Bender A-ISOMETER IRDH275 User manual

Power in electrical safety
Operating Manual
A-ISOMETER® IRDH275
IRDH275B
Insulation monitoring device for
IT AC systems with galvanically connected
rectifiers and converters
and for IT DC systems
Software version IRDH275: D160 V1.4
Software version IRDH275B: D159 V1.4
TGH1361en/11.2009

Dipl.-Ing. W. Bender GmbH & Co. KG
Londorfer Str. 65 • 35305 Grünberg • Germany
Postfach 1161 • 35301 Grünberg • Germany
Tel.: [phone]
Fax: [phone]
E-mail: [e-mail]
Web: http://www.bender-de.com
©Dipl.-Ing. W. Bender GmbH & Co. KG
All rights reserved.
Reprinting only with permission
of the publisher.
Subject to change!

3
Table of Contents
TGH1361en/11.2009
1. Safety information .................................................................................. 7
1.1 Use for the intended purpose ............................................................................. 7
1.2 Warranty and liability ............................................................................................. 7
1.2.1 Personnel .................................................................................................................... 8
1.2.2 About the operating manual .............................................................................. 8
1.2.3 Hazards when handling the A-ISOMETER® IRDH275 .................................. 8
1.2.4 Inspection, transport and storage ..................................................................... 9
1.2.5 Note .............................................................................................................................. 9
1.3 Explanations of symbols and warnings ........................................................... 9
1.4 Directions for installation ................................................................................... 10
2. Function ................................................................................................. 11
2.1 Common characteristics (IRDH275 and IRDH275B) .................................. 11
2.2 Additional characteristics IRDH275B .............................................................. 11
2.3 Product description .............................................................................................. 12
2.4 Function .................................................................................................................... 12
2.5 Additional functions IRDH275B ........................................................................ 15
3. Commissioning flow chart (threepart) ............................................. 19
4. Connection ............................................................................................ 23
4.1 Wiring ......................................................................................................................... 23
4.2 Wiring diagrams with coupling devices ........................................................ 26
4.2.1 Connection with AGH150W-4 ........................................................................... 26
4.2.2 Connection with AGH520S ................................................................................ 27
4.2.3 Connection with AGH204S-4 ............................................................................ 28

Table of Contents
4TGH1361en/11.2009
5. Operation and setting .......................................................................... 31
5.1 Operating features and displays IRDH275(B) .............................................. 31
5.1.1 Display in the standard mode ........................................................................... 32
5.1.2 Display in the menu mode ................................................................................. 32
5.1.3 Function keys .......................................................................................................... 33
5.2 Menu structure and menu mode ................................................... 36
5.2.1 Diagram menu structure ..................................................................................... 37
5.3 Menu HISTORY INFO (IRDH275B) .................................................. 38
5.3.1 Diagram HISTORY INFO (IRDH275B) ............................................................... 39
5.4 Menu ISO SETUP:
Setting of the basic A-ISOMETER® functions ................................ 40
5.4.1 Response values Alarm 1 and Alarm 2 ........................................................... 40
5.4.2 Operating principle of the alarm relays ......................................................... 40
5.4.3 Memory setting (on/off) ...................................................................................... 42
5.4.4 Current output for external measuring instruments (IRDH275B) ........ 42
5.5 Menu ISO ADVANCED:
Setting of the extended functions ................................................ 43
5.5.1 External coupling devices (AGH: no) .............................................................. 43
5.5.2 Adaptation to the system leakage capacitance (Cemax : 150 μF) ....... 44
5.5.3 Changing the measuring principle from AMP to DC (Measure: AMP) 44
5.5.4 Setting the repetition time for automatic self tests (Autotest: 24h) ... 44
5.5.5 Setting the real-time clock (Clock) (IRDH275B) .......................................... 44
5.5.6 Setting the date (Date) (IRDH275B) ................................................................ 44
5.5.7 Specifying the starting time of the automatic self test (Test)
(IRDH275B) ............................................................................................................... 44
5.5.8 Diagram ISO ADVANCED .................................................................................... 45
5.6 Menu COM SETUP:
Setting the BMS interface .............................................................. 46
5.6.1 Bus address „Addr:“ (IRDH275B) ...................................................................... 46
5.6.2 ISOnet function (IRDH275B) .............................................................................. 46
5.6.3 ISO monitor (IRDH275B) ...................................................................................... 46
5.6.4 Diagram COM SETUP (IRDH275B) .................................................................... 47
5.7 Menu PASSWORD ........................................................................... 48
5.7.1 Activating and setting the password ............................................................. 48
5.7.2 Diagram PASSWORD ............................................................................................ 48

