Daikin BRR9B1V1 User manual

Installation manual
Communication box
BRR9B1V1

Table of contents
Installation manual
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BRR9B1V1
Communication box
4P617761-1 – 2020.04
Table of contents
1 About the documentation 3
1.1 About this document ...................................................................................................................................................... 3
2 General safety precautions 4
2.1 About the documentation .............................................................................................................................................. 4
2.1.1 Meaning of warnings and symbols ................................................................................................................ 4
2.2 For the installer............................................................................................................................................................... 5
2.2.1 General ........................................................................................................................................................... 5
2.2.2 Installation site ............................................................................................................................................... 6
2.2.3 Electrical ......................................................................................................................................................... 7
3 Specific installer safety instructions 9
4 About the box 10
4.1 Communication box........................................................................................................................................................ 10
4.1.1 To remove the accessories from the communication box............................................................................ 10
5 About the communication box 11
5.1 Identification ................................................................................................................................................................... 11
5.1.1 Identification label: Communication box....................................................................................................... 11
6 Unit installation 12
6.1 Preparing the installation site......................................................................................................................................... 12
6.1.1 Installation site requirements of the communication box............................................................................ 12
6.2 Opening and closing the unit.......................................................................................................................................... 13
6.2.1 To open the communication box ................................................................................................................... 13
6.2.2 To close the communication box ................................................................................................................... 13
6.3 Installing the communication box .................................................................................................................................. 13
6.3.1 Precautions when installing the communication box ................................................................................... 13
6.3.2 To install the communication box.................................................................................................................. 14
7 Electrical installation 15
7.1 General overview of the field wiring .............................................................................................................................. 16
7.2 Field wiring: Overview .................................................................................................................................................... 17
7.3 Guidelines when connecting the electrical wiring ......................................................................................................... 17
7.4 Specifications of standard wiring components .............................................................................................................. 18
7.5 To connect the electrical wiring on the communication box ........................................................................................ 19
7.6 To connect the transmission wiring ............................................................................................................................... 20
7.6.1 Between communication box and outdoor unit ........................................................................................... 20
7.6.2 Between communication box and monitoring system.................................................................................. 20
7.7 To fix the wiring cables with cable ties........................................................................................................................... 21
8 Configuration 22
8.1 Setting the addresses of outdoor units and indoor units .............................................................................................. 22
8.2 To set the addresses of the outdoor unit and capacity up unit..................................................................................... 23
8.3 To set the addresses of the indoor units........................................................................................................................ 24
8.4 Configuring the communication box.............................................................................................................................. 24
8.4.1 To configure the communication box PCB for the indoor units.................................................................... 24
8.4.2 To configure the communication box PCB for the outdoor unit and capacity up unit................................. 26
9 Commissioning 30
10 Troubleshooting 31
10.1 Troubleshooting for PCB for indoor unit communication ............................................................................................. 31
10.2 Troubleshooting for PCB for outdoor unit and capacity up unit communication......................................................... 31
11 Technical data 35
11.1 Wiring diagram: Communication box............................................................................................................................. 35
12 Glossary 36

1 | About the documentation
Installation manual
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1 About the documentation
In this chapter
1.1 About this document.............................................................................................................................................................. 3
1.1 About this document
Target audience
Authorised installers
WARNING
Make sure installation, servicing, maintenance, repair and applied materials follow
the instructions from Daikin and, in addition, comply with applicable legislation and
are performed by qualified persons only. In Europe and areas where IEC standards
apply, EN/IEC 60335-2-40 is the applicable standard.
Documentation set
This document is part of a documentation set. The complete set consists of:
▪Installation manual:
-Installation instructions, configuration,…
-Format: Paper (supplied in the kit) + digital files on http://
www.daikineurope.com/support-and-manuals/product-information/
Latest revisions of the supplied documentation may be available on the regional
Daikin website or via your dealer.
The original documentation is written in English. All other languages are
translations.
Technical engineering data
▪A subset of the latest technical data is available on the regional Daikin website
(publicly accessible).
▪The full set of latest technical data is available on the Daikin Business Portal
(authentication required).

