Installation Guide
6 configurations
2 configurations
1 configuration
communication
Controller solution
monitoring unit
Gas Detection Unit (GDU)
GDA, GDC, GDHC, GDHF, GDH
Technician use only!
This unit must be installed by a suitably qualified technican who
148R9631
will install this unit in accordance with these instructions and the
standards set down in their particular industry/country.
Info for UK customers only:
Danfoss Ltd.
Oxford Road, UB9
4LH Denham, UK
ENGLISH
Please observe that a Danfoss GDU works as a safety device
securing a reaction to a detected high gas concentration. If a
leakage occur, the GDU will provide alarm functions, but it will
not solve or take care of the leakage root cause itself.
148R9631
Suitably qualified operators of the unit should be aware of the
regulations and standards set down by their industry/country for
the operation of this unit.
These notes are only intended as a guide and the manufacturer
bears no responsibility for the installation or operation of this unit.
Failure to install and operate the unit in accordance with these
instructions and with industry guidelines may cause serious injury
including death and the manufacturer will not be held responsible
in this regard.
It is the installer’s responsibility to adequately ensure that the
equipment is installed correctly and set up accordingly based on
the environment and the application in which the products are
being used.
Configurations and Wiring: All 3 types of Gas Detection Units (GDU)
Annual Test
To comply with the requirements of EN378 and the F GAS
regulation sensors must be tested annually. Danfoss GDU's are
provided with a test button that should be activated once a year
for testing of the alarm reactions.
Additional the sensors must be tested for functionality by either
Bump test or Calibration. Local regulations should always be
followed
After exposure to a substantial gas leak, sensor should be checked
and replaced if necessary.
Check local regulations on calibration or testing requirements.
Service tools
Gas Detection Controller
Option: Modbus
Option: UPS
Max. 96 sensors
Wire break
Premium
Basic +
Basic
Sensor
Sensor
Basic GDU
Buzzer and light
3-color-alarm
1
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Premium+
Buzzer and light
3-color-alarm
Premium Flex
Premium GDU (Controller)
Premium Remote
5 meter
remote sensor
Premium Duplex
Sensor 2
Premium Uptime
Display
UPS
Service Tool
Handheld
Danfoss Pen
for Heavy
Heavy Duty
Sensor
Heavy Duty GDU
Duty display
AN272542819474en-000201 | 1
oss
Relays 1 and 2 de-energized (default)
Relay 3 energized (default)
Danfoss Basic GDU
12 4
Bus_B
Bus_A
0 V AC/DC
24 V AC/DC
Ackn. -/Test
button T1
X4
3
4
X8
X2
5
X9
Service Tool
Buzzer &
3-light alarm
X1
Analog Output
Status LED
Green/Yellow/Red
GND
JP5*
Open: 4-20mA
Closed: 2-10V AO_01
Jumper
J1
J2
J3
Sensor
Danfoss
148H119_11-2018
Status LED:
GREEN is power on.
YELLOW is an indicator of Error.
- when the sensor head is disconnected or
not the expected type
- AO is activated but nothing connected
- flashing when sensor is in special mode
(e.g. when changing parameters)
RED on alarm, similar to the Buzzer & light
alarm.
Ackn. -/Test button:
TEST - The button must be pressed
for 20 sec.
- Alarm1 and Alarm2 is simulated, stop
on release
ACKN. - Pressed while Alarm2, the audible
warning switches off and goes back on after
5 min. when the alarm situation is still active.
* JP5 open → AO 4 – 20 mA (Default)
JP5 closed → AO 2 – 10 Volt
NOTE:
A resistor comes installed on the analog
output connections – if analog output
is used, remove the resistor.
2
Danfoss Premium GDU
Power 24 V DC
23
GND
24 V DC
Ackn./Test
button
Power Bus Comm.
2
3
1
X11
DI_1
DI_2
GND
Digital
Input
Buzzer &
3-light alarm
3
1
X1
NC
Local
Bus_1
Sensor
in operating mode at No alarm.
Configurable
Relay 1
Alarm 1
3
2
1
Status LED
Green/Yellow/Red
Relay status
LED Green
Service Tool
Bus_A
Field
Bus
321
Bus_B
Analog
Output
JP2*
AO_01
X12
in operating mode at No alarm.
