Bender ISOMETER isoHV425 User manual

Manual EN
ISOMETER® isoHV425 with AGH422
Insulation monitoring device with coupling device
for unearthed AC, AC/DC and DC systems up to 3(N AC, AC 1000 V
Software version: D0453 V1.xx (isoHV425-D4-4 / D0500 V1.xx (isoHV425-D4M-4
isoHV425_D00082_06_M_XXEN/07.2023

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ISOMETER® isoHV425 with AGH422
Table of contents
1Gene al info mation...........................................................................................5
1.1 How to use this manual................................................................................................................................5
1.2 Indication of important instructions and information.......................................................................5
1.3 Signs and symbols...........................................................................................................................................5
1.4 Service and Support....................................................................................................................................... 5
1.5 Training courses and seminars...................................................................................................................5
1.6 Delivery conditions......................................................................................................................................... 6
1.7 Inspection, transport and storage.............................................................................................................6
1.8 Warranty and liability.....................................................................................................................................6
1.9 Disposal of Bender devices..........................................................................................................................6
1.10 Safety.................................................................................................................................................................... 7
2Function...............................................................................................................8
2.1 Intended use......................................................................................................................................................8
2.2 Device features................................................................................................................................................. 8
2.3 Functional description...................................................................................................................................9
2.3.1 Monitoring the insulation resistance....................................................................................................... 9
2.3.2 Undervoltage/overvoltage monitoring................................................................................................ 10
2.3.3 Self test / error codes...................................................................................................................................10
2.3.4 Alarm assignment of the alarm relays K1/K2..................................................................................... 12
2.3.5 Measuring and response times................................................................................................................12
2.3.6 Password protection (on, OFF ................................................................................................................ 13
2.3.7 External test/reset button (T/R ............................................................................................................... 13
2.3.8 Fault memory..................................................................................................................................................13
2.3.9 History memory HiS..................................................................................................................................... 13
2.3.10 Digital interfaces (isoHV425-D4-4 ..........................................................................................................14
2.3.11 Analogue interface (isoHV425-D4M-4 ................................................................................................. 14
3Installation, connection and commissioning.................................................15
3.1 Dimensions...................................................................................................................................................... 15
3.2 Installation........................................................................................................................................................15
3.3 Connection.......................................................................................................................................................16
3.4 Commissioning...............................................................................................................................................19
4Ope ation.......................................................................................................... 20
4.1 Operating and display elements.............................................................................................................20
isoHV425_D00082_06_M_XXEN/07.2023 3

Table of contents
4.2 Menu overview...............................................................................................................................................22
4.3 Displaying measured values..................................................................................................................... 22
4.4 Setting the response values (AL ............................................................................................................ 23
4.4.1 Setting the response values for insulation monitoring.................................................................. 23
4.4.2 Setting the response values for undervoltage and overvoltage.................................................24
4.4.3 Response values overview.........................................................................................................................24
4.5 Configuring fault memory, alarm relays, and interfaces (out ......................................................24
4.5.1 Configuring the relays.................................................................................................................................24
4.5.2 Assigning the alarm messages to the relays...................................................................................... 24
4.5.3 Activating or deactivating fault memory.............................................................................................25
4.5.4 Configuring interface (isoHV425-D4-4 .................................................................................................26
4.5.5 Configuring analogue output (isoHV425-D4M-4 .............................................................................26
4.6 Setting delay times and self test cycles (t .......................................................................................... 26
4.7 Setting device control parameters (SEt ...............................................................................................27
4.8 Reset to factory settings.............................................................................................................................27
4.9 Showing and deleting the history memory........................................................................................27
4.10 Querying software version (InF .............................................................................................................. 28
5Data access via RS-485 inte face.....................................................................29
5.1 Data access using the BMS protocol..................................................................................................... 29
5.2 Data access using the Modbus RTU protocol.................................................................................... 29
5.2.1 Reading out the Modbus register from the ISOMETER®.................................................................29
5.2.2 Writing the Modbus register (parameter setting .............................................................................30
5.2.3 Exception code...............................................................................................................................................31
5.3 Modbus register assignment.................................................................................................................... 32
5.3.1 Modbus measured value registers......................................................................................................... 32
5.3.2 Modbus parameter register...................................................................................................................... 35
5.4 IsoData data string....................................................................................................................................... 39
6Technical data...................................................................................................40
6.1 Technical data isoHV425............................................................................................................................ 40
6.2 Technical data AGH422...............................................................................................................................44
6.3 Connection (for ISOMETER® and AGH ..................................................................................................46
6.4 Standards and certifications..................................................................................................................... 46
6.5 Ordering data..................................................................................................................................................47
6.6 Change log.......................................................................................................................................................48
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ISOMETER® isoHV425 with AGH422
1 Gene al info mation
1.1 How to use this manual
ADVICE
This manual is intended for qualified personnel working in electrical engineering and electronics!