2 | General safety precautions
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2 General safety precautions
2.1 About the documentation
▪The original documentation is written in English. All other languages are
translations.
▪The precautions described in this document cover very important topics, follow
them carefully.
▪The installation of the system, and all activities described in the installation
manual and in the installer reference guide MUST be performed by an authorised
installer.
2.1.1 Meaning of warnings and symbols
DANGER
Indicates a situation that results in death or serious injury.
DANGER: RISK OF ELECTROCUTION
Indicates a situation that could result in electrocution.
DANGER: RISK OF BURNING
Indicates a situation that could result in burning because of extreme hot or cold
temperatures.
DANGER: RISK OF EXPLOSION
Indicates a situation that could result in explosion.
WARNING
Indicates a situation that could result in death or serious injury.
WARNING: FLAMMABLE MATERIAL
CAUTION
Indicates a situation that could result in minor or moderate injury.
NOTICE
Indicates a situation that could result in equipment or property damage.
INFORMATION
Indicates useful tips or additional information.
Symbols used on the unit:

2 | General safety precautions
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Symbol Explanation
Before installation, read the installation and operation
manual, and the wiring instruction sheet.
Before performing maintenance and service tasks, read the
service manual.
For more information, see the installer and user reference
guide.
The unit contains rotating parts. Be careful when servicing or
inspecting the unit.
Symbols used in the documentation:
Symbol Explanation
Indicates a figure title or a reference to it.
Example: " 1–3 Figure title" means "Figure 3 in chapter 1".
Indicates a table title or a reference to it.
Example: " 1–3 Table title" means "Table 3 in chapter 1".
2.2 For the installer
2.2.1 General
If you are NOT sure how to install or operate the unit, contact your dealer.
DANGER: RISK OF BURNING
▪Do NOT touch the refrigerant piping, water piping or internal parts during and
immediately after operation. It could be too hot or too cold. Give it time to return
to normal temperature. If you must touch it, wear protective gloves.
▪Do NOT touch any accidental leaking refrigerant.
WARNING
Improper installation or attachment of equipment or accessories could result in
electrical shock, short-circuit, leaks, fire or other damage to the equipment. Only use
accessories, optional equipment and spare parts made or approved by Daikin.
WARNING
Make sure installation, testing and applied materials comply with applicable
legislation (on top of the instructions described in the Daikin documentation).
CAUTION
Wear adequate personal protective equipment (protective gloves, safety glasses,…)
when installing, maintaining or servicing the system.
WARNING
Tear apart and throw away plastic packaging bags so that nobody, especially
children, can play with them. Possible risk: suffocation.

2 | General safety precautions
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WARNING
Provide adequate measures to prevent that the unit can be used as a shelter by small
animals. Small animals that make contact with electrical parts can cause
malfunctions, smoke or fire.
CAUTION
Do NOT touch the air inlet or aluminium fins of the unit.
CAUTION
▪Do NOT place any objects or equipment on top of the unit.
▪Do NOT sit, climb or stand on the unit.
NOTICE
Works executed on the outdoor unit are best done under dry weather conditions to
avoid water ingress.
In accordance with the applicable legislation, it might be necessary to provide a
logbook with the product containing at least: information on maintenance, repair
work, results of tests, stand-by periods,…
Also, at least, following information MUST be provided at an accessible place at the
product:
▪Instructions for shutting down the system in case of an emergency
▪Name and address of fire department, police and hospital
▪Name, address and day and night telephone numbers for obtaining service
In Europe, EN378 provides the necessary guidance for this logbook.
2.2.2 Installation site
▪Provide sufficient space around the unit for servicing and air circulation.
▪Make sure the installation site withstands the weight and vibration of the unit.
▪Make sure the area is well ventilated. Do NOT block any ventilation openings.
▪Make sure the unit is level.
Do NOT install the unit in the following places:
▪In potentially explosive atmospheres.
▪In places where there is machinery that emits electromagnetic waves.
Electromagnetic waves may disturb the control system, and cause malfunction of
the equipment.
▪In places where there is a risk of fire due to the leakage of flammable gases
(example: thinner or gasoline), carbon fibre, ignitable dust.
▪In places where corrosive gas (example: sulphurous acid gas) is produced.
Corrosion of copper pipes or soldered parts may cause the refrigerant to leak.

