IntesisBox DK-RC-MBS-1 User manual

IntesisBox®
DK-RC-MBS-1 v.1.6
Modbus RTU (EIA-485) Interface for Daikin air conditioners.
Compatible with VRV and SKY line air conditioners commercialized
by Daikin.
User Manual
Issue Date: 12/2017
r3.3 EN
Order Codes:
DK-RC-MBS-1: Modbus RTU Interface for Daikin air conditioners

DK-RC-MBS-1
User’s Manual r3.3 EN
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This information is subject to change without notice
IntesisBox®is a registered trademark of Intesis Software SLU
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© Intesis Software S.L.U. 2017. All Rights Reserved.
Information in this document is subject to change without notice. No part of this publication
may be reproduced, stored in a retrieval system or transmitted in any form or any means
electronic or mechanical, including photocopying and recording for any purpose other than the
purchaser’s personal use without the written permission of Intesis Software S.L.U.
Intesis Software S.L.U.
Milà i Fontanals, 1 bis
08700 Igualada
Spain
TRADEMARKS
All trademarks and tradenames used in this document are acknowledged to be the copyright of
their respective holders.

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INDEX
1. Presentation .......................................................................................................... 4
2. Connection............................................................................................................ 5
2.1 Connect to the AC indoor unit............................................................................... 5
2.2 Connection to the EIA-485 bus ............................................................................. 6
3. Quick Start Guide................................................................................................... 6
4. Modbus Interface Specification ................................................................................ 7
4.1 Modbus physical layer.......................................................................................... 7
4.2 Modbus Registers................................................................................................ 7
4.2.1 Control and status registers ........................................................................... 7
4.2.2 Configuration Registers.................................................................................. 9
4.2.3 Considerations on Temperature Registers ........................................................ 9
4.3 DIP-switch Configuration Interface ...................................................................... 11
4.4 Implemented Functions ..................................................................................... 15
4.5 Device LED indicator ......................................................................................... 15
4.6 EIA-485 bus. Termination resistors and Fail-Safe Biasing mechanism ...................... 16
5. Electrical and Mechanical features .......................................................................... 17
6. List of supported AC Unit Types. ............................................................................ 18
7. Error Codes ......................................................................................................... 19
8. Annex 1: Master/Slave of Operation Mode............................................................... 23

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1. Presentation
The DK-RC-MBS-1 interfaces allow a complete and natural
integration of Daikin air conditioners into Modbus RTU (EIA-
485) networks.
Compatible with all SKY Air and VRV models commercialized
by Daikin. Check the Section 6 to obtain more information.
Reduced dimensions. 93 x 53 x 58 mm
3.7” x 2.1” x 2.3”
•Quick and easy installation.
Mountable on DIN rail, wall, or even inside the indoor unit on some models of AC.
•External power not required.
•Direct connection to Modbus RTU (EIA-485) networks. Up to 63 DK-RC-MBS-1 devices can
be connected in the same network.
DK-RC-MBS-1 is a Modbus slave device.
•Direct connection to the AC indoor unit. Up to 16 AC indoor units can be connected to DK-
RC-MBS-1, controlling them as one (not individually).
•Configuration from both on-board DIP-switches and Modbus RTU.
•Total Control and Supervision.
•Real states of the AC unit's internal variables.
•Allows simultaneous use of the AC’s remote controls and Modbus RTU.
* Up to 63 IntesisBox devices can be installed in the same Modbus RTU bus. However, depending on the configured speed, the
installation of Modbus Repeaters may be required
•SCADA
•PLC
•DDC
•BMS
•HMI
•Controller
•etc
Up to 63
AC indoor
units*
Modbus RTU
EIA-485 network
Modbus RTU
Master
device
DK-RC-MBS-1
DK-RC-MBS-1
DK-RC-MBS-1

