Wiring Of Transmission Cables - Mitsubishi Electric CITY MULTI PUMY-71 Manuel D'installation

8.4. Wiring of transmission cables

Before wiring, check the allowable wiring length. Refer to page 18 for a calculation example of the allowable wiring length.
1 Allowable wiring length
Maximum length of transmission cable: 200 m
Thickness of cable: 1.25 mm 2
2 Types of control signal cable
1. Transmission cable
• Type of transmission cable: Use CVVS or CPEVS for the PUMY-125YMA. For others, carry out wiring according to the table below.
• Diameter of wire: 1.25 mm
System
Transmission cable length
Examples of Houses and individual
applicable places stores where there is lit-
(according to noise) tle noise.
Types of VCTF, VCTFK, CVV,
transmission cable CVS, VVR, VVF, VCT
If the transmission cable is long or a noise source is situated near the unit as in the following cases, installing the unit away from the noise source and
using shielded wires is recommended to prevent noise problems.
• Transmission cable is 120 m or longer.
• The unit is used in places such as office buildings, hospitals and communication offices where noise is expected from equipment such as inverters,
private power generators, high-frequency medical equipment and radio communication devices.
Shielded wires must be used for systems where multiple refrigerants are connected.
3 Wiring example (For wiring example, refer to the remote controller Installation Manual (sold separately).)
Typical wiring examples are shown on page 18.
• Controller name, symbol and allowable number of controllers.
Name Symbol
Outdoor unit controller OC
Indoor unit controller IC
RC
Remote controller (M-NET)
MA
<Wiring Method and Address Settings>
a. Always use shielded wire when making connections between the outdoor unit (OC) and the indoor unit (IC), as well for all OC-OC, and IC-IC wiring
intervals.
b. Use feed wiring to connect terminals M1 and M2 and the ground terminal on the transmission cable terminal block (TB3) of each outdoor unit (OC)
to terminals M1, M2 and terminal S on the transmission cable block of the indoor unit (IC).
c. Connect terminals 1 (M1) and 2 (M2) on the transmission cable terminal block of the indoor unit (IC) that has the most recent address within the
same group to the terminal block on the remote controller (RC).
d. Connect together terminals M1, M2 and terminal S on the terminal block for central control (TB7) for the outdoor unit (OC).
e. On one outdoor unit only, change the jumper connector on the control panel from CN41 to CN40.
f. Connect the terminal S on the terminal block for central control (TB7) for the outdoor unit (OC) for the unit into which the jumper connector was
inserted into CN40 in Step above to the ground terminal
g. Set the address setting switch as follows.
* To set the outdoor unit address to 100, the outdoor address setting switch must be set to 50.
Unit Range
IC (Main) 01 to 50
IC (Sub) 01 to 50
Outdoor Unit 51 to 100
M-NET R/C (Main) 101 to 150
M-NET R/C (Sub) 151 to 200
MA R/C
h. The group setting operations among the multiple indoor units is done by the remote controller (RC) after the electrical power has been turned on.
2
Single refrigerant system
Below 120 m
Places such as office buildings, clin-
ics, hospitals and communication
offices, where noise is expected from
equipment such as inverters, private
power generators, high-frequency
medical equipment and radio com-
munication devices
Number of connectable units
1 to 8 units for each OC (1 to 4 units in the case of 71)
Maximum 2 units for each group.
Maximum 8 units for each OC (for PUMY-71VM)
Maximum 10 units for each OC (for PUMY-125VM)
Maximum 16 units for each OC (for PUMY-125YM(A))
Maximum 2 units for each group.
in the electrical component box.
Use the most recent address within the same group of indoor units
Use an address, other than that of the IC (Main) from among the units within the same group of indoor units.
This must be in sequence with the IC (Main)
Use the most recent address of all the indoor units plus 50
Set at an IC (Main) address within the same group plus 100
Set at an IC (Main) address within the same group plus 150
– Unnecessary address setting (Necessary main/sub setting)
120 m or more
All places
Shielded wire CVVS,CPEVS
Setting Method
Multiple refrigerant system
Irrespective of length
17