Bender ISOMETER isoCHA425HV User manual

Manual EN
ISOMETER® isoCHA425HV
Insulation monitoring device with coupling device AGH420-1/AGH421-1
For unearthed D systems 0 V to 1000 V
Suitable for D charging stations according to S or HAdeMO
Software version: D0624 V4.xx
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ISOMETER® iso HA425HV
Table of contents
1General infor ation...........................................................................................6
1.1 How to use the manual.................................................................................................................................6
1.2 Indication of important instructions and information.......................................................................6
1.3 Signs and symbols...........................................................................................................................................6
1.4 Service and Support....................................................................................................................................... 6
1.5 Training courses and seminars...................................................................................................................7
1.6 Delivery conditions......................................................................................................................................... 7
1.7 Inspection, transport and storage.............................................................................................................7
1.8 Warranty and liability.....................................................................................................................................7
1.9 Disposal of Bender devices..........................................................................................................................8
1.10 Safety.................................................................................................................................................................... 8
2Function...............................................................................................................9
2.1 Intended use......................................................................................................................................................9
2.2 Device features................................................................................................................................................. 9
2.3 Functional description.................................................................................................................................10
2.3.1 RF and Ce in “ Hd” and “ HA” mode ( HAdeMO)............................................................................11
2.3.2 RF and Ce in “dc” mode ( S)...................................................................................................................11
2.3.3 Fault location R%.......................................................................................................................................... 11
2.3.4 System leakage capacitance Ce............................................................................................................... 11
2.3.5 System voltages Un, UL1e and UL2e.......................................................................................................... 11
2.3.6 Functional tests of contactors in the charging station and the vehicle....................................12
2.3.7 Monitoring the insulation resistance.....................................................................................................12
2.3.8 Undervoltage/overvoltage monitoring................................................................................................ 12
2.3.9 Stop mode....................................................................................................................................................... 12
2.3.10 Self test functions (device errors)........................................................................................................... 12
2.3.11 Error codes.......................................................................................................................................................14
2.3.12 Alarm assignment of the alarm relays K1/K2..................................................................................... 14
2.3.13 Fault memory..................................................................................................................................................15
2.3.14 Digital interface..............................................................................................................................................15
2.3.15 Measuring and response times................................................................................................................16
2.3.16 Password protection (on, OFF)................................................................................................................ 16
2.3.17 External test/reset button (T/R)............................................................................................................... 16
2.3.18 History memory HiS..................................................................................................................................... 17
3Installation, connection and co issioning.................................................18
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Table of contents
3.1 Dimensions...................................................................................................................................................... 18
3.2 Installation........................................................................................................................................................18
3.3 onnection.......................................................................................................................................................18
3.4 ommissioning...............................................................................................................................................21
4Operation.......................................................................................................... 22
4.1 Operating and display elements.............................................................................................................22
4.2 Menu overview...............................................................................................................................................24
4.3 Displaying measured values..................................................................................................................... 25
4.4 Setting the response values (AL)............................................................................................................ 26
4.4.1 Response values overview.........................................................................................................................26
4.4.2 Setting the response values for monitoring the insulation resistance......................................26
4.4.3 Setting the response values for undervoltage and overvoltage.................................................26
4.5 onfiguring fault memory, alarm relays, and interfaces (out)......................................................26
4.5.1 onfiguring the relays.................................................................................................................................27
4.5.2 Assigning the alarm messages to the relays...................................................................................... 27
4.5.3 Activating or deactivating fault memory.............................................................................................28
4.5.4 onfiguring interface...................................................................................................................................28
4.6 Setting delay times and self test cycles (t).......................................................................................... 28
4.7 Setting device control parameters (SEt)...............................................................................................29
4.8 Reset to factory settings.............................................................................................................................29
4.9 Showing and deleting the history memory........................................................................................29
4.10 Querying software version (InF).............................................................................................................. 30
5Data access via RS-485 interface.....................................................................31
5.1 Data access using the BMS protocol..................................................................................................... 31
5.2 Data access using the Modbus RTU protocol.................................................................................... 31
5.2.1 Reading out the Modbus register from the ISOMETER®.................................................................31
5.2.2 Writing the Modbus register (parameter setting).............................................................................32
5.2.3 Exception code...............................................................................................................................................33
5.3 Modbus register assignment.................................................................................................................... 34
5.3.1 Modbus measured value registers......................................................................................................... 34
5.3.2 Modbus parameter register...................................................................................................................... 37
5.4 IsoData data string....................................................................................................................................... 41
6Technical data...................................................................................................42
6.1 Technical data iso HA425HV................................................................................................................... 42
6.2 Technical data AGH420-1 and AGH421-1............................................................................................47
6.3 onnection (for ISOMETER® and AGH) (for ISOMETER® and ZE420)...........................................48
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ISOMETER® iso HA425HV
6.4 Standards and certifications..................................................................................................................... 49
6.5 Ordering data..................................................................................................................................................50
6.6 Document revision history........................................................................................................................ 50
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General information
1 General infor ation
1.1 How to use the anual
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 i portant instructions and infor ation
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 sy bols
Disposal Protect from moisture Protect from dust
Temperature range Recycling RoHS directives
1.4 Service and Support
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 & o. KG.