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Connection to
P1P2 bus. Two
wire cable.
90 mm / 3.5”
53 mm / 2.1”
53 mm / 2.1”
90 mm
3.5”
2. Connection
The interface comes with a plug-in terminal block of 2 poles to establish direct connection with
the AC indoor unit. It comes as well with a plug-in terminal block of 2 poles to establish direct
connection with the Modbus RTU EIA-485 network.
2.1 Connect to the AC indoor unit
The DK-RC-MBS-1 connects directly to the Daikin P1P2 Bus, which is not provided within the
interface. Depending on which controllers are available, the recommended connection’methods
are the following ones (details in Figure 2. 1):
•Wired remote control available. Connect the gateway as Slave in parallel with the
wired remote controllers (Controller acts as Master).
•Infrared remote control available. Connect the gateway as Master in parallel with the
infrared remote controller (Infrared Remote Control as Slave).
•No remote control available Connect the gateway directly to the P1P2 bus of the
indoor unit as Master when there is no Daikin Remote Controller.
Maximum P1 P2 bus length is 500 meters / 1,640.42 ft . The bus has no polarity sensitivity.
AC Indoor Unit
IntesisBox®
DK-RC-MBS-1
MODBUS
RTU
EIA-485
Bus
EIA485
A+ B-
P1 P2
AC Unit
For wall mounting
extract the upper
and lower staples
until you hear the
"click".
P1 P2
DAIKIN
Internal
electronic
control
board
Remote Controller
P2
P1
IntesisBox®
DK-RC-MBS-1
MODBUS
RTU
EIA-485
Bus
EIA485
A+ B-
P1 P2
AC Unit
AC Indoor Unit
Internal
electronic
control
board
Connection to P1P2
bus. Two wire cable.
P2
P1
Max. 500m / 1,640.42 ft
Max. 500m / 1,640.42 ft
Figure 2. 1 DK-RC-MBS-1 Connection diagrams

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2.2 Connection to the EIA-485 bus
Connect the EIA-485 bus wires to the plug-in terminal block (the one of two poles) of DK-RC-
MBS-1 and keep the polarity on this connection (A+ and B-). Make sure that the maximum
distance to the bus is 1,200 meters (3,937 ft). Loop or star typologies are not allowed in the
case of the EIA-485 bus. A terminator resistor of 120Ωmust be present at each end of the bus
to avoid signal reflections. The bus needs a fail-safe biasing mechanism (see section 4.6 for
more details).
3. Quick Start Guide
1. Disconnect the air conditioning from the Mains Power.
2. Attach the interface next to the AC indoor unit (wall mounting) following the instructions
of the diagram below or install it inside the AC indoor unit (respect the safety
instructions given).
3. Connect the P1P2 bus between the interface and the AC indoor unit following the
instructions of the diagram. Screw each bare cable end in the corresponding P1P2
terminals of each device.
4. Connect the EIA-485 bus to the connector EIA485 of the interface.
5. Close the AC indoor unit.
6. Check the DIP-Switch configuration of the IntesisBox interface and make sure it matches
the current installation’s parameters (see section 4.3).
By default, the interface is set to:
▪Modbus Slave Address 1
▪Modbus baud rate 9600 bps
These parameters can be modified from SW4 and SW3 DIP-Switches.
All other switch positions are set at low level (Off position ) by default.
NOTE: All changes on the DIP-Switch configuration require a system power cycle to be
applied.
7. Connect the AC system to Mains Power.
IMPORTANT: The IntesisBox interface requires to be connected to the AC unit
(powered) to start communicating.
ON
ON
SW3
SW4