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2.2.3 Electrical
DANGER: RISK OF ELECTROCUTION
▪Turn OFF all power supply before removing the switch box cover, connecting
electrical wiring or touching electrical parts.
▪Disconnect the power supply for more than 1minute, and measure the voltage at
the terminals of main circuit capacitors or electrical components before servicing.
The voltage MUST be less than 50 V DC before you can touch electrical
components. For the location of the terminals, see the wiring diagram.
▪Do NOT touch electrical components with wet hands.
▪Do NOT leave the unit unattended when the service cover is removed.
WARNING
If NOT factory installed, a main switch or other means for disconnection, having a
contact separation in all poles providing full disconnection under overvoltage
categoryIII condition, MUST be installed in the fixed wiring.
WARNING
▪ONLY use copper wires.
▪Make sure the field wiring complies with the applicable legislation.
▪All field wiring MUST be performed in accordance with the wiring diagram
supplied with the product.
▪NEVER squeeze bundled cables and make sure they do NOT come in contact with
the piping and sharp edges. Make sure no external pressure is applied to the
terminal connections.
▪Make sure to install earth wiring. Do NOT earth the unit to a utility pipe, surge
absorber, or telephone earth. Incomplete earth may cause electrical shock.
▪Make sure to use a dedicated power circuit. NEVER use a power supply shared by
another appliance.
▪Make sure to install the required fuses or circuit breakers.
▪Make sure to install an earth leakage protector. Failure to do so may cause
electrical shock or fire.
▪When installing the earth leakage protector, make sure it is compatible with the
inverter (resistant to high frequency electric noise) to avoid unnecessary opening
of the earth leakage protector.
CAUTION
▪When connecting the power supply: connect the earth cable first, before making
the current-carrying connections.
▪When disconnecting the power supply: disconnect the current-carrying cables
first, before separating the earth connection.
▪The length of the conductors between the power supply stress relief and the
terminal block itself must be as such that the current-carrying wires are tautened
before the earth wire is in case the power supply is pulled loose from the stress
relief.

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NOTICE
Precautions when laying power wiring:
▪Do NOT connect wiring of different thicknesses to the power terminal block (slack
in the power wiring may cause abnormal heat).
▪When connecting wiring which is the same thickness, do as shown in the figure
above.
▪For wiring, use the designated power wire and connect firmly, then secure to
prevent outside pressure being exerted on the terminal board.
▪Use an appropriate screwdriver for tightening the terminal screws. A screwdriver
with a small head will damage the head and make proper tightening impossible.
▪Over-tightening the terminal screws may break them.
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
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.

3 | Specific installer safety instructions
Installation manual
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3 Specific installer safety instructions
Always observe the following safety instructions and regulations.
WARNING
Installation shall be done by an installer, the choice of materials and installation shall
comply with the applicable legislation. In Europe, EN378 is the applicable standard.
WARNING
Provide adequate measures to prevent that the unit can be used as a shelter by small
animals. Small animals that make contact with electrical parts can cause
malfunctions, smoke or fire.
WARNING
▪Make sure the electrical wiring does NOT obstruct correct reattachment of the
communication box cover. Incorrect reattachment of the communication box
cover might result in electrical shocks, fire, or terminal overheating.
▪Do NOT connect the power supply wires to the terminal block for the
transmission wiring. Incorrect connection is very dangerous, results in damage,
and possible burnout of the electrical components.
▪Do NOT use stranded wires with a solder finish applied. A loose wire or other
abnormalities might cause abnormal heating.
WARNING
▪When opening the front plate of an outdoor unit during operation, be careful of a
rotating fan. The fan continues rotating for a while even after the operation is
stopped.
▪Before turning ON the power supply, make sure that the operation switch of the
outdoor unit is turned OFF. You can check this via the inspection hole of the
electrical component box (middle) of the outdoor unit.
▪After turning ON the power supply, operate the push buttons and check the LED
indication via the inspection hole of the electrical component box (middle) of the
outdoor unit. Operating with the cover open might cause an electrical shock.
▪For more information on how to configure the monitoring system (field supply),
see the manual of the supplier.
WARNING
▪Do NOT turn ON the power when the communication box cover is open. An
electrical shock might occur.
▪Before turning ON the power, make sure that the communication box cover is
closed.
CAUTION: Precautions when setting the slave address
▪Do NOT set the same slave address for devices connected to the Modbus master
device.
▪Apart from the slave address set in the communication box, there are 2 other
slave addresses that cannot be set. When the slave address on the PCB for the
outdoor unit (A2P) is set to "A", slave addresses "A+1" and "A+2" CANNOT be set.
Slave address "A" is used for the outdoor unit, "A+1" is used for the capacity up
unit, and "A+2" may NOT be used.