Relay 2
Alarm 2
3
132
X2
Relays shown de-energized
open: 4-20mA
closed: 2-10 V
4
GND
2
Relay status
LED Green
X3
Local
Bus_2
Ackn.
Button
Sensor
Configurable
Relay 3
Error
Relay status
LED Green
Digital
Output
NC
567
4
X13
GND
1
Horn
X4
Flash light
Status LED:
GREEN is power on.
YELLOW is an indicator of Error.
- when the sensor head is disconnected or
not the expected type
- AO is activated but nothing connected
RED on alarm, similar to the Buzzer & light
alarm.
Ackn. -/Test button:
TEST - The button must be pressed
for 20 sec.
- Alarm1 and Alarm2 is simulated, stop
on release
ACKN. - Pressed while Alarm2, the audible
warning switches off and goes back on after
5 min. when the alarm situation is still active.
* JP2 open → AO 4 – 20 mA (Default)
JP2 closed → AO 2 – 10 Volt
NOTE:
A resistor comes installed on the analog
Danfoss
148H120_01-2018
output connections – if analog output
is used, remove the resistor.
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Sensor PX2
Danf
148H122_11-2018
NPT ¾ in.
Danfoss
148H121_01-2018
Danfoss Premium Uptime GDU
Power supply
Relay 1
Relay 2
Relay 3
12
0.8 Ah
12
0.8 Ah
Danf
148H147_02-2018
24 V DC
V
V
321321
24 V DC
GND
X1
ACCU
ACCU
4
Danfoss Heavy Duty GDU (ATEX, IECEx approved)
AR 01
AR 02
X2 X3 X4
NPT ¾”(ANSI B1.20.1)
Internal Thread
132 321
AR 03
90 - 240 V AC
V+ V- PE N
Power supply
90 - 240 V AC
L
24 V DC, 15 VA
oss
1
+24 V DC
2 +24 V DC
3
GND
4
BUS_A
56BUS_B
4 - 20 mA output
Service
Tool
LED
Status
Ackn. Button
Sensor
head
On board LED is similar to the display LED:
Green is power on
7
8
9
10
11
oss
Fault relais energized in
operating mode at No alarm
- Default
Alarm relais de-energized in
operating mode at No alarm
- Default (Configurable)
NPT ¾”(ANSI B1.20.1)
Internal Thread
Sensor
Yellow is an indicator of Error
- when the sensor head is disconnected or not
the expected type
- AO is activated but nothing connected
RED on alarm
On board Ackn. -/Test button:
Test: The button must be pressed
for 20 sec.
- Alarm is simulated, stop on release
Ackn.: Pressed while Alarm2, the audible
warning switches off and goes back on after
5 min. when the alarm situation is still active
(also possible over ESC button (use the
5
Location of Sensors
Gas type Relative density (Air = 1) Recommended sensor location
R717 Ammonia <1 Ceiling
R744 CO >1 Floor
R134a >1 Floor
R123 >1 Floor
R404A >1 Floor
R507 >1 Floor
R290 Propane >1 Floor
magnetic Pen).
6
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GDU Addr. 05 GDU Addr. 04
Danf
148H124_1
Gas Detection Controller: Fieldbus wiring - max 96 sensors in total i.e. up to 96 GDU (Basic, Premium and/or Heavy Duty)
WRONG
Wire length max. 900 meter (2953 ft) per segment.
More segments with additional expansion modules max. 7200 meter (23622 ft).
Additional power limitations must be calculated.
R
Controller
unit
= Terminating resistor 560 OhmR
= GDU (Basic, Premium and/or Heavy Duty)
R
Controller
unit
7
Check of loop completion. Example: 5 x Basic in return loop
R
R
RIGHT
Danfoss
148H123_03-2018
Controller Unit
0 V DC
24 V DC
BUS_B
BUS_A
0 V DC
24 V DC
Ohm
560 R
+
(DC)
4
3
2
1
GDU Addr. 01 GDU Addr. 02 GDU Addr. 03
4
3
2
1
V
4
3
2
1
+
V
(DC)
4
3
2
1
Heavy Duty GDU: U
Other GDU: U
4
3
2
1
= 16 V DC
min
= 20 V DC
min
oss
Check of loop resistance: See section: Controller unit multiple GDU commissioning 2. NOTE: Remember to disconnect the wire from the board during measuring.
Check of power polarity: See section: Controller unit multiple GDU commissioning 3.
Check of BUS polarity: See section: Controller unit multiple GDU commissioning 3.