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4. Modbus Interface Specification
4.1 Modbus physical layer
DK-RC-MBS-1 implements a Modbus RTU (Slave) interface, to be connected to an EIA-485 line.
It performs 8N2 communication (8 data bits, no parity and 2 stop bit) with several available
baud rates (2400 bps, 4800 bps, 9600 bps -default-, 19200 bps, 38400 bps, 57600 bps, 76800
bps and 115200 bps). It also supports 8N1 communication (8 data bits, no parity and 1 stop
bit).
4.2 Modbus Registers
All registers are type “16-bit unsigned Holding Register” and they use the standard Modbus big
endian notation.
4.2.1 Control and status registers
Register Address
(protocol address)
Register Address
(PLC address)
R/W
Description
0
1
R/W
AC unit On/Off
▪0: Off
▪1: On
1
2
R/W
AC unit Mode 1
▪0: Auto
▪1: Heat
▪2: Dry
▪3: Fan
▪4: Cool
2
3
R/W
AC unit Fan Speed 1
▪1: Low
▪2: Mid
▪3: High
3
4
R/W
AC unit Vane Position 1
▪1: Position-1 (Horizontal)
▪2: Position-2 (Horizontal)
▪3: Position-3 (Medium)
▪4: Position-4 (Vertical)
▪5: Position-5 (Vertical)
▪10: Swing
4
5
R/W
AC unit Temperature Setpoint 1,2,3
▪-32768 (Initialization value)
▪16..31ºC (ºC/x10ºC)
▪61..92ºF
5
6
R
AC unit Temperature reference 1,2,3
▪-32768 (Initialization value)
▪10..38ºC (ºC/x10ºC)
▪50..100ºF
1
Available values will depend on the AC unit mode. Check the AC unit model functions in its user manual to know the possible values for
this register.
2
Magnitude for this register can be adjusted to Celsius x 1ºC, Celsius x 10ºC (default) or Fahrenheit. See section 4.2.3 for more
information.
3
It is not possible turn to x10 the value shown in Fahrenheit.

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Register Address
(protocol address)
Register Address
(PLC address)
R/W
Description
6
7
R/W
Window Contact
▪0: Closed (Default)
▪1: Open
7
8
R/W
DK-RC-MBS-1 Disablement 4
▪0: DK-RC-MBS-1 enabled (Default value)
▪1: DK-RC-MBS-1 disabled
8
9
R/W
AC Remote Control Disablement 4
▪0: Remote Control enabled (Default value)
▪1: Remote Control disabled
9
10
R/W
AC unit Operation Time 4
▪0..65535 (hours). Counts the time the AC
unit is in “On” state.
10
11
R
AC unit Alarm Status
▪0: No alarm condition
▪1: Alarm condition
11
12
R
Error Code 5
▪0: No error present
▪65535(-1 if it is read as signed value): Error
in the communication of DK-RC-MBS-1 with
the AC unit.
▪Any other error present, see the table at the
end of this document.
22
23
R/W
Indoor unit´s ambient temperature from
external sensor (at Modbus side) 1,2,3,6,7
▪-32768: (Initialization value). No
temperature is being provided from an
external sensor.
▪Any other: (ºC/x10ºC/ºF)
23
24
R
AC Real temperature setpoint 1,2,3,6
▪When no external temperature is provided,
this read-only register will have the same
value as register 5 (PLC addressing). In all
cases, it will show the current setpoint in the
indoor unit.
▪16..31ºC (ºC/x10ºC)
▪60..90ºF
26
27
R/W
AC unit Horizontal Vane Position 1
▪0: Auto (Default Value)
▪10: Swing
55
56
R/W
Under voltage counter 1
▪0..300
97
98
R/W
Block Periodic Sendings 4,8,9
▪0: Non-blocked (Default value)
▪1: Blocked
4
This value is stored in non-volatile memory
5
See section 7 for possible error codes and their explanation
6
See section 4.2.3 for more information
7
This register is available in firmware version 0.8 onwards
8
If the register is configured as “0: Non-blocked”, all commands received from Modbus will be sent to the AC system. If “1: Blocked”,
commands from Modbus will only be sent to the AC system if they differ from the previous value.
9
This register applies to firmware version 1.6 onwards