4 | About the box
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4 About the box
In this chapter
4.1 Communication box................................................................................................................................................................ 10
4.1.1 To remove the accessories from the communication box.................................................................................... 10
4.1 Communication box
4.1.1 To remove the accessories from the communication box
×1
×2
aInstallation manual
bCable tie (2×)

5 | About the communication box
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5 About the communication box
Use the communication box only in combination with the following models
(outdoor unit and capacity up unit). Do NOT connect it to any other model.
Used terms Model name
Communication box BRR9B1V1
Outdoor unit LRYEN10A7Y1
Capacity up unit LRNUN5A7Y1
The communication box contains 2 PCBs (A1P and A2P). The A1P PCB makes
communication possible between the communication box and the indoor unit. The
A2P PCB makes communication possible between the communication box and the
outdoor unit and capacity up unit.
Communication settings (slave address, baud rate, parity and stop bits) MUST be
made for A1P and A2P, respectively.
In this chapter
5.1 Identification........................................................................................................................................................................... 11
5.1.1 Identification label: Communication box .............................................................................................................. 11
5.1 Identification
NOTICE
When installing or servicing several units at the same time, make sure NOT to switch
the service panels between different models.
5.1.1 Identification label: Communication box
Location

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6 Unit installation
WARNING
Installation shall be done by an installer, the choice of materials and installation shall
comply with the applicable legislation. In Europe, EN378 is the applicable standard.
In this chapter
6.1 Preparing the installation site ................................................................................................................................................ 12
6.1.1 Installation site requirements of the communication box.................................................................................... 12
6.2 Opening and closing the unit ................................................................................................................................................. 13
6.2.1 To open the communication box........................................................................................................................... 13
6.2.2 To close the communication box........................................................................................................................... 13
6.3 Installing the communication box.......................................................................................................................................... 13
6.3.1 Precautions when installing the communication box ........................................................................................... 13
6.3.2 To install the communication box ......................................................................................................................... 14
6.1 Preparing the installation site
6.1.1 Installation site requirements of the communication box
INFORMATION
Also read the precautions and requirements in the "General safety precautions"
chapter.
▪Mind the following spacing installation guidelines:
≥100 mm ≥50 mm
≥300 mm
≥50 mm ≥50 mm
▪The communication box is designed for indoor installation only and for ambient
temperatures ranging from –5~35°C.
Do NOT install the unit in places such as:
▪In places where a mineral oil mist, spray or vapour may be present in the
atmosphere. Plastic parts may deteriorate and fall off or cause water leakage.
▪Sound sensitive areas (e.g. near a bedroom), so that the operation noise will
cause no trouble.
▪In places with high humidity (max. RH=80%), for example a bathroom.
▪In places where voltage fluctuates a lot.

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▪In places where there is machinery that emits electromagnetic waves.
Electromagnetic waves may disturb the control system, and cause malfunction of
the equipment.
▪In places where there is a risk of fire due to the leakage of flammable gases
(example: thinner or gasoline), carbon fibre, ignitable dust.
WARNING
Provide adequate measures to prevent that the unit can be used as a shelter by small
animals. Small animals that make contact with electrical parts can cause
malfunctions, smoke or fire.
6.2 Opening and closing the unit
6.2.1 To open the communication box
4×
6.2.2 To close the communication box
4×
6.3 Installing the communication box
6.3.1 Precautions when installing the communication box
INFORMATION
Also read the precautions and requirements in the following chapters:
▪General safety precautions
▪Preparation

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6.3.2 To install the communication box
1Drill 4 holes at the fixing points.
a
a
aa
515
529
100
120
b
40
87
(mm)
aHole for a M5 self-tapping screw (4 fixing points)
bWiring intake
2Secure the communication box using 4 screws (field supply).
INFORMATION
Install the communication box on a sufficiently strong wall using fixing screws (field
supply) suitable for the wall.
INFORMATION
▪Make sure that the wiring intakes face downward.
▪Make sure that dew or rainwater will not drop on the field wiring.
▪Provide traps in front of the wiring intakes.

