Wiring Connection; General Wiring Precautions; Wire Specification - McQuay MDS 30 Installation Manual


Matching screw specification.
Diameter
mm
Ф6.35
Ф9.52
Ф12.7
Ф15.88
Ф19.05

When connecting the liquid piping and liquid ball valve, use wrench to fix tightly and ensure they are in the
same axial.
Outside diameter(mm)
Ф6.35
Ф9.52
Ф12.7
Ф15.88
Ф19.05

7.0 Wiring Connection

7.1 General wiring precautions


Power of indoor and outdoor units must be supplied simultaneously.

Cable for power and communication should be designed in parallel and maintain a distance of more than
20cm between them.

Communication cable should be screened to avoid interference of strong signal. Total wire length should be
less than 1000m.

Signal wire has two poles of A and B the same pole must be connected in one connection (A to A, B to B).

Screened layer of signal wires should be earthed.

Outdoor units use either 3 phase or single phase supply (depends on model) while indoor units use only
single phase power cable.

Wiring diagram can be obtained within the units.

7.2 Wire specification


For communication wire, please use below standard.
A: conducting wiring (copper, intersection surface is more than 0.5mm
B: Insulation material
:
C Screen layer (efficiency shall be higher than 95%)
D : outside layer protector (PVC)

For wiring cable, please refer to UL2547 and UL2791 standard
20
Diameter
inch
1/4"
17.0
3/8"
22.0
1/2"
24.0
5/8"
27.0
3/4"
36.0
Moment(N.m)
14~18
35~42
50~57.5
75~80
100~140
(unit: mm)
diameter
angle (˚ )
60~90
60~90
30~60
30~60
20~35
Wiring cable
2
or 20AWG)
Installation Manual IM-MDS_(i)