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4.2.2 Configuration Registers
Register Address
(protocol address)
Register Address
(PLC address)
R/W
Description
13
14
R/W
“Open Window” switch-off timeout 10
▪0..30 (minutes)
▪Factory setting: 30 (minutes)
14
15
R
Modbus RTU baud-rate
▪2400bps
▪4800bps
▪9600bps (Default)
▪19200bps
▪38400bps
▪57600bps
▪76800bps
▪115200bps
15
16
R
Modbus Slave Address
▪1..63
21
22
R
Max number of fan speeds
48
49
R
Switch value
49
50
R
Device ID: 0x0801
50
51
R
Software version
4.2.3 Considerations on Temperature Registers
•AC unit temperature setpoint (R/W)
(register 4 –in Protocol address / register 5 –in PLC address):
This is the adjustable temperature setpoint value that must be required by the user. This
register can be read (Modbus function 3 or 4) or written (Modbus functions 6 or 16). A
remote controller connected to the Daikin indoor unit will report the same temperature
setpoint value as this register, but only will happen when no AC unit´s external
reference is provided from DK-RC-MBS-1 (see detail for register 22/23 below).
•AC unit temperature reference (R)
(register 5 –in Protocol address / register 6 –in PLC address):
This register reports the temperature that is currently used by the Daikin indoor unit as
the reference of its own control loop. Depending on the configuration of the indoor unit,
this value can be the temperature reported by the sensor on the return path of the
Daikin indoor unit or the sensor of its remote controller. It is a read-only register
(Modbus functions 3 or 4).
•AC unit external temperature reference (Modbus) (R/W)
(register 22 –in Protocol address / register 23 –in PLC address):
This register allows us to provide an external temperature’s sensor from the Modbus
side. Daikin indoor unit does not allow on devices like DK-RC-MBS-1 to provide directly
temperature to be used as a reference of the control loop of the AC indoor unit. In order
to overcome this limitation and enable the usage of an external temperature sensor
(i.e.from Modbus side), DK-RC-MBS-1 applies the following mechanism (only if “external
temperature’s reference”is being used):
10
Once window contact is open, a count-down to switch off the AC Unit will start from this configured value.

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oAfter a couple of values have been entered in the “AC unit external temperature’s
reference” (register 22/23) and “AC unit temperature set point” (register 4/5),
DK-RC-MBS-1 is going to estimate the temperature chosen implied (e.g. if a
“temperature setpoint (register 4/5)” of 22ºC, and an “external temperature
reference (register 22/23)” of 20ºC are entered, DK-RC-MBS-1 will assume that
the user is demanding a +2ºC increase in temperature).
oBy knowing at any time the ambient temperature currently used by the indoor
unit to control its own operation (register 5/6), DK-RC-MBS-1 can calculate the
required temperature setpoint needed to apply the decrease/increase on the real
temperature and reach the temperature chosen by the user (following the
example above, if DK-RC-MBS-1 reads an “ambient temperature” (register 5/6)
of 24ºC in the indoor unit, it will apply a final setpoint of 24ºC + 2ºC = 26ºC).
oAt this moment, each time that DK-RC-MBS-1 detects a change on the ambient
temperature reported by the indoor unit (register 5/6), it will also change the
required setpoint, in order to keep the temperature required by the user at any
time. If we follow the last example, if DK-RC-MBS-1 receives a new
temperature´s value coming from the indoor unit of 25ºC, DK-RC-MBS-1 will
automatically adjust the temperature setpoint required of the AC indoor unit to
25ºC + 2ºC = 27ºC).
oIn general, DK-RC-MBS-1 is constantly applying the “Virtual Temperature”
formula:
SAC =Su–( Tu–TAC )
Where:
SAC - setpoint value currently applied to the indoor unit
Su- setpoint value written at Modbus side (register 4/5)
Tu- external temperature reference written at Modbus side (register 22/23)
TAC - ambient temperature that the indoor unit is using as the reference of its
own control loop (register 5/6)
When DK-RC-MBS-1 detects a change in any of the values of
{Su, Tu, TAC }, it will send the new setpoint (SAC) to the indoor unit.
oAfter the startup, the value for “external temperature’s reference” (register
22/23) has a value -32768 (0x8000). This value means that no external
temperature reference is being provided through DK-RC-MBS-1. In this scenario,
the setpoint value shown in register 4/5 is always the same as the current
setpoint value of the indoor unit. The AC indoor unit will use its own return path
temperature sensor as reference for its control loop.
oWhen the mechanism of “Virtual Temperature” is applied. The temperature
setpoint’s value shown by the Remote Controller or other Control System from
Daikin connected to the indoor unit may show a different value from the value
shown in register 4/5.
oIf it is desired to use the temperature’s reading from the Remote Control as the
external temperature reference (Tu,register 22/33), the Remote Controller must
be configured as Master, and the Daikin AC indoor unit must have the option
“thermostat sensor in the Remote Controller”as activated. This configuration is
done via a Daikin Remote Controller connected to the indoor unit and must be
done by Daikin authorized installers while the AC is being installed.

