Mitsubishi Electric PUHY-HP120TNU-A, Service Handbook

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[2-7 Example System with an MA Remote Controller ]
HWE18240_GB
chapter 2 -
17
2 Restrictions
(4) Wiring method
1) Indoor/outdoor transmission line
Same as 2-7-1
Œ
Only use shielded cables.
Shielded cable connection
Same as 2-7-1
2) Transmission line for centralized control
Daisy-chain terminals M1 and M2 on the terminal block
for transmission line for centralized control (TB7) on the
outdoor units (OC) in different refrigerant circuits and on
the OC, OS1, and OS2 (Note a) in the same refrigerant
circuit
If a power supply unit is not connected to the transmis-
sion line for centralized control, replace the power jump-
er connector on the control board from CN41 to CN40 on
only one of the outdoor units.
a) The outdoor units in the same refrigerant circuit are auto-
matically designated as OC, OS1, and OS2 in the order
of capacity from large to small (if two or more units have
the same capacity, in the order of address from small to
large).
b) When not daisy-chaining TB7's on the outdoor units in
the same refrigerant circuit, connect the transmission
line for centralized control to TB7 on the OC (Note a). To
maintain centralized control even during an OC failure or
a power failure, daisy-chain TB7 of OC, OS1, and OS2.
(If there is a problem with the outdoor unit whose power
jumper was moved from CN41 to CN40, centralized con-
trol is not possible, even if TB7's are daisy-chained).
c) When connecting TB7, only commence after checking
that the voltage is below 20 VDC.
Œ
Only use shielded cables.
Shielded cable connection
Daisy-chain the S terminal on the terminal block (TB7) on
the outdoor units (OC, OS1, OS2) with the shield wire of
the shielded cable. Short-circuit the earth terminal (
)
and the S terminal on the terminal block (TB7) on the out-
door unit whose power jumper connector is mated with
CN40.
3) MA remote controller wiring
Same as 2-7-1
When 2 remote controllers are connected to the sys-
tem
Same as 2-7-1
Group operation of indoor units
Same as 2-7-1
4) LOSSNAY connection
Same as 2-7-2
5) Switch setting
Address setting is required as follows.
(5) Address setting method
The outdoor units in the same refrigerant circuit are automatically designated as OC, OS1, and OS2.
The outdoor units are designated as OC, OS1, and OS2 in the order of capacity from large to small (if two or more units have
the same capacity, in the order of address from small to large).
Proce-
dures
Unit or controller
Address setting
range
Setting method Notes
Factory
setting
1 Indoor
unit Main unit IC 01 to 50 Assign the smallest ad-
dress to the main unit in
the group. To perform a group
operation of indoor
units that have differ-
ent functions, desig-
nate the indoor unit in
the group with the
greatest number of
functions as the main
unit. 00
Sub unit Assign sequential num-
bers starting with the ad-
dress of the main unit in
the same group +1. (Main
unit a1, main unit
a2, main unit ad-
dress +3, etc.)
2 LOSSNAY LC 01 to 50 Assign an arbitrary but
unique address to each of
these units after assigning
an address to all indoor
units. None of these ad-
dresses may overlap
any of the indoor unit
addresses. 00
3 MA
re-
mote
con-
troller Main
remote
controller MA No
settings required. - Main
Sub
remote
controller MA Sub
remote controller Settings to be made ac-
cording to the remote con-
troller function selection
4 Outdoor unit OC
OS1
OS2 51 to 100 Assign sequential address
to the outdoor units in the
same refrigerant circuit.
The outdoor units are au-
tomatically designated as
OC, OS1, and OS2.
(Note) To set the address to
100, set the rotary
switches to 50. 00