2
Centralized
controller
L1
L2
L3
Power supply
unit
M-NET transmission line
(Centralized control line)
M-NET transmission line
(Indoor control line)
A transmission line
MA remote controller line
Maximum power feeding length for
the centralized control line:
L1
[
200 m (656 ft)
L2 + L3
[
200 m (656 ft)
Indoor unit
Indoor unit
Indoor unit
Indoor unit
ME
controller
MA
controller
M-NET
Outdoor
unit
Mr. SLIM
Outdoor
unit
M-NET
Adapter
Indoor unit
Bad example (Multiple ground of shielded wire)
(1) Ground wire connection
(2) Length of M-NET transmission line
Centralized
controller
Power supply
unit
Outdoor
unit (*1)
Outdoor
unit (*1)
M-NET transmit wire
NO
NO
NO
Centralized
controller
Power supply
unit
Outdoor
unit (*1)
Outdoor
unit (*1)
M-NET transmit wire
OK
Centralized
controller
Power supply
unit
Outdoor
unit (*1)
Outdoor
unit (*1)
M-NET transmit wire
OK (*2)
Good example (One spot ground of shielded wire)
Good example (One spot ground of shielded wire)
(*1) Refer to the appendix List of Models to check the applicable models.
Note: If the shield and earth are grounded in two or more locations, electrical circuit is generated through them, and a
potential difference is created because of the impedance difference between or among the ground locations.
This may cause noise in the shield. Ground at only one point, then no circuit is created and no noise gets in.
(*2) In case that the outdoor unit is grounded, connect the ground wire supplied as accessory to the S terminal (secondary)
of M-NET terminal block and M-NET ground terminal inside of electric box with using screws supplied.
(*2)
Attention for M-NET connection
Pay attention to the next points for wiring of shielded wires.
CAUTION
The shielded wires of M-NET transmission should be
connected with the ground wire at any only one place
of the unit to be connected.
• It can cause the transmission error due to noise.
Outdoor unit digital LED display reads "Ed" "A7" error.
Centralized controller reads “0403” “6607” error.
CAUTION
The shielded wires of M-NET transmission should be
used below the maximum line length.
• It can cause the transmission error.
Outdoor unit digital LED display reads "Ed" "A7" error.
Centralized controller reads "0403" "6607" error.
M-NET
terminal block
Ground wire
(accessory)
Transmit
wire
Shielded
wire
(3) Using dual set point
1. To activate dual set point, make sure that all units and controllers in one group have dual set point function.
2. To change the temperature display setting of existing group from single to dual set point, make sure to restart the
whole system related.
3. When ME remote controller is included in same group in the case of 2, make sure to initialize* ME remote controller
before use.
(*Refer to the ME remote controller installation manual. <Service Menu.>)