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oWhen DK-RC-MBS-1 is set as “Master” of P1P2 bus, the external temperature’s
sensor connected to Modbus RTU EIA-485 network provides directly the value
currently applied to the indoor unit ( SAC ), and the process of the Virtual
temperature is not applied. In this case, the Remote Controller or any other
Control System connected from Daikin is not able to send the external
temperature reference’s value to the register 22/23.
•AC Real temperature setpoint (R)
(register 23 –In Protocol address / register 24 –in PLC address):
As it has been detailed on the previous point, the real temperature setpoint in the indoor
unit and the temperature setpoint requested from DK-RC-MBS-1 might differ (when a
value in register 22/23 –“external temperature reference” is entered). This register
always informs about the current temperature setpoint which is being used by the indoor
unit –it is also includes the temperature setpoint that will be shown by an additional
remote controller from Daikin connected to the indoor unit, if it is present on the system.
Moreover, notice that temperature’s values of all these four registers are expressed according to
the temperature´s format configured through its onboard DIP-Switches (See “4.3 - DIP-switch
Configuration Interface”). These following formats are possible:
•Celsius value: Value in Modbus register is the temperature value in Celsius (i.e. a
value “22” in the Modbus register must be interpreted as 22ºC)
•Decicelsius value: Value in Modbus register is the temperature value in
decicelsius (i.e. a value “220” in the Modbus register must be interpreted as
22.0ºC)
•Fahrenheit value: Value in Modbus register is the temperature value in
Fahrenheit (i.e. a value “72” in the Modbus register must be interpreted as 72ºF
(~22ºC).
4.3 DIP-switch Configuration Interface
All the configuration values on DK-RC-MBS-1 can be written and read from Modbus interface.
Otherwise, some of them can also be setup from its on-board DIP-switch interface.
The device has DIP-switches SW1, SW3 and SW4 on the following locations:
SW3
SW4
IntesisBox®
DK-RC-MBS-1
EIA485
A+ B-
P1 P2
AC Unit
SW1
SW1
SW4
ON
1 2 3 4
ON
SW3
1 2 3 4
1 2 3 4 5 6 7 8
ON

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The following tables apply to the interface´s configuration through DIP-switches:
SW1 –AC indoor unit’s features
SW1-P1..4
Description
Slave - A Daikin BRC Controller must be present in P1P2 bus, configured as Master (Default value)
Master –Daikin BRC Controller not needed in P1P2 bus. If it exists, it must be configured as Slave
Master of Operation Mode (For VRV only) (Default value) 11
Slave of Operation Mode (For VRV only)
Reserved, not used (Default value)
Reserved, not used
Daikin Indoor Unit ambient temperature reading (Default value) 12
Daikin Remote Controller ambient temperature reading
Table 4.1 SW1: AC indoor unit´s features
SW3/SW4 –Baud rate configuration
SW3-P7..8
SW4-P3
Description
2400bps
4800bps
9600bps (Default value)
19200bps
38400bps
57600bps
76800bps
115200bps
Table 4.2 SW3-SW4: Modbus baud rate
11
Explanation in Section 8 of this document
12
From firmware version 1.2 onwards
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON

