Bender ISOMETER isoRW425 User manual

Manual EN
ISOMETER® isoRW425
Insulation monitoring device
for unearthed AC-, AC/DC and DC systems
in railway applications up to 3(N AC, AC/DC 440 V
Software version: D0418 V2.xx
isoRW425_D00052_06_M_XXEN/09.2023

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ISOMETER® isoRW425
Table of contents
1General information...........................................................................................5
1.1 How to use the 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...................................................................................................................6
1.6 Delivery conditions......................................................................................................................................... 6
1.7 Inspection, transport and storage.............................................................................................................6
1.8 Warranty and liability.....................................................................................................................................6
1.9 Disposal of Bender devices..........................................................................................................................7
1.10 Safety.................................................................................................................................................................... 7
2F nction...............................................................................................................8
2.1 Intended use......................................................................................................................................................8
2.2 Device features................................................................................................................................................. 8
2.3 Functional description...................................................................................................................................9
2.3.1 Monitoring the insulation resistance (R mode ....................................................................................9
2.3.2 Monitoring of the insulation impedance (Z mode ......................................................................... 10
2.3.3 Undervoltage/overvoltage monitoring................................................................................................ 10
2.3.4 Self test/error codes.....................................................................................................................................10
2.3.5 Malfunction......................................................................................................................................................12
2.3.6 Alarm assignment of the alarm relays K1/K2..................................................................................... 12
2.3.7 Measuring and response times................................................................................................................12
2.3.8 Password protection (on, OFF ................................................................................................................ 13
2.3.9 External test/reset button (T/R ............................................................................................................... 13
2.3.10 Fault memory..................................................................................................................................................14
2.3.11 History memory HiS..................................................................................................................................... 14
2.3.12 Digital interface..............................................................................................................................................14
3Installation, connection and commissioning.................................................15
3.1 Dimensions...................................................................................................................................................... 15
3.2 Installation........................................................................................................................................................15
3.3 Connection.......................................................................................................................................................16
3.4 Commissioning...............................................................................................................................................17
4Operation.......................................................................................................... 18
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Table of contents
4.1 Operating and display elements.............................................................................................................18
4.2 Menu overview...............................................................................................................................................20
4.3 Displaying measured values..................................................................................................................... 21
4.4 Setting the response values (AL ............................................................................................................ 22
4.4.1 Setting the response values for monitoring the insulation resistance (R mode or the
insulation impedance (Z mode ...............................................................................................................22
4.4.2 Setting the response values for undervoltage and overvoltage.................................................22
4.4.3 Response values overview.........................................................................................................................22
4.5 Configuring fault memory, alarm relays, and interfaces (out ......................................................23
4.5.1 Configuring the relays.................................................................................................................................23
4.5.2 Assigning the alarm messages to the relays...................................................................................... 23
4.5.3 Activating or deactivating fault memory.............................................................................................24
4.5.4 Configuring interface...................................................................................................................................24
4.6 Setting delay times and self test cycles (t .......................................................................................... 25
4.7 Setting device control parameters (SEt ...............................................................................................25
4.8 Reset to factory settings.............................................................................................................................26
4.9 Showing and deleting the history memory........................................................................................26
4.10 Querying software version (InF .............................................................................................................. 26
5Data access via RS-485 interface.....................................................................27
5.1 Data access using the BMS protocol..................................................................................................... 27
5.2 Data access using the Modbus RTU protocol.................................................................................... 27
5.2.1 Reading out the Modbus register from the ISOMETER®.................................................................27
5.2.2 Writing the Modbus register (parameter setting .............................................................................28
5.2.3 Exception code...............................................................................................................................................29
5.3 Modbus register assignment.................................................................................................................... 30
5.3.1 Modbus measured value registers......................................................................................................... 30
5.3.2 Modbus parameter register...................................................................................................................... 33
5.4 IsoData data string....................................................................................................................................... 37
6Technical data...................................................................................................39
6.1 Technical data isoRW425........................................................................................................................... 39
6.2 Connection.......................................................................................................................................................43
6.3 Standards and certifications..................................................................................................................... 44
6.4 Ordering data..................................................................................................................................................44
6.5 Change log.......................................................................................................................................................45
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ISOMETER® isoRW425
1 General information
1.1 How to se the man al
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 important instr ctions and information
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.