Individual Addresses for the GDU's are given at commisioning, see Controller Unit multiple GDU's commisioning, according to a predetermined "BUS address plan"
8
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Attachment of suspension ears (Basic and Premium)
Danfoss
Danfoss
70
115
9
Cable Gland opening
148H125_01-2018
148H126_01-2018
Hole punching for Cable gland:
1. Select the location for the safest cable entry.
2. Use a sharp screwdriver and a small hammer.
3. Place the screwdriver and hammer with precision
while moving the screwdriver within a small area
until the plastic is penetrated.
Continue precision punching with small movements
until the round piece can be pulled out by your
fingers.
Remove potential burrs and secure flat surfaces.
Install the Cable gland according to the enclosed guide.
10
Ambient conditions :
Please observe the ambient conditions specified for each specific GDU, as stated on the product. Do not install the units outside
the given temperature and humidity range.
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ENGLISH
General GDU Mounting / Electrical wiring
• All GDU's are for wall mounting
• Supporting ears are installed like shown in fig. 9
• Cable entry is recommended on box side. See fig. 10
• Sensor position downwards
• Observe possible constructors instruction
• Leave the red protection cap (seal) on the sensor head until
commisioning
When choosing the mounting site please pay attention to the following:
• The mounting height depends on the relative density of the gas type to
be monitored, see fig 6.
• Choose mounting location of the sensor according to the local
regulations
• Consider ventilation conditions. Do not mount the sensor close to
airflow (air passages, ducts etc.)
• Mount the sensor at a location with minimum vibration and minimum
temperature variation (avoid direct sunlight)
• Avoid locations where water, oil etc. may influence proper operation and
where mechanical damage might be possible
• Provide adequate space around the sensor for maintenance and
calibration work.
Wiring
The technical requirements and regulations for wiring, electrical security,
as well as project specific and environmental conditions etc. must be
observed when mounting.
We recommend the following cable types¹
• Power supply for controller 230V at least
NYM-J 3 x 1.5 mm
• Alarm message 230 V (also possible together with power supply)
NYM-J X x 1.5 mm
• Signal message, bus connection to Controller Unit, warning devices 24 V
J-Y(St)Y 2x2 x 0.8
• Possibly connected external analog transmitters
J-Y(St)Y 2x2 x 0.8
• Cable for Heavy Duty: 7 - 12 mm diameter round cable
¹ The recommendation does not consider local conditions such as fire protection etc.
The alarm signals are available as potential-free change-over contacts. If
required the voltage supply is available at the power terminals.
The exact position of the terminals for the sensors and alarm relays is
shown in the connection diagrams (see figures 3 and 4).
Basic GDU
The Basic GDU is designed for the connection of 1 sensor via local bus.
The GDU provides the power supply of the sensor and makes the
measured data available for digital communication. Communication
with the Controller Unit takes place via the RS 485 fieldbus interface
with Controller Unit protocol. Other communication protocols for direct
connection to superordinate BMS are available as well as Analog Output
4-20 mA.
The sensor is connected to the local bus via a plug connection enabling
simple sensor exchange instead of an on-site calibration. The internal
X-Change routine recognizes the exchanging process and the exchanged
sensor and starts the measurement mode automatically.
The internal X-change routine examines the sensor for actual type of
gas and actual measuring range. If data does not match the existing
configuration, the build in status LED indicates an error. If everything is OK
the LED will light up green.
For convenient commissioning, the GDU is pre-configured and
parameterized with factory-set defaults.
As an alternative, the on-site calibration via the Controller Unit Service Tool
can be performed with the integrated, userfiendly calibration routine.
For Basic units with Buzzer & Light, alarms will be given according to
following table:
Digital outputs
Action Reaction
Gas signal < alarm threshold 1 OFF GREEN
Gas signal > alarm threshold 1 OFF RED Slow blinking
Gas signal > alarm threshold 2 ON RED Fast blinking
Gas signal ≥ alarm threshold 2,
but ackn. button pressed
Gas signal < (alarm threshold 2 - hysteresis)
but >= alarm threshold 1
Gas signal < (alarm threshold 1 - hysteresis)
but not acknowledged
No alarm, no fault OFF GREEN
No fault, but maintenance due OFF GREEN Slow blinking
Communication error OFF YELLOW
Alarm thresholds can have the same value, therefore the relays and/or Buzzer and LED
can be triggered simultaniously.