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SW4 –Degrees/Decidegrees (x10), temperature magnitude (ºC/ºF) and EIA-485 termination
resistor.
Table 4.3 SW4: Temperature and termination resistor configuration
SW4-P1..2-4
Description
Temperature values in Modbus register are represented in degrees (x1) (Default value)
Temperature values in Modbus register are represented in decidegrees (x10)
Temperature values in Modbus register are represented in Celsius degrees (Default value)
Temperature values in Modbus register are represented in Fahrenheit degrees
EIA-485 bus without termination resistor (Default value)
Internal termination resistor of 120Ω connected to EIA-485 bus
ON
ON
ON
ON
ON
ON

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SW3 –Modbus Slave address
Table 4.4 SW3: Modbus slave address
Add
SW3-P1..6
Add
SW3-P1..6
Add
SW3-P1..6
Add
SW3-P1..6
Add
SW3-P1..6
0
13
26
39
52
1
14
27
40
53
2
15
28
41
54
3
16
29
42
55
4
17
30
43
56
5
18
31
44
57
6
19
32
45
58
7
20
33
46
59
8
21
34
47
60
9
22
35
48
61
10
23
36
49
62
11
24
37
50
63
12
25
38
51
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON

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4.4 Implemented Functions
DK-RC-MBS-1 implements the following standard Modbus functions:
▪3: Read Holding Registers
▪4: Read Input Registers
▪6: Write Single Register
▪16: Write Multiple Registers (Despite this function is allowed, the interface does not
allow to write operations on more than 1 register with the same request, this means that
length field should be always be 1 when this function is being used in case of writing)
4.5 Device LED indicator
The device includes two LED indicators to show all the possible operational states. In the
following table there are written the indicators which can be performed and their meaning.
L1 (green LED)
Device status
LED indication
ON / OFF Period
Description
During not normal
operation
LED blinking
500ms ON / 500ms OFF
Communication error
During normal
operation
LED flashing
100ms ON / 1900ms OFF
Normal operation (configured and
working properly)
L2 (red LED)
Device status
LED indication
ON / OFF Period
Description
During not normal
operation
LED Pulse
3sec ON / --- OFF
Under voltage
L1 (green LED) & L2 (red LED)
Device status
LED indication
ON / OFF Period
Description
During normal
operation
LED Pulse
5sec ON / --- OFF
Device Start-up
During not normal
operation
LED alternatively
blinking
500ms ON / 500ms OFF
Flash checksum not OK

DK-RC-MBS-1
User’s Manual r3.3 EN
© Intesis Software S.L.U. - All rights reserved
This information is subject to change without notice
IntesisBox®is a registered trademark of Intesis Software SLU
URL
Email
Phone
http://www.intesisbox.com
[e-mail]
[phone]
16/23
4.6 EIA-485 bus. Termination resistors and Fail-Safe Biasing
mechanism
EIA-485 bus requires a 120Ω terminator resistor at each end of the bus to avoid signal
reflections.
In order to prevent fail status detected by the receivers, which are “listening”the bus, when all
the transmitters’outputs are in three-state (high impedance), it is also required a fail-safe
biasing mechanism. This mechanism provides a safe status (a correct voltage level) in the bus
when all the transmitters’ outputs are in three-state. This mechanism must be supplied by the
Modbus Master.
The DK-RC-MBS-1 device includes an on-board terminator resistor of 120Ω that can be
connected to the EIA-485 bus by using DIP-switch SW4.
Some Modbus RTU EIA-485 Master devices can provide also internal 120Ω terminator resistor
and/or fail-safe biasing mechanism (check the technical documentation of the Master device
connected to the EIA-485 network in each case).