ADVICE
Indicates important facts that do not result in immediate injuries. They can lead to malfunctions if the
device is handled incorrectly.
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 Service and S pport
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.
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General information
1.5 Training co rses and seminars
Regular face-to-face or online seminars for customers and other interested parties:
www.bender.de > know-how > seminars.
1.6 Delivery 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, transport and storage
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 Warranty 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.
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ISOMETER® isoRW425
1.9 Disposal of Bender 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.
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.
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Function
2 F nction
2.1 Intended se
The ISOMETER® monitors the insulation resistance RF (R mode or the insulation impedance (Z mode
of unearthed AC/DC main circuits (IT systems with nominal system voltages of 3(N AC, AC, AC/DC or
DC 0…440 V .
DC components existing in 3(N AC, AC/DC systems do not influence the operating characteristics when a
minimum load current of DC 10 mA flows. The separate supply voltage Us allows de-energised systems to be
monitored as well.
The maximum permissible system leakage capacitance is 300 μF in R mode and 1 μF in Z mode.
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. PSU) 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 feat res
•Monitoring of the insulation resistance RF (R mode or of the insulation impedance ZF (Z mode for
unearthed 3(N AC, AC and DC systems with galvanically connected rectifiers or frequency converters
•Insulation impedance ZF (Z mode for 50 Hz or 60 Hz
•Measuring the system voltage Un (True-RMS with undervoltage/overvoltage detection
•Measuring the DC 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 300 μF in R mode and 1 μF in Z mode
•Two separately adjustable response value ranges from 1…990 kΩ (prewarning, alarm
•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
•Password protection against unauthorised changing of parameters
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ISOMETER® isoRW425
2.3 F nctional description
The ISOMETER® measures the insulation resistance RF and the system leakage capacitance Ce between the
system to be monitored (L1/+, L2/– and earth (PE . Z mode (selectable in the “SEt” menu calculates the
insulation impedance ZF from RF and Ce with a system frequency parameter fn = 50 Hz or fn = 60 Hz. The RMS
value of the system voltage Un between L1/+ and L2/– as well as the residual voltages UL1e (between L1/+ and
earth and UL2e (between L2/– and earth are also measured.
From a minimum system voltage, the ISOMETER® determines the faulty conductor “R %”, which shows the
distribution of the insulation resistance between conductors L1/+ and L2/–. The distribution is indicated by
a positive or negative sign preceding the insulation resistance measurement. The value range of the faulty
conductor is ±100 %:
Indication Meaning
–100 % one-sided fault at conductor L2/–
0 % symmetrical fault
+100 % one-sided fault at conductor L1/+
The partial resistances can be calculated from the total insulation resistance RF and the faulty conductor “R %”
using the following formula:
•Fa lt at cond ctor L1/+: RL1F = (200 % × RF / (100 % + R %
•Fa lt at cond ctor L2/–: RL2F = (200 % × RF / (100 % – R %
Also from a minimum system voltage, the ISOMETER® determines the insulation resistance RUGF from the
residual voltages UL1e and UL2e. It is an approximate value for one-sided insulation faults and can be used as a
trend indicator in cases where the ISOMETER® has to adapt to an RF and Ce relation that varies considerably.
The detected fault is assignable to an alarm relay via the menu. If the values RF, ZF or Un violate the response
values activated in the “AL” menu, this will be indicated by the LEDs and relays “K1” and “K2” according to the
signalling assignment set in the “out” menu. In addition, the menu offers the setting of the relay operation and
the activation of the fault memory “M”.
If the values RF, ZF or Un do not violate 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 stop lighting.
If the fault memory is activated, the alarm relays remain in alarm position and the LEDs are lit until the reset key
“R” is pressed or the supply voltage Us is interrupted.
The device function can be checked with 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.
2.3.1 Monitoring the ins lation resistance (R mode)
The insulation resistance RF is monitored by means of the parameters “R1” (prewarning and “R2” (alarm (see
chapter 4.4.3 . 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
ach time the mode is switched from R mode to Z mode, parameters “R1” and “R2”, and hence the
monitoring of the insulation resistance RF will be deactivated.
