Mitsubishi Electric PUZ-HA30NHA5 Service Manual page 14

8-3. INDOOR – OUTDOOR CONNECTING CABLE
Outdoor power supply
Indoor unit-Outdoor unit
Note: The Maximum cable length may vary depending on the condition of installation, humidity or materials, etc.
Indoor/Outdoor separate
power supply
Indoor unit-Outdoor unit
Note: The optional indoor power supply terminal kit is necessary.
Be sure to connect the indoor-outdoor connecting cables directly to the units (no intermediate connections).
Intermediate connections can lead to communication errors if water enters the cables and causes insufficient
insulation to ground or a poor electrical contact at the intermediate connection point.
8-4. M-NET WIRING METHOD
Points to notice:
(1) Outside the unit, transmission wires should stay away from electric wires in order to prevent electromagnetic noise from making
an influence on the signal communication. Place them at intervals of more than 5cm. Do not put them in the same conduit tube.
(2) Terminal block (TB7) for transmission wires should never be connected to 208/230 V power supply. If it is connected,
electronic parts on M-NET P.C. board may be burnt out.
(3) Use 2-core x AWG16 [1.25 mm
sent or received normally if different types of transmission wires are put together in the same multi-conductor cable. Never
do this because this may cause a malfunction.
Centralized
controller
Power
supply unit
It is acceptable if M-NET wire (non-polar, 2-cores) is arranged in addition to the wiring for A-control.
(4) Ground only one of any appliances through M-NET transmission wire (shield wire). Communication error may occur due to
the influence of electromagnetic noise.
"Ed" error will appear on the LED display of outdoor unit.
"0403" error will appear on the central-control remote controller.
If there are more than 2 grounding spots on the shield wire, noise may enter into the shield wire because the ground wire and shield
wire form one circuit and the electric potential difference occurs due to the impedance difference among grounding spots. In case of
single spot grounding, noise does not enter into the shield wire because the ground wire and shield wire do not form 1 circuit.
To avoid communication errors caused by noise, make sure to observe the single spot grounding method described in the
installation manual.
OCH607
Max. 164 ft [50 m]
Max. 147 ft [45 m]
3 o AWG13(polar)
3 o AWG15(polar)
] shield wire (CVVS, CPEVS) for the transmission wire. Transmission signals may not be
2
Refrigerant
address 00
M-NET
address 01
A-control
remote
controller
O Bad example (Multi spot grounding of shield wire)
Centralized Power
M-NET type
controller supply unit
outdoor unit
M-NET transmission wire
Good example 1 (Single spot grounding of shield wire)
Power
Centralized M-NET type
supply unit
controller outdoor unit
M-NET transmission wire
Good example 2 (Single spot grounding of shield wire)
Power
Centralized M-NET type
supply unit
controller outdoor unit
M-NET transmission wire
Wire No. o Size
3 o AWG13(polar) and S3 separated
Wire No. o Size
Max. 393 ft [120 m]
2 o Min. AWG22
Refrigerant
address 00
M-NET
address 02
A-control
A-control
remote
remote
controller
controller
M-NET type M-NET type
outdoor unit outdoor unit
M-NET type M-NET type
outdoor unit outdoor unit
M-NET type M-NET type
outdoor unit outdoor unit
14
Max. 262 ft [80 m]
Refrigerant
address 00
M-NET
address 03