DK-RC-MBS-1
User’s Manual r3.3 EN
© Intesis Software S.L.U. - All rights reserved
This information is subject to change without notice
IntesisBox®is a registered trademark of Intesis Software SLU
URL
Email
Phone
http://www.intesisbox.com
[e-mail]
[phone]
17/23
5. Electrical and Mechanical features
Enclosure
Plastic, type PC (UL 94 V-0)
Net dimensions (dxwxh):
93 x 53 x 58 mm / 3.7” x 2.1” x 2.3”
Color: Light Grey. RAL 7035
Operation
Temperature
0ºC to +60ºC
Weight
85 g.
Stock
Temperature
-20ºC to +85ºC
Mounting
Wall
DIN rail EN60715 TH35.
Operational
Humidity
<95% RH, non-condensing
Terminal Wiring
(for low-voltage
signals)
For terminal: solid wires or stranded wires
(twisted or with ferrule)
1 core: 0.5mm2… 2.5mm2
2 cores: 0.5mm2… 1.5mm2
3 cores: not permitted
Stock Humidity
<95% RH, non-condensing
Modbus RTU
port
1 x Serial EIA485 Plug-in screw terminal
block (2 poles):
A, B
Compatible with Modbus RTU EIA-485
networks
Isolation voltage
1500 VDC
AC unit port
1 x P1P2 bus Plug-in screw terminal block
(2 poles):
P1, P2
Compatible with Daikin networks
Isolation
resistance
1000 MΩ
Switch 1
(SW1)
1 x DIP-Switch for AC features
Protection
IP20 (IEC60529)
Switch 3
(SW3)
1 x DIP-Switch for Modbus RTU settings
LED indicators
2 x Onboard LED - Operational
status
Switch 4
(SW4)
1 x DIP-Switch for extra functions
EIA-485
Port
AC Unit
connection
DIP
Switch SW3
DIP
Switch SW1
LED
Indicators
DIP
Switch SW4

DK-RC-MBS-1
User’s Manual r3.3 EN
© Intesis Software S.L.U. - All rights reserved
This information is subject to change without notice
IntesisBox®is a registered trademark of Intesis Software SLU
URL
Email
Phone
http://www.intesisbox.com
[e-mail]
[phone]
18/23
6. List of supported AC Unit Types.
A list of Daikin indoor unit model’s references compatible with DK-RC-MBS-1 and its available
features can be found on this link:
https://www.intesisbox.com/intesis/support/compatibilities/IntesisBox_DK-RC-xxx-1_AC_Compatibility.pdf

DK-RC-MBS-1
User’s Manual r3.3 EN
© Intesis Software S.L.U. - All rights reserved
This information is subject to change without notice
IntesisBox®is a registered trademark of Intesis Software SLU
URL
Email
Phone
http://www.intesisbox.com
[e-mail]
[phone]
19/23
7. Error Codes
Error Code
Modbus
Error in
Remote
Controller
Error
category
Error Description
0
N/A
DK-RC-MBS-1
No active error
17
A0
External protection devices activated
18
A1
Indoor unit PCB assembly failure
19
A2
Interlock error for fan
20
A3
Drain level system error
21
A4
Temperature of heat exchanger (1) error
22
A5
Temperature of heat exchanger (2) error
23
A6
Fan motor locked, overload, over current
24
A7
Swing flap motor error
25
A8
Overcurrent of AC input
26
A9
Electronic expansion valve drive error
27
AA
Heater overheat
28
AH
Dust collector error / No-maintenance filter error
30
AJ
Indoor
Capacity setting error (indoor)
31
AE
Unit
Shortage of water supply
32
AF
Malfunctions of a humidifier system (water leaking)
33
C0
Malfunctions in a sensor system
36
C3
Sensor system of drain water error
37
C4
Heat exchanger (1) (Liquid pipe) thermistor system
error
38
C5
Heat exchanger (1) (Gas pipe) thermistor system error
39
C6
Sensor system error of fan motor locked, overload
40
C7
Sensor system of swing flag motor error
41
C8
Sensor system of over-current of AC input
42
C9
Suction air thermistor error
43
CA
Discharge air thermistor system error
44
CH
Contamination sensor error
45
CC
Humidity sensor error
46
CJ
Remote control thermistor error
47
CE
Radiation sensor error
48
CF
High pressure switch sensor
49
E0
Protection devices activated
50
E1
Outdoor unit PCB assembly failure
52
E3
High pressure switch (HPS) activated
53
E4
Low pressure switch (LPS) activated
54
E5
Overload of inverter compressor motor
55
E6
Over current of STD compressor motor
56
E7
Overload of fan motor / Over current of fan motor
57
E8
Over current of AC input
58
E9
Electronic expansion valve drive error
59
EA
Four-way valve error
60
EH
Pump motor over current
61
EC
Outdoor
Water temperature abnormal
62
EJ
Unit
(Site installed) Protection device activated
63
EE
Malfunctions in a drain water
64
EF
Ice thermal storage unit error
65
H0
Malfunctions in a sensor system
66
H1
Air temperature thermistor error
67
H2
Sensor system of power supply error
68
H3
High Pressure switch is faulty
69
H4
Low pressure switch is faulty
70
H5
Compressor motor overload sensor is abnormal