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ISOMETER® iso HA425HV
1.5 Training courses and se inars
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 & o. 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
heck 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.
•atastrophes 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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General information
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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ISOMETER® iso HA425HV
2 Function
2.1 Intended use
The ISOMETER® iso HA425HV in combination with the AGH420-1/AGH421-1 coupling device monitors the
insulation resistance RF for D fast charging stations according to the HAdeMO standard or according to the
ombined harging System ( S) for nominal system voltage ranges between D 0 V and 1000 V.
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 ISO ETER® 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 ISO ETER® is installed inside a control cabinet, the insulation fault message must be audible and/or
visible to attract attention.
2.2 Device features
•Monitoring of the insulation resistance RF of D charging stations in accordance with the HAdeMO
standard or ombined harging System ( S)
•HAdeMO (Mode Hd and HA):
– Maximum system leakage capacitance 1.6 μF per conductor
– Detection of insulation faults in the system voltage range from 50 V to 1000 V
– Response time for one-pole insulation faults RFU:
•RFU ≤ 100 kΩ: max. 1 s
•100 kΩ < RFU ≤ 2 MΩ: max. 10 s
– Response time for two-pole insulation faults RFS (Mode Hd only):
•RFS ≤ 160 kΩ: max. 10 s
•RFS > 160 kΩ (200 kΩ): no detection (deactivation)
•S (Mode dc):
– Detection of insulation faults up to 2 MΩ
– Maximum system leakage capacitance Ce: 20 μF
– Response time tan at Ce ≤ 5 μF or RF ≤ 100 kΩ: max. 10 s
•Measuring the system leakage capacitance Ce
•Measuring the system voltage Un (True-RMS) with undervoltage/overvoltage detection
•Measuring the D residual voltages UL1e (L1/+ to PE) and UL2e (L2/– to PE)
•Selectable start-up delay, response delay and delay on release
•Two separately adjustable response value ranges from 5…600 kΩ (prewarning, alarm)
•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 L display
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Function
•Activatable fault memory
•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
•Stop mode for disabling the measuring pulse generator and in combination with AGH421-1 disconnection
from the monitored system.
2.3 Functional description
The ISOMETER® is designed for use in D charging stations according to HAdeMo standard or ombined
harging System ( S) and can be set to the respective mode in the “SEt” menu via the Mode parameter.
It measures:
•the total insulation resistance RFS
•the one-sided insulation resistance RFU
•the system leakage capacitance Ce
•the system voltage Un (True RMS) between L1/+ and L2/–
•the D system voltages (residual voltages) UL1e and UL2e between L1/+ as well as L2/– and earth
Depending on the selected mode, RFS and RFU are combined to the value RF. For RF a prewarning and an alarm
limit value can be set in the “AL” menu. The prewarning limit value can only be set higher than the alarm limit
value. If the measured value reaches or falls below the limit values, an alarm is signalled. For the measured
value Un an overvoltage and undervoltage limit value can be enabled and adjusted, the violation of which
triggers an alarm. The limit value alarms are deleted when the respective measured value no longer violates
the limit value including the corresponding hysteresis.
All alarms generated by the ISOMETER® are signalled via the LEDs “AL1” and “AL2”. In the “out” menu, the
alarms can be assigned to the alarm relays (“K1”, “K2”). In addition, the operation of the alarm relays (n.o./n.c.)
can be configured and the fault memory “M” can be activated or deactivated. If the fault memory is activated,
the alarm relays remain in alarm condition until the reset button “R” is pressed or the supply voltage Us is
interrupted.
In the “t” menu, the start-up delay at device start, the response delay and the delay on message release as well
as the repetition time of the automatic device self test can be set.
For the RS-485 interface, the protocols BMS, Modbus RTU or isoData are selected in the “out” menu. The
measured values can be read and the parameters of the ISOMETER® can be set via the BMS protocols, e.g. using
the BMS Ethernet gateway ( OM465IP) and Modbus RTU. If the isoData protocol is selected, the ISOMETER®
only sends the measured values, once per second.
The device function can be tested using the test button “T”.
The device parameters are set via the L display and via the control buttons on the front panel. This function
can be password-protected.
The ISOMETER® can be set to stop mode to deactivate the measuring pulse generator. Using the AGH421-1,
stop mode also disconnects the ISOMETER® from the monitored system.