Part of the device documentation in addition to this manual is the enclosed supplement " Safety
instructions for Bender products".
ADVICE
Read the operating manual before mounting, connecting and commissioning the device. Keep the
manual within easy reach for future reference.
1.2 Indication of impo tant inst uctions and info mation
DANGER
Indicates a high risk of danger that will result in death or serious injury if not avoided.
WARNING
Indicates a medium risk of danger that can lead to death or serious injury if not avoided.
CAUTION
Indicates a low-level risk that can result in minor or moderate injury or damage to property if not
avoided.
Information can help to optimise the use of the product.
1.3 Signs and symbols
Disposal Protect from moisture Protect from dust
Temperature range Recycling RoHS directives
1.4 Se vice and Suppo t
Information and contact details about customer service, repair service or field service for Bender devices are
available on the following website: Fast assistance | Bender GmbH & Co. KG.
1.5 T aining cou ses and semina s
Regular face-to-face or online seminars for customers and other interested parties:
www.bender.de > know-how > seminars.
isoHV425_D00082_06_M_XXEN/07.2023 5

General information
1.6 Delive y conditions
The conditions of sale and delivery set out by Bender GmbH & Co. KG apply. These can be obtained in printed
or electronic format.
The following applies to software products:
Die Elektroindustrie
‘Software clause in respect of the licensing of standard software as part of deliveries,
modifications and changes to general delivery conditions for products and services in the
electrical industry’
1.7 Inspection, t anspo t and sto age
Check the shipping and device packaging for transport damage and scope of delivery. In the event of
complaints, the company must be notified immediately, see "www.bender.de > service & support.".
The following must be observed when storing the devices:
1.8 Wa anty and liability
Warranty and liability claims for personal injury and property damage are excluded in the case of:
•Improper use of the device.
•Incorrect mounting, commissioning, operation and maintenance of the device.
•Failure to observe the instructions in this operating manual regarding transport, commissioning, operation
and maintenance of the device.
•Unauthorised changes to the device made by parties other than the manufacturer.
•Non-observance of technical data.
•Repairs carried out incorrectly.
•The use of accessories or spare parts that are not provided, approved or recommended by the
manufacturer.
•Catastrophes caused by external influences and force majeure.
•Mounting and installation with device combinations not approved or recommended by the manufacturer.
This operating manual and the enclosed safety instructions must be observed by all persons working with the
device. Furthermore, the rules and regulations that apply for accident prevention at the place of use must be
observed.
1.9 Disposal of Bende devices
Abide by the national regulations and laws governing the disposal of this device.
For more information on the disposal of Bender devices, refer to
www.bender.de > service & support.
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ISOMETER® isoHV425 with AGH422
1.10 Safety
If the device is used outside the Federal Republic of Germany, the applicable local standards and regulations
must be complied with. In Europe, the European standard EN 50110 applies.
DANGER Risk of fatal injury due to electric shock!
Touching live parts of the system carries the risk of:
•Risk of electrocution due to electric shock
•Damage to the electrical installation
•Destruction of the device
Before installing the device and before working on its connections, make sure that the installation
has been de-energised. The rules for working on electrical systems must be observed.
isoHV425_D00082_06_M_XXEN/07.2023 7

Function
2 Function
2.1 Intended use
The ISOMETER® monitors the insulation resistance RF of unearthed AC, AC/DC and DC systems (IT systems with
nominal system voltages of 3(N AC, AC/DC 0. . .1000 V or DC 0. . .1000 V.
The maximum permissible system leakage capacitance is 150 μF.
DC components existing in AC systems do not influence the operating characteristics when a minimum load
current of DC 100 mA flows. The separate supply voltage Us allows de-energised systems to be monitored as
well.
In order to meet the requirements of the applicable standards, customised parameter settings must be made
on the equipment in order to adapt it to local equipment and operating conditions. Please heed the limits of
the range of application indicated in the technical data.