Horn
OFF after
delay ON
OFF RED Slow blinking
OFF RED Very fast blinking
Reaction
LED
RED Fast blinking
Premium GDU (Controller)
The Premium GDU is designed for the connection of max. two sensors
via local bus. The controller monitors the measured values and activates
the alarm relays if the set alarm thresholds for pre-alarm and main alert
are exceeded. In addition, the values are provided for direct connection
to the monitoring system (Controller Unit) via an RS-485 interface. Other
communication protocols for direct connection to superordinate BMS are
available as well as Analog Output 4-20 mA.
The SIL 2 compliant self-monitoring function in the Premium GDU and in
the connected sensor activates the error message in case of an internal
error as well as in case of an error in the local bus communication.
The sensor is connected to the local bus via a plug connection enabling
simple sensor exchange instead of an on-site calibration. The internal
X-Change routine recognizes the exchanging process and the exchanged
sensor and starts the measurement mode automatically.
The internal X-change routine examines the sensor for actual type of
gas and actual measuring range and if data does not match the existing
configuration, the build in status LED indicates an error. If everything is OK
the LED will light up green.
For convenient commissioning, the GDU is pre-configured and
parameterized with factory-set defaults.
As an alternative, the on-site calibration via the Controller Unit Service Tool
can be performed with the integrated, userfriendly calibration routine.
Digital outputs with three relays
Action Reaction Reaction Reaction Reaction Reaction Reaction
Gas signal < alarm threshold 1 OFF OFF OFF OFF ON GREEN
Gas signal > alarm threshold 1 ON OFF OFF OFF ON RED Slow
Gas signal > alarm threshold 2 ON ON ON ON ON RED Fast
Gas signal ≥ alarm threshold 2,
but ackn. button pressed
Gas signal < (alarm threshold
2 - hysteresis) but >= alarm
threshold 1
Gas signal < (alarm threshold
1 - hysteresis) but not
acknowledged
No alarm, no fault OFF OFF OFF OFF ON GREEN
No fault, but maintenance due OFF OFF OFF OFF ON GREEN Slow
Communication error OFF OFF OFF OFF OFF YELLOW
Note 1:
Status OFF = Relay is configured “Alarm ON = Relay“ or the Premium Multi-SensorController is free from tension.
Note 2:
Alarm thresholds can have the same value, therefore the relays and/or the horn and
flashlight can be triggered together.
Relay Mode
Definition of the relay operation mode. The terms energized / de-energized
come from the terms energized / de- energized to trip principle (opencircuit / closed circuit principle) used for safety circuits. The terms refer
to the activation of the relay coil, not to the relay contacts (as they are
executed as a changeover contact and available in both principles).
The LEDs attached to the modules show the two states in analogy (LED off
-> relay de-energized)
Relay 1
(Alarm1)
ON ON ON OFF after
ON OFF OFF OFF ON RED Slow
OFF OFF OFF OFF ON RED Very
Relay 2
(Alarm2)
Flashlight
X13-7
Horn X13-6 Relay 3
delay ON
(Fault)
LED
blinking
blinking
RED Fast
blinking
blinking
fast blinking
blinking
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ENGLISH
Heavy Duty GDU
Approved according to ATEX and IECEx for zones 1 and 2.
Permitted ambient temperature range: -40 °C < Ta < +60 °C
Marking:
Ex Symbol and
II 2G Ex db IIC T4 Gb CE 0539
Certification:
BVS 18 ATEX E 052 X
IECEx BVS 18.0044X
The Heavy Duty GDU is designed for the connection of 1 sensor via local bus.
The GDU provides the power supply of the sensor and makes the
measured data available for digital communication. Communication
with the Controller Unit takes place via the RS 485 fieldbus interface
with Controller Unit protocol. Other communication protocols for direct
connection to superordinate BMS are available as well as Analog Output
4-20 mA.
The sensor is connected to the local bus via a plug connection enabling
simple sensor exchange instead of an on-site calibration. The internal
X-Change routine recognizes the exchanging process and the exchanged
sensor and starts the measurement mode automatically.
The internal X-change routine examines the sensor for actual type of
gas and actual measuring range. If data does not match the existing
configuration, the build in status LED indicates an error. If everything is OK
the LED will light up green.
For convenient commissioning, the GDU is pre-configured and
parameterized with factory-set defaults.
