at terminals P and Q for each individual unit
when connected directly to an MS Box port.
P Q
All shields of shielded cable connect to GROUND terminal,
not to terminal E
.
18 GA., stranded, 3-conductor, shielded control wire (polarity sensitive).
Typical Wiring Diagram, NEC/CEC and Local Codes apply.
Outdoor Unit
(Main Unit)
Outdoor Unit
(Sub1 Unit)
Outdoor Unit
(Sub2 Unit)
(H1H2E)
(H1H2E)
(H1H2E)
(PQE)
(PQE)
(PQE)
(PQE)
(PQE)
(PQE)
(PQE)
(PQE)
(PQE)
(PQE)
(PQE)
Ground cable shield
DO NOT connect to E
Mode
Selection
Box
Mode
Selection
Box
