Mitsubishi Electric AE-200A Service Handbook page 22

[III System restrictions and notes]
The following shows an example of a wiring diagram for the M-NET transmission line of CITY MULTI.
The example in the figure below shows the cable length limit of centralized control M-NET transmission line and indoor-outdoor M-NET
transmission line for each system.
1. Farthest distance for M-NET transmission line (limited by attenuation of the signal waveform)
・
Make the distance between the transmission source and transmission destination of signals no more than 500 m (1640 ft).
If this maximum distance is exceeded, communication will become impossible due to the attenuation of the waveform.
a+c+d ≤ 500 m (1640 ft), a+c+e ≤ 500 m (1640 ft), a+b+f ≤ 500 m (1640 ft), c+d+b+f ≤ 500 m (1640 ft), c+e+b+f ≤ 500 m
(1640 ft)
2. Maximum power supply distance for M-NET transmission line (limited by voltage drop)
(1) Maximum total length of power feed for the centralized control transmission lines
・
Make the distance between the supply source and supply destination of power no more than 200 m (656 ft).
If this maximum distance is exceeded, communication will become impossible due to the voltage drop.
a+c+d ≤ 200 m (656 ft), a+c+e ≤ 200 m (656 ft), a+b+f ≤ 200 m (656 ft)
* If a system remote controller, etc. is connected to the transmission line for centralized control, a power supply unit
(PAC-SC51KUA) is required.
* There are cases where the supply source and supply destination of M-NET power differ depending on the setting of the
M-NET supply connector.
(2) Maximum total length of power feed for the indoor-outdoor transmission lines
・
Make the distance from an outdoor unit to the supply destination no more than 200 m (656 ft).
c+d ≤ 200 m (656 ft), c+e ≤ 200 m (656 ft)
*1 The wiring length of the M-NET remote controller must be 10 m (32 ft) or less. If 10 m (32 ft) is exceeded, the portion that
exceeds 10 m (32 ft) must be included in the calculations for the maximum total wiring length of the M-NET transmission line
(500 m (1640 ft)) and the maximum total power supply distance (200 m (656 ft)).
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