In Z mode the insulation impedance ZF is the main measured value and the measured insulation
resistance RF may have increased tolerances depending on the system condition. If required, the
parameters “R1” and “R2” can also be activated in Z mode.
2.3.2 Monitoring of the ins lation impedance (Z mode)
In Z mode the parameters “Z1” and “Z2” for monitoring the insulation impedance ZF are available in the “AL”
menu. The value “Z1” must be set higher than value “Z2”. The insulation impedance ZF for the selected system
frequency fn (50 Hz or 60 Hz in the “SEt” menu can be calculated from the measured values RF and Ce using the
formula below:
The lower resistance component of RF or Xce determines the amount of ZF. The higher resistance component of
RF or Xce may have an increased tolerance due to the measuring signal resolution.
If the insulation impedance ZF reaches or falls below the activated values “Z1” or “Z2”, an alarm message will
be signalled. If ZF exceeds the values “Z1” or “Z2” plus the hysteresis value (see table in chapter 4.4.3 , the alarm
will be cleared.
2.3.3 Undervoltage/overvoltage monitoring
To monitor the 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 system voltage Un is monitored. If the system voltage Un reaches, falls below, or exceeds
the limit values “U˂” and “U˃”, an alarm will be signalled. If the maximum permissible 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.
2.3.4 Self test/error codes
The self test checks the function of the ISOMETER®, and monitors the connection to earth as well as the
connection to the system to be monitored. The alarm relays do not switch during an automatically started self
test. For a self test started manually, the switching of the alarm relays can be set using the parameter “test” in
the alarm assignment (menu “out”, chapter 4.5.2 . During the test, the display indicates “tES”.
When malfunctions are detected or connections are missing, the LEDs “ON”/“AL1”/“AL2” flash. The display
shows the respective error codes (“E.xx” , and in the factory setting relay “K2” switches. The relays can be
assigned to a device error with the parameter “Err” in the “out” menu in the alarm assignment.
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ISOMETER® isoRW425
2.3.4.1 Error codes
In the event of a device error the display shows the respective error code.
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 automaticall once the
error has been eliminated.
E.02
System connection error
The internal resistance of the s stem is too high or the connection of “L1/+” or “L2/–” to the s stem
is interrupted. The terminals “L1/+” and “L2/–” are connected incorrectl .
Action: Check connection, eliminate error. The error code will be erased automaticall once the
error has been eliminated.
E.05
Measurement error
Due to s stem 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 factor .
E.07
Permissible system leakage capacitance Ce exceeded
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.
2.3.4.2 A tomatic self test
In the factory setting a self test is carried out when the supply voltage Us is connected and after that every 24 h.
This cycle can be adjusted: off, 1 h, 24 h (see chapter 4.6 .
The self test can be disabled for the device start so that the device can enter the measurement mode more
quickly. To this end, set the parameter “S.Ct = off” in the menu “SEt”.
2.3.4.3 Man al self test
The manual self test is started by pressing the external test/reset button or the test button “T” on the device for
˃ 1.5 s. Holding the test button “T” also shows all display elements.
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Function
2.3.4.4 Connection monitoring
Connection monitoring, activated by the self test, checks the connections of terminals “E” and “KE” to the
protective earth conductor (PE . When an error is detected, the message device error (“Err” is signalled and the
error code “E.01” appears on the display.
The system connection monitoring checks the connection of terminals “L1/+” and “L2/–” to the system to be
monitored. When an interruption or a high-resistance connection between L1/+ and L2/– is detected via the
internal resistance of the system, the device error (“Err” is signalled and the error code “E.02” appears on the
display. Since a test of the system connection may take considerable time or even provide incorrect resultsdue
due to system disturbances, the connection monitoring can be switched off using the parameter “nEt” in the
“SEt” menu.
2.3.5 Malf nction
The device checks some of its functions continuously during operation. If a fault is detected, the device
error (“Err” will be signalled, “E.xx” appears on the display as an identifier for error type xx, and the LEDs
“ON”/“AL1”/“AL2” will flash.
Please contact Bender Service, if the error occurs again after the device has been restarted or the factory
settings have been restored.
2.3.6 Alarm assignment of the alarm relays 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 ins lation fa lt 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 inter-
face.