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7 Electrical installation
In this chapter
7.1 General overview of the field wiring...................................................................................................................................... 16
7.2 Field wiring: Overview ............................................................................................................................................................ 17
7.3 Guidelines when connecting the electrical wiring................................................................................................................. 17
7.4 Specifications of standard wiring components...................................................................................................................... 18
7.5 To connect the electrical wiring on the communication box................................................................................................ 19
7.6 To connect the transmission wiring ....................................................................................................................................... 20
7.6.1 Between communication box and outdoor unit ................................................................................................... 20
7.6.2 Between communication box and monitoring system ......................................................................................... 20
7.7 To fix the wiring cables with cable ties .................................................................................................................................. 21

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7.1 General overview of the field wiring
INFORMATION
Indoor units (air conditioning). This field wiring overview shows only one possible
wiring for the indoor units (air conditioning). For more possibilities, see the indoor
unit manual.
g
F2F1 F1
X1M (A1P)
F2 Q1 Q2
TO
MULTI UNIT
TO
OUT/D UNIT
TO
IN/D UNIT
L1 L2 L3 N
X1M PE X2M
C C1 W1 R P1 P2 21 3
X3M
L N X2M
P1 P2 F1 F2 T1 T2
F2F1 F1
X1M (A1P)
F2 Q1 Q2
TO
MULTI UNIT
TO
OUT/D UNIT
TO
IN/D UNIT
L1 L2 L3 N
X1M PEX4M
C C1 W1 R P1 P2 21 3
X5M
L N X2M
X1M
X1M P1 P2 F1 F2 T1 T2
P1 P2
L N
X1M PEX3M
A+ B- F1 F2
220-240 V AC 220-240 V AC 220-240 V AC
12 V DC 12 V DC 12 V DC 12 V DC
220-240 V AC 220-240 V AC 220-240 V AC 220-240 V AC
1N~ 50 Hz
220-240 V AC
RS-485
DIII
DIII DIII
DIII
DIII
f gf
ded e
a
i
i
b
d1 d2
h
h1 h2
d1 d2
X1M (A1P)
X5M
X4M
X1M
PE
X1M
X3M PE
X1M (A1P)
X2M
X1M X3M
PE
k1
k
l
m
k2
k4
k3
j
3N~ 50 Hz
380-415 V AC
c1
c2
3N~ 50 Hz
380-415 V AC
c1
c2
c1
c2
1N~ 50 Hz
220-240 V AC
c1
c2
aCapacity up unit (LRNUN5A7Y1) iIndoor unit (air conditioning)
bOutdoor unit (LRYEN10A7Y1) jUser interface for indoor units (air conditioning)
c1 Overcurrent fuse (field supply) kSafety system (field supply). Example:
c2 Earth leakage circuit breaker (field supply) k1: Control panel
dAlarm panel (field supply) for: k2: CO2 refrigerant leak detector
d1: Caution output signal k3: Safety alarm (lamp)
d2: Warning output signal k4: Ventilation (natural or mechanical)
eControl panel (field supply) for operation output signal lCommunication box (BRR9B1V1)
fRemote operation switch (field supply) mMonitoring system (field supply)
gRemote low noise switch (field supply)
OFF: normal mode
ON: low noise mode
hOperation permission output signal to expansion valves of all: Wiring:
h1: Blower coils (field supply)
RS-485
RS-485 transmission wiring (mind polarity)
h2: Showcases (field supply)
DIII
DIII transmission wiring (no polarity)

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7.2 Field wiring: Overview
Field wiring consists of:
▪power supply (including earth),
▪DIII transmission wiring between communication box and outdoor unit,
▪RS‑485 transmission wiring between communication box and monitoring system.
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.
Transmission wiring
7‒1 DIII weak current – Transmission wiring between each unit except monitoring system
Transmission wiring specification and limits(a)
Vinyl cords with 0.75 to 1.25mm² sheath or cables (2‑core wires)
Maximum wiring length 1000m
Total wiring length ≤2000m
(a) If the total transmission wiring exceeds these limits, communication errors might occur.
7‒2 RS-485 weak current – Transmission wiring between monitoring system and communication
box
Transmission wiring specification and limits(a)
Vinyl cords with 0.75 to 1.25mm² sheath or cables (2‑core wires)
Maximum wiring length 1200m
(a) If the total transmission wiring exceeds these limits, communication errors might occur.
7.3 Guidelines when connecting the electrical wiring
Keep the following in mind:
▪If stranded conductor wires are used, install a round crimp-style terminal on the
end of the wire. Place the round crimp-style terminal on the wire up to the
covered part and fasten the terminal with the appropriate tool.
b a
aStranded conductor wire
bRound crimp-style terminal
▪Use the following methods for installing wires:

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Wire type Installation method
Single-core wire
c b
c
aa
A
AA´
A´
a Curled single-core wire
b Screw
c Flat washer
Stranded conductor wire
with round crimp-style
terminal
c b ba c
a
B
B
a Terminal
b Screw
c Flat washer
O Allowed
X NOT allowed
7‒3 Tightening torque for power supply
Item Tightening torque (N•m)
Terminal block (X1M) (M4) 1.18~1.44
Earth terminal (M5) 3.02~4.08
7‒4 Tightening torque for transmission wiring
Item Tightening torque (N•m)
Communication box terminal block
(X3M) (M3.5)
0.79~0.97
Outdoor unit terminal block (X1M
(A1P)) (M3.5)
0.80~0.96
7.4 Specifications of standard wiring components
7‒5 Power supply and earth wire
Component Specification
Power supply wire Minimum cable section of 2mm²
(Ø1.6mm)
Power supply wire – maximum wiring length 250m
Earth wire 2mm2 (Ø1.6mm)

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7.5 To connect the electrical wiring on the communication box
WARNING
▪Make sure the electrical wiring does NOT obstruct correct reattachment of the
communication box cover. Incorrect reattachment of the communication box
cover might result in electrical shocks, fire, or terminal overheating.
▪Do NOT connect the power supply wires to the terminal block for the
transmission wiring. Incorrect connection is very dangerous, results in damage,
and possible burnout of the electrical components.
▪Do NOT use stranded wires with a solder finish applied. A loose wire or other
abnormalities might cause abnormal heating.
See also "7.1General overview of the field wiring"[416].
1Insert the wiring in the intake hole from the bottom of the communication
box.
a
aIntake hole
2Remove the sheath of the transmission cables.
3Twist the transmission cables.
4Connect the power supply to the terminal block (X1M) of the communication
box.
m
kj
l
j
≥50 mm
h
gi
A1P A2P
d
e
f
n
o
p
n
o
p
7±2 mm
a
X1M
c
b
aSheath
bTwist together before connecting.
cConnect to X1M.
dRound crimp-style terminal
eInsulation sleeve
fWire
gRound crimp-style terminal
hCutout section
iCup washer
jWiring intake
kTransmission wiring (RS‑485 weak current) to the monitoring system (mind polarity)
lTransmission wiring (DIII weak current) to outdoor unit (no polarity)
mPower wire and earth wire (copper)
nCable clamp
oCable tie
pWiring
5Connect the earth wire to the earth terminal.
6Connect the transmission wiring as described in "7.6 To connect the
transmission wiring"[420].

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7.6 To connect the transmission wiring
7.6.1 Between communication box and outdoor unit
INFORMATION
▪Mind the maximum length of the transmission wiring. Otherwise transmission
errors might occur.
▪Use sheathed vinyl cords or cables (2 cores).
▪Use ONLY 2-core cables. Do NOT use cables with 3 or more cores, otherwise
transmission errors might occur.
Prerequisite: Use DIII weak current wire.
Prerequisite: Cut the end portion of the transmission wiring that has to be
connected. Strip insulation from the wire before connecting it to the terminal block
(X3M).
Prerequisite: Twist the wires together before connecting the wires.
1Connect F1 and F2 of the X3M terminal block of the communication box to F1
and F2 (TO OUT/D UNIT) of the X1M (A1P) terminal block of the outdoor unit.
2Connect F1 and F2 (TO OUT/D UNIT) of the X1M (A1P) terminal block of the
outdoor unit to F1 and F2, respectively, of the terminal block of the capacity
up unit.
7±2 mm
a
X3M
c
b
7‒1 Cut, twist, and connect the wire to the terminal block
aSheath
bTwist together before connecting.
cConnect to X3M.
7.6.2 Between communication box and monitoring system
NOTICE
Mind the polarity of the transmission wiring.
See also "7.1General overview of the field wiring"[416].
Prerequisite: Use RS‑485 weak current wire.
Prerequisite: Cut the end portion of the transmission wiring that has to be
connected. Strip insulation from the wire before connecting it to the terminal block
(X3M).
Prerequisite: Use wires with the same diameter and twist the core wires together
before connecting the wires.
1Connect wires from A+ and B– of the terminal block of the communication box
to the monitoring system.
2Connect the wires to the X3M terminal block in the same way as
"7.6.1Between communication box and outdoor unit"[420].