Any other use or a use that goes beyond this constitutes improper use.
To ensure that the ISOM T R® functions correctly, an internal resistance of ≤ 1 kΩ must exist between L1/+
and L2/– via the source (e.g. the transformer) or the load.
If the ISOM T R® is installed inside a control cabinet, the insulation fault message must be audible and/or
visible to attract attention.
2.2 Device featu es
•Monitoring of the insulation resistance RF for unearthed AC/DC systems
•Measuring the nominal system voltage Un (True-RMS with undervoltage/overvoltage detection
•Measuring the residual voltages UL1e (between L1/+ and earth and UL2e (between L2/– and earth
•Selectable start-up delay, response delay and delay on release
•Alarm output via LEDs ('AL1', 'AL2' , display, and alarm relays ('K1', 'K2'
•Automatic device self test with connection monitoring
•Selectable N/C or N/O relay operation
•Measured value indication via multi-functional LC display
•Activatable fault memory
•Automatic adaptation to the system leakage capacitance Ce up to 150 μF
•Two separately adjustable response value ranges from 10…500 kΩ
•isoHV425-D4-4: RS-485 (galvanically isolated including the following protocols:
– BMS (Bender measuring device interface for the data exchange with other Bender devices
– Modbus RTU
– IsoData (for continuous data output
•isoHV425-D4M-4: Analogue output (galvanically separated
•Password protection against unauthorised changing of parameters
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ISOMETER® isoHV425 with AGH422
2.3 Functional desc iption
The ISOMETER® measures the insulation resistance RF and the system leakage capacitance Ce between the
system to be monitored (L1/+, L2/– and earth (PE . The RMS value of the system voltage Un between L1/+ and
L2/–, as well as the DC residual voltages UL1e (between L1/+ and earth and UL2e (between L2/– and earth are
also measured.
From a minimum value of the nominal system voltage, the ISOMETER® determines the faulty conductor L1/+
or L2/–. The fault is indicated by a '+' or '–' sign preceding the measured value. The value range of the display is
±100 %:
Display Meaning
–100 % One-sided fault on conductor L2/–
0 % Symmetrical fault
+100 % One-sided fault on conductor L1/+
The partial resistances can be calculated from the total insulation resistance RF and the faulty conductor (R %
using the following formula:
•Fault at conducto L1/+: RL1F = (200 % * RF / (100 % + R %
•Fault at conducto L2/–: RL2F = (200 % * RF / (100 % – R %
The determined fault can be assigned to an alarm relay via the menu. If the values RF or Un exceed the response
values activated in the 'AL' menu, this will be indicated by the LEDs and relays 'K1' and 'K2' according to the
alarm assignment set in the 'out' menu. In addition, the operation of the relay (n.o. / n.c. can be set and the
fault memory 'M' can be activated.
If the values RF oder Un do not exceed their release value (response value plus hysteresis for the period toff
without interruption, the alarm relays will switch back to their initial position and the alarm LEDs 'AL1'/'AL2'
stop lighting. If the fault memory is activated, the alarm relays remain in the alarm condition and the LEDs light
until the reset button 'R' is pressed or the supply voltage Us is interrupted.
The device function can be tested using the test button 'T'.
Parameters are assigned to the device via the LCD and the control buttons on the front panel; this function
can be password-protected. Parameterisation is also possible via the BMS bus, for example by using the BMS
Ethernet gateway (COM465IP or the Modbus RTU.
The isoHV425 determines the system leakage capacitance Ce through an impedance measurement whose
frequency is adjusted to the most accurate insulation measured value possible. The measurement signal is
affected if it goes through a rectifier or inverter. This can lead to phase errors that may result in an incorrect
system leakage capacitance value Ce.
2.3.1 Monito ing the insulation esistance
The insulation resistance RF is monitored by means of the parameters 'R1' (prewarning and 'R2' (alarm (see
chapter 4.4 . The value 'R1' can only be set higher than the value 'R2'. If the insulation resistance RF reaches or
falls below the activated values 'R1' or 'R2', an alarm message is triggered. If RF exceeds the values 'R1' or 'R2'
plus the hysteresis value, the alarm will be cleared.
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Function
2.3.2 Unde voltage/ove voltage monito ing
To monitor the nominal system voltage Un, the two parameters 'U ˂' and 'U ˃' can be enabled in the response-
value menu 'AL' (chapter 4.4 . The maximum undervoltage value is limited by the overvoltage value.