DK-RC-MBS-1
User’s Manual r3.3 EN
© Intesis Software S.L.U. - All rights reserved
This information is subject to change without notice
IntesisBox®is a registered trademark of Intesis Software SLU
URL
Email
Phone
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[e-mail]
[phone]
20/23
71
H6
Compressor motor over current sensor is abnormal
72
H7
Overload or over current sensor of fan motor is
abnormal
73
H8
Sensor system of over-current of AC input
74
H9
Outdoor air thermistor system error
75
HA
Discharge air thermistor system error
76
HH
Pump motor sensor system of over current is abnormal
77
HC
Water temperature sensor system error
79
HE
Sensor system of drain water is abnormal
80
HF
Ice thermal storage unit error (alarm)
81
F0
No.1 and No.2 common protection device operates.
82
F1
No.1 protection device operates.
83
F2
No.2 protection device operates
84
F3
Discharge pipe temperature is abnormal
87
F6
Temperature of heat exchanger(1) abnormal
91
FA
Discharge pressure abnormal
92
FH
Oil temperature is abnormally high
93
FC
Suction pressure abnormal
95
FE
Oil pressure abnormal
96
FF
Oil level abnormal
97
J0
Sensor system error of refrigerant temperature
98
J1
Pressure sensor error
99
J2
Current sensor error
100
J3
Discharge pipe thermistor system error
101
J4
Low pressure equivalent saturated temperature sensor
system error
102
J5
Outdoor
Suction pipe thermistor system error
103
J6
Unit
Heat exchanger(1) thermistor system error
104
J7
Heat exchanger(2) thermistor system error
105
J8
Oil equalizer pipe or liquid pipe thermistor system error
106
J9
Double tube heat exchanger outlet or gas pipe
thermistor system error
107
JA
Discharge pipe pressure sensor error
108
JH
Oil temperature sensor error
109
JC
Suction pipe pressure sensor error
111
JE
Oil pressure sensor error
112
JF
Oil level sensor error
113
L0
Inverter system error
116
L3
Temperature rise in a switch box
117
L4
Radiation fin (power transistor) temperature is too high
118
L5
Compressor motor grounded or short circuit, inverter
PCB fault
119
L6
Compressor motor grounded or short circuit
120
L7
Over current of all inputs
121
L8
Compressor over current, compressor motor wire cut
122
L9
Stall prevention error (start-up error) Compressor
locked, etc.
123
LA
Power transistor error
125
LC
Communication error between inverter and outdoor
control unit
129
P0
Shortage of refrigerant (thermal storage unit)
130
P1
Power voltage imbalance, open phase
132
P3
Sensor error of temperature rise in a switch box
133
P4
Radiation fin temperature sensor error
134
P5
DC current sensor system error
135
P6
AC or DC output current sensor system error
136
P7
Total input current sensor error