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ISOMETER® iso HA425HV
2.3.1 RF and Ce in “CHd” and “CHA” ode (CHAdeMO)
The insulation fault RF and the system leakage capacitance Ce are only determined for D system voltages
≥ 50 V. The maximum permissible system leakage capacitance Ce is 1.6 μF per conductor. In mode “ Hd”
the value RF is determined by the smaller of the values RFU and RFS. RFU is the one-pole total insulation fault
determined from the voltages UL1e and UL2e up to a maximum of 2 MΩ.
RFS is the two-pole insulation fault. It is only determined up to a maximum of 160 kΩ. As soon as RFS falls below
160 kΩ, it is thereafter evaluated up to max. 200 kΩ.
The response time of the one-pole insulation fault RFU is 1 s for limit values up to 100 kΩ and Un ≥ 100 V. For
values outside these ranges, the response time of RF is max. 10 s.
In “ HA” mode, only the one-pole insulation fault RFU is evaluated and not the two-pole isolation fault RFS.
2.3.2 RF and Ce in “dc” ode (CCS)
The insulation fault RF up to 2 MΩ and the system leakage capacitance Ce are determined independently of
the system voltage. The maximum permissible system leakage capacitance is 20 μF. The response time for RF is
10 s.
2.3.3 Fault location R%
From Un > D 20 V the fault location R% is calculated for insulation faults RF up to 500 kΩ (“ Hd” mode 150 kΩ).
Value Meaning
–100 % one-pole insulation fault at L2/–
0 % symmetrical insulation fault
+100 % one-pole insulation fault at L1/+
For values of 30 % and more, the alarm assignment of the relays distinguishes between insulation faults at
L1/+ and L2/–.
From the values R% and RF the partial resistances RF+ and RF– can be calculated using the following formulas:
•Fault at conductor D +: RF+ = (200 % × RF) / (100 % + R%)
•Fault at conductor D –: RF– = (200 % × RF) / (100 % – R%)
2.3.4 Syste leakage capacitance Ce
The system leakage capacitance Ce is determined for insulation faults RF > 10 kΩ up to a value of 35 μF. Above
30 μF, the message Device error “E.07” is displayed.
For applications according to UL 2231-1/-2, the system leakage capacitance Ce is limited to 10 μF.
2.3.5 Syste voltages Un, UL1e and UL2e
The system voltage Un between terminals L1/+ and L2/– is measured as RMS value (True-RMS). Limit values
for overvoltage and undervoltage are available in the “A” menu; see “Setting the response values (AL)”,
page 26. Above 1200 V, the message “Overvoltage” is displayed regardless of the set overvoltage limit
value.
The D system voltages UL1e and UL2e are respectively measured between terminals L1/+ as well as L2/– and
earth. No limit value is assigned to them.
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Function
2.3.6 Functional tests of contactors in the charging station and the vehicle
If the ISOMETER® is disconnected on one pole from the monitored voltage source during a functional test of
the charging station or vehicle contactors, a false alarm may occur depending on the location of an existing
insulation fault. For insulation faults above 600 kΩ the false alarm can be prevented by a resistor of 200 kΩ
connected directly between the terminals L1/+ and L2/–.
2.3.7 Monitoring the insulation resistance
The insulation resistance RF is monitored by means of the parameters “R1” (prewarning) and “R2” (alarm) (see
chapter 4.4.1). 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.
2.3.8 Undervoltage/overvoltage onitoring
To monitor the system voltage Un, the two parameters “U˂” and “U˃” can be enabled in the response-value
menu “AL” (see 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 (see chapter 4.4.2) are no longer
violated.
2.3.9 Stop ode
If the measuring pulse interferes with other measuring functions, the ISOMETER® can be set to stop mode,
either via the Modbus protocol or by holding the external test/reset button (“T/R”).
In stop mode, the measuring pulse generator stops clocking and the measuring function is deactivated. The
message “StP” appears on the display. The communication interface returns the identifiers “warning” and
“external test”.
For applications where the ISOMETER® is temporarily not needed and if it is coupled with the AGH421-1, the
isometer can be disconnected from the monitored system by activating stop mode via the Modbus protocol.
There is no disconnection if stop mode is activated via the external test/reset button.
2.3.10 Self test functions (device errors)
During the normal measuring function the cyclic test of the µ as well as the continuous PE connection
monitoring run in the background.
User-controlled test functions interrupt the measuring function of the device. They are triggered as follows:
•cyclically via a timer (menu item “t” / “test”) or
•via the internal or external test button or
•via the communication interface ( OM)
In case of a device error, all LEDs flash, the display shows the message “E.xx” according to the table in the
section “Error codes”, page 14 and, depending on the message assignment, the relays switch.