The RMS value of the nominal system voltage Un is monitored. If the nominal system voltage Un reaches,
falls below, or exceeds the limit values 'U ˂' and 'U ˃', an alarm will be signalled. If the maximum permissible
nominal system voltage Un set for the ISOMETER® is exceeded, an alarm message will be triggered even if the
overvoltage limit value has been deactivated. The alarm will be deleted when the limit values plus hysteresis
(chapter 4.4.1 are no longer violated.
2.3.3 Self test / e o codes
During the normal measuring function, the isoHV425 checks its correct function in the background. In
addition, the user can trigger the following tests:
•cyclically via a timer (menu item 't' / 'test' or
•via the internal test button or
•via the external test button or
•via the communication interface (COM
If a device error occurs, all LEDs flash, the display shows the message 'E.xx' according to the following error
code table and, depending on the signalling assignment, the relays switch.
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ISOMETER® isoHV425 with AGH422
E o codes
In the event of a device error, e o codes are shown in the display. Some of these are described below:
Overview of some error codes
Error code Meaning
E.01
PE connection error
The connection of E or KE to earth is interrupted.
Action: Check connection, eliminate error. The error code will be erased automatically once the
error has been eliminated.
E.02
System connection error
The internal resistance of the system is too high or the connection of L1/+ or L2/– to the system is
interrupted. The terminals L1/+ and L2/– are connected incorrectly.
Action: Check connection, eliminate error. The error code will be erased automatically once the
error has been eliminated.
E.05
Measurement error
Due to system interferences or a device error, the insulation measured value is no longer updated.
Prewarning and alarm are set for the insulation measured value at the same time.
Calibration invalid after software update
E.05 appears together with E.08 : The software is not compatible to the calibration of the device.
Action: Install the previous software version or have the device calibrated at the factory.
E.07
Permissible system leakage capacitance Ce e ceeded
The device is not suitable for the present network leakage capacitance Ce.
Action: Uninstall the device.
E.08 Calibration error
Action: Check connection, eliminate error. If the error is still present, there is a device error.
Internal device errors 'E.xx' can be caused by external disturbances or internal hardware errors. If the error
message occurs again after the device has been restarted or after a reset to the factory settings (menu item
'FAC' , the device must be repaired. After the fault has been eliminated, the alarm relays switch back either
automatically or when the reset button is pressed. The self test can take a few minutes.
Cyclic backg ound test
The cyclic background test checks the functionality of the μC. It is not visible to the user and does not influence
the measuring function. In case of malfunction, the respective device error messages 'E.09' to 'E.16' appear.
Continuous PE connection monito ing
The connection of terminal 'E' of the AGH to the PE protective conductor is monitored continuously and
in parallel with the measuring function of the device via the input 'KE' of the ISOMETER®, which is also
connected to the PE protective conductor. When the connection is interrupted, error code 'E.01' appears for PE
connection error.
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Function
Use -cont olled test functions
The user-controlled test functions interrupt the measuring function of the device. They always include a test
of the measurement technology (error code 'E.05' and additionally a test of the connection between the
terminals L1/+ and L2/– via the system to be monitored (error code 'E.02' which can be activated by the user
(menu 'SEt' / 'nEt' . If during the system connection check a negative system voltage Un > DC –100 V is applied
to the ISOMETER®, the message 'E.02' for a system connection with reversed polarity is also displayed.
If these test functions are started via a test button or the communication interface, this can be indicated not
only by the LEDs AL1 and AL2 lighting up but also by the message 'test' via the relays (menu 'out' / 'Signalling
assignment' .
2.3.4 Ala m assignment of the ala m elays K1/K2
The notifications for 'device error', 'insulation fault', 'undervoltage/overvoltage fault', 'device test' and 'device
start with alarm' can be assigned to the alarm relays via the 'out' menu.
An insulation fault is indicated by these messages:
•'+R1' and '+R2': insulation fault assigned to conductor L1/+
•'–R1' and '–R2': insulation fault assigned to conductor L2/–
If an assignment to a conductor is not possible, e.g. due to a symmetrical insulation fault, the respective '+' and
'–' messages are set together.
The message 'test' indicates a device test triggered manually via a test button or the communication interface.
The message 'S.AL' indicates a device sta t with ala m. When the parameter value is set to 'S.AL = on' and the
supply voltage Us is connected, the ISOMETER® starts with the insulation measured value RF = 0 Ω and sets all
activated alarms. The alarms will be cleared only when the measured values are up-to-date and no thresholds
are violated. In the factory setting 'S.AL = off', the ISOMETER® starts without an alarm.