As an alternative, the on-site calibration via the Controller Unit Service Tool
can be performed with the integrated, userfriendly calibration routine.
Installation Work
Assembly work must only be carried out under gas-free
conditions. The housing must neither be drilled nor be
drilled through.
The orientation of the GDU should always be horizontal,
with the sensor head pointing downwards.
The mounting is done without opening the housing by
using the two holes (D = 8 mm) of the fastening strap with
suitable screws.
The Heavy duty GDU must only be opened under gas-free
and voltage-free conditions.
The enclosed cable gland has to be checked for
admissibility for the requested requirements before
installation in position “Entry 3”. If the Heavy duty
GDU is supplied without cable gland, a special cable
gland approved for Ex protection class EX d and for the
requirements of the application has to be mounted there.
When inserting the cables you have to strictly follow the
instructions enclosed to the cable glands.
No insulating sealing material must be poured into the NPT
¾ “threads of the cable gland and blanking plugs because
the potential equalization between housing and cable
gland / blind plugs is via the thread.
The cable gland must be tightened firmly with a suitable
tool to torque 15 Nm. Only when doing so you can ensure
the required tightness.
After completion of work, the GDU must be closed again.
The cover has to be completely screwed in and secured
with the locking screw against inadvertent loosening.
General Notes
• The terminals of the Heavy duty GDU are located behind the display.
• Only a professional should perform the wiring and the connection of
the electrical installation according to the wiring diagram in compliance
with the relevant regulations and only when de-energized!
• When connecting cables and conductors, please observe minimum
length of 3 m according to EN 60079-14.
• Connect the housing to the equipotential bonding via the external
ground terminal.
• All terminals are Ex e type with spring contact and push actuation. The
permissible conductor cross section is 0.2 to 2.5 mm² for single wires
and multi-wire cables.
• Use cables with a braided shield for compliance with the interference
immunity. The shield must be connected to the inside connection of the
housing with a maximum length of about 35 mm.
• For the recommended cable types, cross sections and lengths please
refer to the table below.
• To comply with the requirements of servicing or operating the device
without opening it (EN 60079-29- 1 4.2.5) it is possible to calibrate or
operate the device remotely via the central bus. For this it is necessary
to lead the central bus out to the safe area via a cable.
Further Notes and Restrictions
The maximum operating voltage and the terminal voltage of the relays
have to be limited to 30 V by adequate measures.
The maximum switching current of the two relay contacts should be
limited to 1 A by appropriate external measures.
Repairs to flameproof joints are not intended and lead to the immediate
loss of the type approval for the pressure-resistant casing.
Cross-section
(mm²)
With P, freon sensor heads
Operat ing voltage with
4-20 mA signal
Operat ing voltage with
central bus²
Operat ing voltage with
4-20 mA signal
Operat ing voltage with
central bus²
¹ The max. cable lengths and our recommendation don’t consider any local conditions, like fire
protection, national regulations etc.
² For the central bus we recommend using the cable JE-LiYCY 2x2x0.8 BD or 4 x2x0.8 BD.
0.5 250
1.0 500
0.5 300
1.0 70 0
With SC , EC sensor heads
0.5 400
1.0 800
0.5 600
1.0 900
Max. le ngth for 24 V DC¹
(m)
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ENGLISH
Commissioning
For sensors that can be poisoned by e.g. silicones like all semiconductor
and catalytic bead sensors, it is imperative to remove the protective (seal)
cap supplied only after all silicones are dry, and then energize the device.
For fast and comfortable commissioning we recommend proceeding as
follows. For digital devices with self-monitoring all internal errors are
visible via the LED. All other error sources often have their origins in the
field, because it is here where most of the causes for problems in the field
bus communication appear.
Optical Check
• Right cable type used.
• Correct mounting height according to definition in Mounting.
• Led status
Comparing sensor gas type with GDU default settings
Each sensor ordered is specific and must match the GDU default settings.
The GDU software automatically reads the specification of the connected
sensor and compares with the GDU settings.
If other gas sensor types are connected, you have to adjust them with the
configuration tool, because otherwise the device will respond with an
error message.
This feature increases the user and operating security.
New sensors are always delivered factory-calibrated by Danfoss. This is
documented by the calibration label indicating date and calibration gas. A
repeated calibration is not necessary during commissioning if the device is
still in its original packaging (air-tight protection by the red protective cap)
and the calibration doesn’t date back more than 12 months.
