15 Electrical installation
Installation and operation manual
31
BS4~12A14AJV1B
VRV 5 branch selector unit
4P670163-1 – 2022.02
14.3.2
To braze the pipe end
NOTICE
Precautions when connecting field piping. Add brazing
material as shown in the figure.
1
1
1
1
2
2
≤Ø25.4
>Ø25.4
▪ When brazing, blow through with nitrogen to prevent creation of
large quantities of oxidised film on the inside of the piping. This
film adversely affects valves and compressors in the refrigerating
system and prevents proper operation.
▪ Set the nitrogen pressure to 20 kPa (0.2 bar) (just enough so it
can be felt on the skin) with a pressure-reducing valve.
a
b
c
d
e
f
f
a
Refrigerant piping
b
Part to be brazed
c
Taping
d
Manual valve
e
Pressure-reducing valve
f
Nitrogen
▪ Do NOT use anti-oxidants when brazing pipe joints.
Residue can clog pipes and break equipment.
▪ Do NOT use flux when brazing copper-to-copper refrigerant
piping. Use phosphor copper brazing filler alloy (BCuP), which
does NOT require flux.
Flux has an extremely harmful influence on refrigerant piping
systems. For instance, if chlorine based flux is used, it will cause
pipe corrosion or, in particular, if the flux contains fluorine, it will
deteriorate the refrigerant oil.
▪ ALWAYS protect the surrounding surfaces (e.g. insulation foam)
from heat when brazing.
15
Electrical installation
CAUTION
See
"2 Specific installer safety instructions"
6] to make
sure this installation complies with all safety regulations.
15.1
Specifications of standard wiring
components
Field wiring consists of:
▪ power supply wiring (including earth),
▪ DIII transmission wiring between units.
NOTICE
▪ Be sure to keep the power line and transmission line
apart from each other. Transmission wiring and power
supply wiring may cross, but may NOT run parallel.
▪ In order to avoid any electrical interference the distance
between both wirings should ALWAYS be at least
50 mm.
Power supply wiring
The power supply wiring must be protected with the required safety
devices, i.e. a main switch, a slow blow fuse on each phase and an
earth leakage protector in accordance with the applicable legislation.
Selection and sizing of the wiring should be done in accordance with
the applicable legislation based on the information mentioned in the
table below.
Component
Unit
BS4A
BS6A
BS8A BS10A BS12A
Power
supply cable
MCA
(a)
0.5
0.6
0.8
1.0
1.1
Voltage
220-240 V
Phase
1~
Frequency
50 Hz
Recommended field fuse
6 A
Residual current device
Must comply with applicable legislation.
(a)
MCA=Minimum circuit ampacity. Stated values are maximum
values.
Transmission wiring
The transmission wiring outside the unit should be wrapped and
routed together with the field piping. See
"15.3 To finish the electrical
33] for more information.
Transmission wiring specification and limits
(a)
Vinyl cords with 0.75 to 1.25 mm² sheath or cables (2‑core wires)
Maximum wiring length between BS unit and indoor
units
1000 m
Maximum wiring length between BS unit and
outdoor unit
1000 m
Maximum wiring length between BS units
1000 m
Total wiring length
2000 m
(a)
If the total transmission wiring exceeds these limits,
communication errors might occur.
Up to 16 branches are possible for unit-unit cabling. No secondary
branchings are allowed after any transmission wire branching.
a
a
A
B
b
b
b
b
b
b
h
e
f
g
g
d
c
a
Outdoor unit
b
Indoor unit + BS unit
c
Main line
d
Branch line 1
e
Branch line 2
f
Branch line 3
g
No branch is allowed after branch
h
Central user interface (etc. …)
A
Outdoor/indoor transmission wiring
B
Master/slave transmission wiring
