Haier MRV5-H - Page 261

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(3)Two-core nonpolar communication line with shield shall be adopted for communication lines between the valve
box and the indoor/outdoor unit. Three-core polar communication line with distinguished polarities and shield shall
be adopted for the wire controller connected to the indoor unit.
(4)All valve boxes within one system may share one overcurrent breaker for power supply. But it’s necessary to
compute total current capacity specication.
(5)For wring harness connected to the power terminal block, the terminal shall be pressed with a round (refer to the
following gure).
Wire
Insulating sleeve
Round. Press the terminal
1)The power terminal block shall not be crimped with 2 wires of di󰀨erent diameters.
Otherwise, poor crimp connection and looseness may lead to abnormal heating or
sparking of the line.
2)Refer to the following gure for crimping wires with the same diameter.
(6) Tighten terminal screws with proper screw driver. Screw driver of small dimension will damage the screw head
and fail to tighten properly.
(7) If terminal screws are tightened excessively, they may be damaged. Refer to the following table for tightening
torques of terminal screws:
Connect wires with the
same diameter on both
sides
It’s forbidden to connect
two wires on one side
Wires with di󰀨erent
diameters are not allowed
Dimension of terminal screw Tightening torque (N.m)
M3.5 (terminal block for communication line) 0.80~0.96
M4 (terminal block for power line) 1.18~1.44
M4 (terminal block for ground wire) 1.52~1.86
1)The maximum wiring length between the outdoor machine and the valve cage, the valve
cage and the indoor machine, and between valve cages is 1000 m at most. The total wiring
length is 2000m at most. The maximum branch number is 16.
2)The maximum wiring length between the valve cage and the wire controller for switching
working modes is 500 m at most.
(8)Power line is forbidden to the communication terminal block because it will damage the circuit control board.
(9)Wiring of communication lines shall be within the following scope. Exceeding the limit will possibly lead to
abnormal communication.