6. Electrical work
6.1. Caution
1 Follow ordinance of your governmental organization for technical standard
related to electrical equipment, wiring regulations and guidance of each electric
power company.
2 Use self-extinguishing distribution cables for power supply wiring.
3 Wiring for control (hereinafter referred to as transmission line) shall be (5 cm
[2 inch] or more) apart from power source wiring so that it is not influenced by
electric noise from power source wiring. (Do not insert transmission line and
power source wire in the same conduit.)
4 Be sure to provide designated grounding work to outdoor unit.
5 Give some allowance to wiring for electrical part box of indoor and outdoor
units, because the box is sometimes removed at the time of service work.
6 Never connect the main power source to terminal block of transmission line. If
connected, electrical parts will be burnt out.
7 Use 2-core shield cable for transmission line. If transmission lines of different
systems are wired with the same multiplecore cable, the resultant poor trans-
mitting and receiving will cause erroneous operations.
E
L1 L2 L3
TB1
A
A Power source
B Power supply for branch box
C Screw on the electrical component box
for ground connection (TB1B)
D Transmission line
K
H
I
J
G Cover panel
H Power supply wire for outdoor unit
I Power supply wire for branch box
J Transmission wire
K Cable clamps
L Conduit plate
Fig. 6-1
Fig. 6-2
M1
M2
S
M1
M2
S
TB3
TB7
D
F
B1
B2
TB1B
B
C
E Screw on the electrical component box
for ground connection (TB3)
F Screw on the electrical component box
for ground connection (TB7)
ø45 [1-25/32] Knock-out hole
(For power supply wires)
G
L
ø22.2 [7/8] Knock-out hole
(For transmission wires)
When connecting wiring to the terminal
block during wiring work, route the wiring
so that it does not come into direct contact
with especially hot parts (such as the 4 way
valve) of the devices inside the outdoor unit.
8 Only the transmission line specified should be connected to the terminal block
for outdoor unit transmission.
(Transmission line to be connected with indoor unit : Terminal block TB3 for
transmission line, Other : Terminal block TB7 for centralized control)
Erroneous connection does not allow the system to operate.
9 In the case to connect with centralized controller or to conduct group opera-
tion in different refrigerant systems, the control line for transmission is required
between the outdoor units each other.
Connect this control line between the terminal blocks for centralized control.
(2-wire line with no polarity)
When conducting group operation in different refrigerant systems without
connecting to centralized controller, replace the insertion of the short circuit
connector from CN41 of one outdoor unit to CN40.
0 Group is set by operating the remote controller.
1 Before turning outdoor unit on, be sure to turn the indoor units and the branch
boxes on.
6.2. Control box and connecting position of wiring
(Fig. 6-1)
1. Connect the wiring between the outdoor unit and the indoor unit or branch box
to the transmission terminal block (TB3) of the outdoor unit.
Connect the wiring between the outdoor unit and the centralized control system
to the transmission terminal block (TB7) of the outdoor unit.
When using shielded wiring, connect the ground of the shielded wiring to the
shield terminal (S) of the terminal block (TB3) or (TB7).
If the connection of the outdoor unit's transmission power supply connector
has been changed from CN41 to CN40, connect the shield terminal (S) of the
terminal block (TB7) to the screw (F) using the grounding lead wire attached
this manual.
* The shield terminal (S) of the transmission terminal block (TB3) is connected to
the ground (E) when the unit is shipped from the factory.
2. Conduit mounting plates are being provided. Remove the knock-out pieces
from the piping cover, pass the power supply and transmission wires through
the appropriate knock-out holes, and connect the wires to the terminal block.
3. The terminal block (TB1B) is for supplying power to the branch box (208/230 V,
max 18A).
4. Fix the power supply and transmission wires using clamps K. Refer to Fig. 6-1.
Caution:
Never connect the transmission line for the branch box or the central control
system transmission line to this terminal block (TB1B). If the transmission
lines are connected, the indoor unit terminal block, branch box terminal block
or centralized control terminal block could be damaged.
en
16