The message “S.AL” indicates a device start with alarm. 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
ZF = 0 Ω in Z mode 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.
2.3.7 Meas ring and response times
Operating 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.
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ISOMETER® isoRW425
Example: A maximum permissible system leakage capacitance of Ce = 300 μF and an insulation fault of
RF = 2.5 kΩ (Ran = 5 kΩ in a DC 400 V system result in an operating time of tae < 40 s.
System disturbances may lead to extended measuring times. The measuring time of the 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 response time tan
The total response time tan is the sum of the operating time tae and the response delay ton.
Delay on release 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.
Start- p delay t
After connecting the supply voltage US, the alarm output is suppressed for the time set in parameter
“t” (0…10 s .
2.3.8 Password protection (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.
2.3.9 External test/reset b tton (T/R)
F nctions
•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”.
Stop mode 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.
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Function
2.3.10 Fa lt memory
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.
2.3.11 History memory 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”, page 21 can be saved.
2.3.12 Digital interface
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.
•Modb s 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.
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ISOMETER® isoRW425
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
isoRW425_D00052_06_M_XXEN/09.2023 15

Installation, connection and commissioning
3.3 Connection
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.
For details about the conductor cross sections required for wiring, refer to chapter "6 Technical data".
Wiring diagram
US
KE
A1
A2
14
24 11
K1
K2
Test / Reset
COM465IP
RS-485
E
6 A
6 A
L1/+
L2/-
PE
L3
A
B
R
L2/-
L1/+
T/R
ON
AL1
AL2 k
T R MENU
Ron
off
14
24 11
A
T/R
B
L1/+
L2/-
E KE
A2A1
Figure: Wiring diagram
erminal Connections
A1, A2 Connection to the suppl voltage Us via
fuse (line protection):
If supplied from an IT s stem, protect both
lines b a fuse.*
E, KE Connect each terminal separatel to PE:
Use same wire cross section as for “A1”,
“A2”.
L1/+,
L2/–
Connection to the s stem to be monitored
/R Connection for the external combined test
and reset button
11, 14 Connection to alarm rela “K1”
11, 24 Connection to alarm rela “K2”
A, B RS-485 communication interface with
connectable terminating resistor
Example: Connection of a BMS Ethernet
gatewa COM465IP
* For UL applications:
Use 60/75 °C copper lines only!
For UL and CSA applications, connect the supply voltage Us via 5 A fuses.
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ISOMETER® isoRW425
3.4 Commissioning
1. Check that the ISOMETER® is properly connected to the system to be monitored.
2. Connect s pply 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. Start a man al 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 2.3.4.1 .
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 are s itable for the system being monitored.
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 f nctionality by a real ins lation fa lt.
Use a suitable resistor to check the ISOMETER® against earth in the system being monitored.
isoRW425_D00052_06_M_XXEN/09.2023 17

Operation
4 Operation
4.1 Operating 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.
Test 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
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ISOMETER® isoRW425
Display Display elements Function
US stem voltage Un
IAmperage In
RInsulation resistance RF
ZImpedance ZF
CS stem leakage capacitance Ce
L1 L2 Monitored conductors
Voltage t pe DC
Pulse s mbol: error-free measured
value update
Voltage t pe AC
°C
μ n F Hz
k M Ω %
m V A s
Measured values and units
Password protection is activated
In the menu mode, the operating
mode of the respective alarm rela is
displa ed.
Adr Communication interface with
measured value: isoData operation
MFault memor is activated
on / off Condition s mbols
test Self test is active
>
+
<
Identification for response values and
response value violation
The display parameters that can be configured flash.
The readability below –25 °C is limited.
Depending on the ISOM T R®'s scope of functions, not all display elements are used.
isoRW425_D00052_06_M_XXEN/09.2023 19

Operation
4.2 Men overview
Meas rement display Men selection Parameter selection
Menu item Parameter
AL Quer ing and setting response values
out Configuring fault memor , alarm rela s and interface
tSetting dela times and self test c cles
SEt Setting device control parameters
InF Quer ing software version
HiS Quer ing and clearing the histor memor
ESC Going to the next-higher menu level
20 isoRW425_D00052_06_M_XXEN/09.2023