Wiring (For Details, Refer To The Installation Manual Of Each Unit And Controller.); Caution; Control Box And Connecting Position Of Wiring; Wiring Transmission Cables - Mitsubishi Electric City Multi PQHY-P-YLM-A series Installationshandbuch

11. Wiring (For details, refer to the installation manual of each unit and controller.)

11.1. 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 Control wiring (hereinafter referred to as transmission line) shall be 5 cm [2
in] or more apart from power source wiring so that it is not affected by electric
noise from power source wiring (Do not insert transmission line and power
source wire in the same conduit).
3 Provide designated earthing work to the heat source unit.
4 Include some allowance to wiring for the electrical control box on the indoor
and heat source units, because these boxes are sometimes removed at the
time of service work.
5 Never connect the main power source to the terminal block of the
transmission line. If connected, electrical parts will be damaged.
11.2. Control box and connecting position
of wiring
1 Heat source unit
1. Remove the front panel of the heat source unit by unscrewing the screws,
and pushing it up, then pulling it out.
2. Connect the indoor - heat source transmission line to the terminal block
(TB3).
If multiple heat source units are connected in the same refrigerant system,
daisy-chain TB3 (M1, M2, Terminal) on the heat source units. Connect
the indoor - heat source transmission line to TB3 (M1, M2,
only one of the heat source units.
3. Connect the transmission lines for centralized control (between the
centralized control system and the heat source unit of different refrigerant
systems) to the terminal block for centralized control (TB7). If the multiple
heat source units are connected to the same refrigerant system, daisy-chain
TB7 (M1, M2, S Terminal) on the heat source units. (*1)
*1: If TB7 on the heat source unit in the same refrigerant system is not
daisy-chained, connect the transmission line for centralized control to
TB7 on the OC (*2). If the OC is out of order, or if the centralized control
is being conducted during the power supply shut-off, daisy-chain TB7
on the OC and OS (In the case that the heat source unit whose power
supply connector CN41 on the control board has been replaced with
CN40 is out of order or the power is shut-off, centralized control will not
be conducted even when TB7 is daisy-chained).
*2: OC and OS of the heat source units in the same refrigerant system are
automatically identified. They are identified as OC and OS in descending
order of capacity (If the capacity is the same, they will be in ascending
order of their address number).
4. The indoor-heat source transmission line, connect the shield earth to the
). For the centralized transmission lines, connect to the
earth terminal (
shield terminal (S) on the terminal block (TB7). If the heat source units
whose power supply connector CN41 is replaced with CN40, short circuit the
shield terminal (S) and the earth terminal (
5. Attach the connected wires securely with the cable strap at the bottom of the
terminal block. External force applied to the terminal block may damage it,
resulting in a short circuit, earth fault, or a fire.
Caution:
Tighten terminal screws to the specified torque.
- Poor wire contact caused by loose screws may result in overheating and
resultant fire.
- The use of the unit with a damaged circuit board may result in overheating and
resultant fire.
Note:
• Tighten terminal screws to the specified torque. (*1)
*1: Terminal block (TB1 (TLMU: M8 screw)) : 6 ~ 15 [N·m]
Terminal block (TB1 (YLMU: M6 screw)) : 2.5 ~ 2.9 [N·m]
Terminal block (TB3, TB7 (M3.5 screw)) : 0.82 ~ 1.0 [N·m]
• Make sure that the spring washers are parallel to the terminal block.
• Make sure that the wires are securely fastened to the terminal screws.
• Drive the screws straight down, and use caution not to damage the
screw heads.
• Install the ring terminals back to back so that the screws can be driven
straight down.
• Make an alignment mark with a permanent marker across the screw
head, washer, and terminal after tightening the screws.
Terminal) of
) in addition to the above.
6 Use 2-core shield cable for the transmission line. If transmission lines of
different systems are wired with the same multiplecore cable, the resultant
poor transmitting and receiving will cause erroneous operations.
7 Only the transmission line specified should be connected to the terminal
block for heat source unit transmission.
The system will not operate with improper connection.
8 In the case of connecting a system controller or to conducting group
operation in different refrigerant systems, a transmission line is required
between the heat source units in different refrigerant systems.
Connect the transmission between the terminal blocks for centralized control
(two-wire line with no polarity).
9 Use the remote controller to set the groups.
[Fig. 11.2.1] (P.14)
A Power source
C Earth terminal
[Fig. 11.2.2] (P.14)
A Terminal block with loose screws
C Spring washers must be parallel to the terminal block.
[Fig. 11.2.3] (P.14)
A Power wires, transmission lines
C Terminal blocks (TB1, TB3, TB7)
E Install the ring terminals back to back.
[Fig. 11.2.4] (P.14)
A Cable strap
C Earth terminal for field wiring connection
2 Conduit tube installation
• Hammer the knockout holes for the conduit tube located on the base and the
bottom part of the front panel.
• When installing the conduit tube directly through the knockout holes, remove
burrs and protect the tube with masking tape.
• Use the conduit tube to narrow the opening if there is a possibility of small
animals entering the unit.

11.3. Wiring transmission cables

1 Types of control cables
1. Wiring transmission cables
• Types of transmission cables: Shielding wire CVVS, CPEVS or MVVS
• Cable diameter: More than 1.25 mm
• Maximum wiring length: Within 200 m [656 ft]
• Maximum length of transmission lines for centralized control and indoor/heat
source transmission lines: 500 m [1640 ft] at the maximum
The maximum length of wiring between power supply unit for transmission
lines (for centralized control), and each heat source unit and system controller
is 200 m [656 ft].
2. Remote control cables
• ME Remote Controller
Sheathed 2-core cable
Type of remote control cable
(CVV, shielded CVVS, CPEVS, or MVVS)
0.3 to 1.25 mm
Cable diameter
(0.75 to 1.25 mm
When 10 m [32 ft] is exceeded, use cable
Remarks with the same specifications as 1. Wiring
transmission cables.
* Connected with simple remote controller.
CVVS, MVVS: PVC insulated PVC jacketed shielded control cable
CPEVS: PE insulated PVC jacketed shielded communication cable
CVV: PVC insulated PVC sheathed control cable
• MA Remote Controller
Type of remote control cable Sheathed 2-core cable (unshielded) CVV
0.3 to 1.25 mm
Cable diameter
(0.75 to 1.25 mm
Remarks Within 200 m [656 ft]
* Connected with simple remote controller.
B Transmission line
B Properly installed terminal block
B Daisy-chain (transmission lines only)
D Make an alignment mark.
B Power source cable
[AWG16]
2
[AWG 22 to 16]
2
[AWG 18 to 16])*
2
[AWG 22 to 16]
2
[AWG 18 to 16])*
2
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