Recommendation: Set parameter value 'S.AL' identical for both relays.
2.3.5 Measu ing and esponse times
Ope ating time tae
The operating time tae is the time required by the ISOMETER® to determine the measured value. For the
insulation measured value RF, the system leakage capacitance Ce, the residual voltages UL1e and UL2e as well as
for the faulty conductor 'R%' it depends on the insulation resistance RF and the system leakage capacitance Ce.
System disturbances may lead to extended measuring times. The measuring time of the nominal system
voltage Un is independent of this and significantly shorter.
Response delay ton
The response delay ton is set uniformly for all alarm messages in the 't' menu using the parameter 'ton', while
each alarm message specified in the alarm assignment has its own timer for ton. This delay can be used for
interference suppression in the case of short measuring times.
An alarm message will only be signalled when a limit value of the respective measured value is violated for the
duration of ton. Each time the limit value is violated within the time ton, the response delay 'ton' restarts.
Total esponse time tan
The total response time tan is the sum of the operating time tae and the response delay ton.
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ISOMETER® isoHV425 with AGH422
Delay on elease toff
The delay on release toff can be set uniformly for all alarm messages using the parameter 'toff', while each alarm
message specified in the alarm assignment has its own timer for toff.
An alarm message will be signalled until the limit value of the respective measured value is no longer violated
(including hysteresis for the duration of toff without interruption. Each time a limit value is no longer violated
during toff, the delay on release 'toff' restarts.
Sta t-up delay t
After connecting the supply voltage US, the alarm output is suppressed for the time set in parameter
't' (0…10 s .
2.3.6 Passwo d p otection (on, OFF)
If password protection is activated (on , settings can only be made after entering the password (0...999 . For its
activation, see chapter 4.7.
2.3.7 Exte nal test/ eset button (T/R)
Functions
•Reset = press the external button < 1.5 s
•Reset + self test = press the external button > 1.5 s
•Stop measuring function = press and hold the external button
When the measuring function is stopped, the display shows 'StP'.
The stop function can also be triggered via an interface command, and in this case it can only be reset via the
interface.
Only one ISOMETER® may be controlled via an external test/reset button.
A galvanic parallel connection of several test or reset inputs for testing multiple insulation monitoring devices
is not allowed.
2.3.8 Fault memo y
Disabled (OFF)
The LEDs and relays signal the fault as long as it is detected.
Enabled (ON)
The LEDs and relays signal the fault until a reset is performed or the supply voltage Us is disconnected.
2.3.9 Histo y memo y HiS
The history memory saves exclusively the measured values for the first fault. The history memory must first be
cleared before new measured values can be saved.
The values checked in the table in section 'Displaying measured values' can be saved.
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Function
2.3.10 Digital inte faces (isoHV425-D4-4)
The ISOMETER® uses the serial hardware interface RS-485 with the following protocols:
•BMS
The BMS protocol is an essential component of the Bender measuring device interface (BMS bus protocol .
Data transmission generally makes use of ASCII characters.
•Modbus RTU
Modbus RTU is an application layer messaging protocol, and it provides master/slave communication
between devices that are connected via bus systems and networks. Modbus RTU messages have a 16-bit
CRC (cyclic redundant checksum , which guarantees reliability.
•IsoData
The ISOMETER® sends an ASCII data string with a cycle of approximately 1 second. Communication with
the ISOMETER® in this mode is not possible, and no additional sender may be connected via the RS-485 bus
cable. The ASCII data string for the ISOMETER® is described in chapter 5.4.
The IsoData protocol can be terminated by sending the command 'Adr3' during a transmission pause of
the ISOM T R®.
The parameter address, baud rate and parity for the interface protocols are configured in the 'out' menu.
With 'Adr = 0', the menu entries baud rate and parity are not shown in the menu and the IsoData protocol
is activated.
With a valid bus address (i.e. not equal to 0), the menu item 'baud rate' is displayed in the menu. The
parameter value '---' for the baud rate indicates the activated BMS protocol. In this case, the baud rate
for the BMS protocol is set to 9600 baud. If the baud rate is set unequal to '---', the Modbus protocol with
configurable baud rate is activated.