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ISOMETER® iso HA425HV
2.3.10.1 Cyclic background test
The cyclic background test checks the functionality of the μ . 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.
2.3.10.2 Continuous PE connection onitoring
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.
2.3.10.3 User-controlled 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 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”).
Syste connection test
The system connection test configurable in the menu “SEt”/“nEt” checks the connection between the terminals
L1/+ and L2/– via the monitored system. For the ISOMETER® to function correctly, the monitored system must
have a low internal resistance Ri < 1 kΩ.
The “on” setting is used in systems with Un < D 100 V. When “on U” is set, the system voltage must be
Un > D 100 V during the test.
If an error is detected, the message Device error system connection “E.02” appears. If the System voltage Un
is below D –30 V during the mains connection test, the message Device error polarity reversal “E.03” also
appears.
Internal and external test button
Pressing the external test/reset button or the test button “T” on the device (> 1.5 s) starts the user-controlled
test functions. Holding the test button “T” on the device also shows all available display elements.
Ti er for test functions
At menu item “t”/“test” the user-controlled test can be activated in a cycle of one or 24 hours. The timer
restarts after each completed test, regardless of whether it was triggered by the timer or manually.
Device test at device start
At menu item “SEt”/“S. t” the execution of the user-controlled test functions can be activated for the time of
the device start.
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Function
2.3.11 Error codes
In the event of a device error the display shows the respective error code.
Overview of so e 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.03
Reversed polarity connection error
Terminals “L1/+” and “L2/–” are connected to the DC s stem to be monitored with reversed polarit .
Detection from Un ˂ DC –30 V
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 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
“FA ”), 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.
2.3.12 Alar assign ent of the alar 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 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.
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ISOMETER® iso HA425HV
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 alar . 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
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.
2.3.13 Fault e ory
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.
2.3.14 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 AS II 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
R (cyclic redundant checksum), which guarantees reliability.
•IsoData
The ISOMETER® sends an AS II data string with a cycle of approximately 1 second. ommunication with
the ISOMETER® in this mode is not possible, and no additional sender may be connected via the RS-485 bus
cable. The AS II 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 ISO ETER®.
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 B S protocol. In this case, the baud rate
for the B S protocol is set to 9600 baud. If the baud rate is set unequal to “---”, the odbus protocol with
configurable baud rate is activated.
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Function
2.3.15 Measuring and response ti es
The measuring time is the period essential for the detection of the measured value. The measuring time is
reflected in the operating time tae. For the insulation resistance measured value, it is mainly determined by the
necessary measuring pulse duration, which depends on the insulation resistance RF and the system leakage
capacitance Ce of the system to be monitored. The measuring pulse is generated by the measuring pulse
generator integrated in the ISOMETER®. The measuring times for Ce, UL1e, UL2e and R % are synchronous.
System disturbances may lead to extended measuring times. In contrast, the time for the system voltage
measurement Un is independent and considerably shorter.
Operating ti e tae
The operating time tae is the time required by the ISOMETER® to determine the measured value. The insulation
resistance measured value depends on the insulation resistance RF and the system leakage capacitance Ce.
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 ti e 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-up delay t
After connecting the supply voltage US, the alarm output is suppressed for the time set in parameter
“t” (0…10 s).
2.3.16 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.
2.3.17 External test/reset 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
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ISOMETER® iso HA425HV
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.
If coupled with AGH421-1, the activation of stop mode via the interface command disconnects the ISOMETER®
from the monitored network.
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.
2.3.18 History e ory 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 25 can be saved.
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Installation, connection and commissioning
3 Installation, connection and co issioning
3.1 Di ensions
36
93
74.5
90 45 70.5
47.5
31.1
Figure: Dimension diagram (in mm)
3.2 Installation
CAUTION Property damage due to heat
When operating on system voltages Un > 800 V, the housing of the AGH can become hotter than 60 °C.
•Mount AGH with 30 mm lateral clearance to adjacent devices.
Figure: DIN rail mounting (left) or screw mounting (right)
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.
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ISOMETER® iso HA425HV
For details about the required conductor cross sections, refer to chapter “Technical data”, page 42.
Wiring diagra legend:
Terminal Connections
A1, A2 Connection to the suppl voltage Us via fuse:
If supplied from an IT s stem, both lines have to be protected b a fuse.*
E, E, KE Connect each terminal separatel to PE:
Use the same wire cross section as for “A1”, “A2”.
L1/+, L2/– Connection to IT s stem 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 rela “K1”
11, 24 Connection to alarm rela “K2”
A, B RS-485 communication interface with selectable terminating resistance
* For U and CSA applications:
Feed the supply voltage US via 5 A back-up fuses.
For U applications:
Only use 60/75 °C copper lines.
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Installation, connection and commissioning
Wiring diagra
Figure: Wiring diagram
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