13
GB
4. Wiring cross-sections noted are the minimum values for metal and
plastic wiring conduits (containing up to three cables).
• Power supply cords of appliances shall not be lighter than design 245 IEC 53
or 227 IEC 53.
• A switch with at least 3 mm contact separation in each pole shall be provided
by the Air conditioner installation.
Caution:
1. Use only breakers and fuses of the correct capacity. Use of larger ca-
pacity fuses, or wire may result in a fault and smoke or flames.
2. Wire the power supply so that no tension is imparted. Otherwise dis-
connection, heating or fire result.
3. If the power cable is damaged, it must be replaced by the manufacturer,
its service agent or similarly qualified persons in order to avoid a hazard.
7.2. Connecting remote controller, indoor
and outdoor transmission cables
• Connect indoor unit TB5 and outdoor unit TB3. (Non-polarized 2-wire)
The “S” on indoor unit TB5 is a shielding wire connection. For specifications
about the connecting cables, refer to the outdoor unit installation manual.
• Do not connect the indoor unit terminal block (TB5) to another indoor unit
terminal block (TB5) that is connected to a different outdoor unit.
• Connect terminals M1 and M2 of the terminal block for indoor-outdoor trans
-
mission line (TB3) on the outdoor unit to their respective terminals M1 and
M2 of the terminal block for indoor-outdoor transmission line (TB5) on the
indoor unit. * Only use shielded cables.
• Connect one end of the grounding wire of the shielded cable to the earth
screw of the OC and the other end to the S terminal of terminal block (TB5)
on the indoor unit.
• Daisy-chain terminals M1 and M2 of the terminal block for transmission line
for centralized control (TB7) on each outdoor unit (OC). * Only use shielded
cables.
• Disconnect the male power supply connector from CN41 and connect it to
CN40 on only one outdoor unit.
• Daisy-chain the S terminal of terminal block (TB7) on each outdoor unit with
each other with the grounding wire of the shielded cable.
• Connect the S terminal of terminal block (TB7) on the outdoor unit whose
male power supply switch connector has been connected to CN40 to the
earth terminal on the control box.
• Install a remote controller following the manual supplied with the remote con
-
troller.
• Connect the “1” and “2” on indoor unit TB15 to a MA remote controller. (Non-
polarized 2-wire)
[Fig. 7.2.1] (P.3) MA Remote controller
<A> Model 250
<B> Model 500
A
Terminal block for indoor transmission cable
B
Terminal block for outdoor transmission cable
C
MA Remote controller
• DC 9 to 13 V between 1 and 2 (MA remote controller)
[Fig. 7.2.2] (P.3) MA Remote controller
<A> Model 250
<B> Model 500
A
Non-polarized
B
Upper level
C
Lower level
D
MA Remote Controller
Note:
1. Ensure that the wiring is not pinched when fitting the terminal box
cover. Pinching the wiring may cut it.
2. Put the transmission cable earth via the outdoor unit’s earth terminal
to the ground.
Caution:
Install wiring so that it is not tight and under tension. Wiring under tension
may break, or overheat and burn.
• Fix power source wiring to control box by using buffer bushing for tensile
force. (PG connection or the like.) Connect transmission wiring to transmis
-
sion terminal block through the knockout hole of control box using ordinary
bushing.
• After wiring is complete, make sure again that there is no slack on the con
-
nections, and attach the cover onto the control box in the reverse order re-
moval.
7.3. Connecting electrical connections
(Be sure to prevent terminal screws from loosening.)
Caution:
• Fix the site wiring firmly in place with wiring clamps.
• Ensure that wiring installation work does not result in tension being
applied to the wiring. Such tension may result in breaks in wiring, and
consequent overheating, smoke, or flame.
Step 1. Turn the key in the center of the panel at the bottom of the unit to
open the panel. Next, remove the four screws in the control box
cover to remove the cover.
Step 2. Install electrical wiring, internal and external connecting wiring,
and earth wiring, as shown in [Fig. 7.3.1]. Refer to “7.5. External I/O
Specifications” if installing wiring when external I/O terminals are
used.
Step 3. When wiring is complete, check for less connections and wiring
mistakes, and close the panel.
<In the case of two refrigerant circuits>
Changes to the connector connection and switch settings are required as shown
in [Fig.7.3.2].
[Fig. 7.3.1] (P.4) MA Remote controller
<A> Model 250
<B> Model 500
A
Transformer
B
External I/O board
C
No.1 Transmission line terminal block
D
No.2 Transmission line terminal block (Note: Connect to top terminal block)
E
Connect transmission line to outdoor unit
F
Fix in place after connecting wiring.
G
Earth
H
Fuse
I
Control box
J
Bottom panel
[Fig. 7.3.2] (P.4)
<When connected to a 2-refrigerant circuit>
The unit is shipped ready to be connected to a single-refrigerant circuit.
When connected to a 2-refrigerant circuit, make the connection changes and switch
setting changes (SW 2, 3, and 4 on both No. 1 and No.2 boards) as shown in
[Fig. 7.3.2] on site.
7.4. Setting addresses
(Be sure to operate with the main power turned OFF.)
• There are two types of rotary switch setting available: setting addresses 1 to
9 and over 10.
<How to set addresses>
Example: If Address is “3”, remain SW12 (for over 10) at “0”, and match
SW11(for 1 to 9) with “3”.
Caution:
Setting the address of the indoor unit controller
• For the Model 500
The top side indoor controller address of the indoor unit must always
be odd number. The bottom side indoor controller address must be 1
more than the top side indoor controller address.
• Setting the address of the outdoor unit controller
The address must be 50 more than the address of the indoor units us-
ing the same refrigerant.
* If the address is not correctly set, operation will not run correctly.
After setting the address, enter the set address on the product nameplate on the
front panel using a permanent marker.
• The rotary switches are all set to “0” when shipped from the factory. These
switches can be used to set unit addresses.
• The determination of indoor unit addresses varies with the system at site.
Set them referring to technical data.
• If connecting a controller inside a central controller, the address of the two
controllers inside the Model 500 indoor unit must always be set in the same
group.
[Fig. 7.4.1] (P.5)
• When there is a single Model 250 unit
A
CN41 as it is
*1 The numbers shown in the square (
) are addresses.
*2 The Model 250 indoor unit contains one indoor controller board.
[Fig. 7.4.2] (P.5)
• When there is a single Model 500 unit
A
Replace CN41 with CN40
B
CN41 as it is
* The Model 500 indoor unit contains two indoor controller boards.
[Fig. 7.4.3] (P.5)
• When connected to G-50
A
CN41 as it is
B
Group 1
C
Group 2
D
Power supply unit
E
DC Power supply (DC 12V)
