Types And Maximum Allowable Length Of Cables - Mitsubishi Electric PUHY-P250YNW-A Service Handbook

[2-2 Types and Maximum Allowable Length of Cables ]

2-2

Types and Maximum Allowable Length of Cables

1. Wiring work
(1) Notes
1) Have all electrical work performed by an authorized electrician according to the local regulations and instructions in this man-
ual.
2) Install external transmission cables at least 5cm [1-31/32"] away from the power supply cable to avoid noise interference.
(Do not put the control cable and power supply cable in the same conduit tube.)
3) Provide grounding for the outdoor unit as required.
4) Run the cable from the electric box of the indoor or outdoor unit in such way that the box is accessible for servicing.
5) Do not connect power supply wiring to the terminal block for transmission cable. Doing so will damage the electronic compo-
nents on the terminal block.
6) Use 2-core shielded cables as transmission cables.
Do not use a single multiple-core cable to connect indoor units that belong to different refrigerant systems. Doing so may result
in signal transmission errors and malfunctions..
Outdoor unit
TB3
TB7
Outdoor unit
TB3
TB7
2-core shielded cable
7) When extending the transmission cable, be sure to extend the shield wire.
(2) Control wiring
Different types of control wiring are used for different systems. Before performing wiring work, refer to the following page(s).
[2-7 Example System with an MA Remote Controller]
Types and maximum allowable length of cables
Control lines are categorized into 2 types: transmission line and remote controller line.
Use the appropriate type of cables and observe the maximum allowable length specified for a given system. If a given system
has a long transmission line or if a noise source is located near the unit, place the unit away from the noise source to reduce
noise interference.
1) M-NET transmission line
Facility
type
Type
Cable type
Number of
cores
Cable size
Maximum transmission
line distance between the
outdoor unit and the far-
thest indoor unit
Maximum transmission
line distance for central-
ized control and Indoor/
outdoor transmission line
(Maximum line distance
via outdoor unit)
2
- chapter 2
Indoor unit
2-core shielded cable
Indoor unit
TB3:Terminal block for transmission line connection
TB7:Terminal block for transmission line for centralized control
500m [1640ft] max.
*The maximum overall line length from the power supply unit on the transmission lines for
centralized control to each outdoor unit or to the system controller is 200m [656ft] max.
Outdoor unit
TB3
TB7
multiple-core cable
TB3
TB7
All facility types
Shielded cable CVVS, CPEVS, MVVS
2-core cable
2
Larger than 1.25mm [AWG16]
200 m [656ft] max.
Indoor unit
Indoor unit
BS_02_C