6 Installation
Installer and user reference guide
34
RYYQ+RYMQ+RXYQ8~20U7Y1B
VRV IV+ heat pump
4P546228-1 – 2018.09
WARNING
▪ After finishing the electrical work, confirm that each
electrical component and terminal inside the electrical
components box is connected securely.
▪ Make sure all covers are closed before starting up the
unit.
NOTICE
Do NOT operate the unit until the refrigerant piping is
complete. Running the unit before the piping is ready will
break the compressor.
NOTICE
If the power supply has a missing or wrong N-phase,
equipment will break down.
NOTICE
Do NOT install a phase advancing capacitor, because this
unit is equipped with an inverter. A phase advancing
capacitor will reduce performance and may cause
accidents.
NOTICE
NEVER remove a thermistor, sensor, etc., when
connecting power wiring and transmission wiring. (If
operated without thermistor, sensor, etc., the compressor
may break down.)
NOTICE
▪ The reversed phase protection detector of this product
only
functions
when
the
product
starts
up.
Consequently reversed phase detection is not
performed during normal operation of the product.
▪ The reversed phase protection detector is designed to
stop the product in the event of an abnormality when
the product is started up.
▪ Replace 2 of the 3 phases (L1, L2, and L3) during
reverse-phase protection abnormality.
NOTICE
Only applicable if the power supply is three‑phase, and the
compressor has an ON/OFF starting method.
If there exists the possibility of reversed phase after a
momentary black out and the power goes on and off while
the product is operating, attach a reversed phase
protection circuit locally. Running the product in reversed
phase can break the compressor and other parts.
6.8.2
Field wiring: Overview
Field wiring consists of power supply (always including earth) and
indoor-outdoor communication (= transmission) wiring.
Example:
a
b
d
d
d
c
b
g
g
h
h
c
f
f
f
h
e
e
e
a
h
h
h
h
h
i
a
Field power supply (with earth leakage protector)
b
Main switch
c
Earth connection
d
Outdoor unit
e
Indoor unit
f
User interface
g
Indoor power supply wiring (sheathed cable) (230 V)
h
Transmission wiring (sheathed cable) (16 V)
i
Outdoor power supply wiring (sheathed cable)
Power supply 3N~ 50 Hz
Power supply 1~ 50 Hz
Earth wiring
6.8.3
About the electrical wiring
It is important to keep the power supply and the transmission wiring
separated from each other. In order to avoid any electrical
interference the distance between both wiring should always be at
least 25 mm.
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.
▪ Transmission wiring and power supply wiring may not
touch internal piping (except the inverter PCB cooling
pipe) in order to avoid wire damage due to high
temperature piping.
▪ Firmly close the lid and arrange the electrical wires so
as to prevent the lid or other parts from coming loose.
The transmission wiring outside the unit should be wrapped and
routed together with the field piping.
Field piping can be routed from front or bottom of the unit (going left
or right). Refer to
"6.4.3 To route the refrigerant piping" on page 22
▪ Be sure to follow the limits below. If the unit-to-unit cables are
beyond these limits, it may result in malfunction of transmission:
▪ Maximum wiring length: 1000 m.
▪ Total wiring length: 2000 m.
▪ Maximum inter unit wiring length between outdoor units: 30 m.
▪ Transmission wiring to cool/heat selector: 500 m.
▪ Maximum number of branches: 16.
▪ Maximum number of independent interconnectable systems: 10.
▪ Up to 16 branches are possible for unit-to-unit cabling. No
branching is allowed after branching (see figure below).
a
a
a
A
B
b
b
b
b
b
b
h
e
f
g
g
d
c
a
Outdoor unit
b
Indoor 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