2.3.11 Analogue inte face (isoHV425-D4M-4)
The following functions can be selected at the potential-free analogue signal output:
•Voltage output DC 0…10 V
•Current output DC 4…20 mA
•Current output DC 0…20 mA
•Current output DC 0…400 μA
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ISOMETER® isoHV425 with AGH422
3 Installation, connection and commissioning
3.1 Dimensions
36
93
74.5
90 45 70.5
47.5
31.1
Figure: Dimension diagram (in mm
3.2 Installation
Application in rail vehicles/DIN EN 55 5-2:2016
If the distance to neighbouring components that do not comply with the requirement of DIN N 45545-2
table 2 is <20 mm horizontally or <200 mm vertically, these components shall be considered grouped. See
DIN N 45545-2 Section 4.3 grouping rules.
Figure: DIN rail mounting (left or screw mounting (right
isoHV425_D00082_06_M_XXEN/07.2023 15

Installation, connection and commissioning
3.3 Connection
CAUTION Danger from touching hot surfaces!
If the AGH is operated at mains voltages > 800 V, the temperature of the enclosure may exceed 60 °C.
•Do not touch the surfaces of the device after connecting it to the mains voltage.
For details about the required conductor cross sections, refer to chapter 'Technical data'.
Wi ing diag am legend:
Terminal Connections
A1, A2 Connection to the supply voltage Us via fuse:
If supplied from an IT system, both lines have to be protected by a fuse.*
E, E, KE Connect each terminal separately to PE:
Use the same wire cross section as for A1 , A2 .
L1/+, L2/– Connection to IT system to be monitored
Up, AK1, GND, AK2 Connect the terminals of the AGH to the corresponding terminals of the ISOMETER®.
T/R Connection for external combined test and reset button
11, 14 Connection to alarm relay K1
11, 24 Connection to alarm relay K2
A, B RS-485 communication interface with selectable terminating resistance
M–, M+ Analogue output
* For UL applications:
Only use 60/75 °C copper lines!
UL and CSA applications require the supply voltage Us to be protected via 5 A fuses.
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ISOMETER® isoHV425 with AGH422
Wi ing diag am fo isoHV425(W)-D4-4
Figure: Wiring diagram with RS-485 interface
isoHV425_D00082_06_M_XXEN/07.2023 17

Installation, connection and commissioning
Anschlusszeichnung fo isoHV425(W)-D4M-4
Figure: Wiring diagram with analogue interface
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ISOMETER® isoHV425 with AGH422
3.4 Commissioning
1. Check that the ISOMETER® is p ope ly connected to the system to be monito ed.
2. Connect supply voltage Us to the ISOMETER®.
The device carries out a calibration, a self test and adjusts itself to the IT system to be monitored. With
high system leakage capacitances this process may take up to 4 min. The standard display then appears
showing the present insulation resistance, e.g.:
The pulse symbol signals an error-free update of the resistance and capacitance measured values. If
the measured value cannot be updated due to disturbances, the pulse symbol will be blanked.
3. Sta t a manual self test by pressing the test button 'T' > 1.5 s. While holding the test button all available
display elements are shown. After releasing the button, the test starts and ‘tES’ flashes for the duration of
the test. Detected malfunctions are displayed as error codes (see chapter 2.3.3.1 .
The alarm relays are not checked during the test (factory setting). The setting can be changed in the
'out' menu so that the relays switch to the alarm state during the manual self test.
4. Check if the settings a e suitable fo the system being monito ed.
The list of factory settings is shown in the tables from chapter 4.4.
For networks with a leakage capacitance > 5 μF, the response value Ran1 should be set to a maximum
of 200 kΩ due to the increased measurement tolerance.
5. Check the functionality by a eal insulation fault.
Use a suitable resistor to check the ISOMETER® against earth in the system being monitored.
isoHV425_D00082_06_M_XXEN/07.2023 19

Operation
4 Ope ation
4.1 Ope ating and display elements
Device front Operating elements Function
ON Device is running
AL1 Prewarning
Overvoltage
AL2 Alarm
Undervoltage
Up and down buttons
– For navigating up or down in the
menu settings.
– For increasing or decreasing values.
TTest button (press >1.5s)
RReset button (press >1.5s)
Enter button
– Select menu item.
– Save value.
MENU MENU button (press >1.5s)
– Starts menu mode.
– Exits menu item without saving
changes.
LED on
LED flashes
The 'prewarning' and 'alarm' messages can be assigned to the relays, see chapter 4.5.2.
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