Mitsubishi P120 User Manual

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II  Restrictions ]
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HWE09120
GB
[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 line. Doing so will damage the electronic compo-
nents on the terminal block.
6)   Use 2-core shielded cables as transmission cables.
Use a separate 2-core control cable for each refrigerant system. Do not use a single multiple-core cable to connect indoor 
units that belong to different refrigerant systems. The use of a multiple-core cable may result in signal transmission errors and 
malfunctions.
(2) Control wiring
Different types of control wiring are used for different systems. 
Refer to section "[5] An Example of a System to which an MA Remote Controller is connected - [7] An Example of a System 
to which both MA Remote Controller and ME Remote Controller are connected" before performing wiring work.
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
Cable type
Facility 
type
All facility types
Type
Shielded cable CVVS, CPEVS, MVVS
Number of 
cores
2-core cable
Cable size
Larger than 1.25mm
2
  [AWG16]
Maximum transmission 
line distance between the 
outdoor unit and the far-
thest indoor unit
200 m [656ft] max.
Maximum transmission 
line distance for central-
ized control and Indoor/
outdoor transmission line
(Maximum line distance 
via outdoor unit)
500 m [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.
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2-core shielded cable 
2-core shielded cable 
Indoor unit 
Outdoor unit 
TB3: Terminal block for indoor-outdoor transmission line  TB7: Terminal block for centralized control 
Remote Controller 
Indoor unit 
Outdoor unit 
Remote Controller 
multiple-core cable