65
Check method of M-NET transmission power board
Normal
24-30V DC ?
*Correct the short circuit point on
the M-NET transmission line.
24-30V DC ?
Is the incoming main voltage
208/230V ±10% AC ?
*Check wiring
*Replace M-NET transmission power board
*Check breaker and incoming power supply
*Check noise filter board
*Check wiring
Check the voltage between M1 and M2 on the
transmission terminal block TB3
Disconnect the indoor - outdoor transmission wiring
from the terminal block TB3 , and check the voltage
between M1 and M2 on TB3 again.
*To check the voltage of the parts on this board with a tester is difficult due to its location.
Test points are limited.
No
Yes
(24-30V DC )
No
Yes
(208-230V AC )
No
Yes
(24-30V DC )
M-NET transmission power board check
Noise filter
circuit board
1
-
3
CNAC1(WHT)
Multi controller board
M1 M2
CNS1
(RED)
2 1
CN102
(WHT)
TB3
4 3 2 1
208/230V
±10% AC
NI
LI
208/230V
±10% AC
CN1
CN2
24V-30V DC
24V-30V DC (Non-polar)
To Indoor Unit
M-NET transmission power board
L2
L1
TB1