Functional test (for initial operation and maintenance)
The functional test should be carried out during each service, but at least
once a year.
Functional test is done by pressing the test button for more than 20
sec and observing all connected outputs (Buzzer, LED, Relay connected
devices) working properly. After deactivation all outputs must
automatically return to its initial position
Zero-point test with fresh outdoor air
Zero-point test with fresh outdoor air. (If prescribed by local regulations)
A potential zero offset can be read out by use of the Service tool.
Trip test with reference gas (If prescribed by local regulations)
The sensor is gassed with reference gas (for this you need a gas bottle with
pressure regulator and a calibration adapter).
In doing so, the set alarm thresholds are exceeded, and all output
functions are activated. It is necessary to check if the connected output
functions are working correctly (e.g. the horn sounds, the fan switches on,
devices shut down). By pressing the push-button on the horn, the horn
acknowledgment must be checked. After removal of the reference gas, all
outputs must automatically return to its initial position.
Other than the simple functional testing, it is also possible to perform a
functional test by means of calibration. For further information, please
refer to the User Manual.
Controller Unit multiple GDU commisioning
For fast and comfortable commissioning we recommend proceeding as
follows. Especially the given specifications of the field bus cable have
to be checked carefully, because it is here where most of the causes for
problems in the field bus communication appear.
1. Optical Check
• Right cable type used (JY(St)Y 2x2x0.8LG or better).
• Cable topology and cable length.
• Correct mounting height of the sensors
• Correct connection at each GDU according to fig. 8
• Termination with 560 ohm at the beginning and at the end of each
segment.
• Pay special attention so that the polarities of BUS_A and BUS_B are not
reversed!
2. Check Short-circuit / Interruption / Cable Length of the Field Bus
(see fig. 8.1)
This procedure has to be executed for each single segment.
The field bus cable must be laid at the connector terminal block of the GDU
for this testing. The plug, however, is not yet plugged into the GDU.
Disconnect the field bus leads from the Controller Unit central control.
Connect ohmmeter to the loose leads and measure the total loop
resistance. See fig. 8.1 The total loop resistance is calculated as follows:
• R (total) = R (cable) + 560 Ohm (terminating resistance)
• R (cable) = 72 Ohm / km (loop resistance) (cable type JY(St)Y 2x2x0.8LG)
R (total) (ohm) Cause Troubleshooting
< 560 Short-circuit Look for sh ort-circuit i n the
infinite Open -circuit Loo k for interrupti on in the
> 560 < 640 Cable is o. k. --
field bus c able.
field bus c able.
The allowed cable length can be calculated in a sufficiently exact way
according to the following formula.
Total cable length (km) = (R (total) – 560 Ohm) / 72 Ohm
If the field bus cable is OK, reconnect it to the central unit.
3. Check Voltage and Bus Polarity of the Field Bus (see fig. 8.2 and 8.3)
• Bus connector to be plugged into each GDU.
• Switch operating voltage on at the Controller Unit central unit.
• The green LED at the GDU lights up weakly when operating voltage is
applied (voltage indicator).
• Check operating voltage and bus polarity at each GDU according to fig.
7.1 and 7.2. U
= 16 V DC (20 V DC for Heavy Duty)
min
• Bus polarity:
Measure tension BUS_A against 0 V DC and BUS_B against 0 V DC. U
BUS_A = ca. 0.5 V > U BUS_B
U BUS_B = ca. 2 – 4 V DC (depending on the number of GDU and on the
cable length)
4. Addressing of the GDU
After having checked the field bus successfully, you have to assign a basic
communication address to each GDU via the display on the unit, the
service tool or the PC tool. With this basic address, the data of the Sensor
Cartridge assigned to input 1 are sent via the field bus to the gas controller.
Any further sensor connected / registered on the GDU automatically gets
the next address.
Choose the menu Address and enter the predetermined Address according
to the Bus Address Plan.
If this connection is OK, you can read the current GDU address in the menu
“Address“ either at the display on the unit or by plugging in the service tool
or the PC tool.
0 = Address of new GDU
XX = Current GDU address (permissible address range 1 – 96)
The detailed description of the addressing can be taken from the user
manual of the Controller unit or the Controller unit service tool.
© Danfoss | Climate solutions | 2021.06
Further documentation:
AN272542819474en-000201 | 8
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