Table of Contents
5TGH1361en/11.2009
5.8 Menu LANGUAGE ........................................................................... 49
5.8.1 Setting the national language .......................................................................... 49
5.8.2 Diagram Language ............................................................................................... 49
5.9 Menu SERVICE ......................................................................................................... 50
5.10 Parameterization via Internet ........................................................................... 50
6. Serial interfaces ..................................................................................... 51
6.1 RS485 interface with IsoData protocol (IRDH275) ..................................... 51
6.2 RS485 interface with BMS protocol (IRDH275B) ......................................... 53
6.3 Topology RS485 network (IRDH275B) ............................................................ 54
6.3.1 Correct arrangement ............................................................................................ 54
6.3.2 Wrong arrangement ............................................................................................. 54
6.3.3 Wiring ......................................................................................................................... 54
6.4 BMS protocol (IRDH275B) ................................................................................... 55
6.4.1 BMS Master .............................................................................................................. 55
6.4.2 BMS Slave ................................................................................................................. 56
6.4.3 Commissioning of an RS485 network with BMS protocol ...................... 57
7. Technical data IRDH275(B) .................................................................. 59
7.1 Data in tabular form ............................................................................................. 59
7.2 Standards and approvals .................................................................................... 62
7.3 Characteristic curves ............................................................................................ 63
7.4 Ordering details ..................................................................................................... 70
7.4.1 A-ISOMETER® ........................................................................................................... 70
7.4.2 Coupling devices ................................................................................................... 71
7.4.3 Measuring instruments ....................................................................................... 71
7.4.4 Label for modified versions ............................................................................... 71

7
TGH1361en/11.2009
1. Safety information
1.1 Use for the intended purpose
The A-ISOMETER® is intended for:
zmonitoring the insulation resistance of IT systems
Any other use, or any use which goes beyond the foregoing, is deemed to
be use other than for the intended purpose. The BENDER companies shall
not be liable for any losses or damage arising therefrom.
Use for the intended purpose also includes
zcompliance with all information in the operating instructions, and
zcompliance with test intervals.
As a basic principle, our "General conditions of Sale and Delivery" shall ap-
ply. At the latest, these shall be available to the operator when the contract
is concluded.
1.2 Warranty and liability
Warranty and liability claims in cases of damage to persons and property
shall be excluded if they are attributable to one or more of the following
causes:
zUse of the A-ISOMETER® other than for the intended purpose
zIncorrect assembly or installation, commissioning, operation and mainte-
nance of
the A-ISOMETER®.
zFailure to comply with the information in the operating instructions regarding
transport, commissioning, operation and maintenance of the A-ISOMETER®.
zUnauthorized structural modifications to the A-ISOMETER®.
zFailure to comply with the technical data
zImproperly executed repairs, and the use spare parts or accessories which are
not recommended by the manufacturer.
zCases of disaster and force majeure
zAssembly and installation with device combinations not recommended.

Safety information
8TGH1361en/11.2009
This operating manual, especially the safety information, must be observed
above all by personnel who work on the A-ISOMETER®.
In addition, the rules and regulations that apply for accident prevention at
the place of use must be observed.
1.2.1 Personnel
Only appropriately qualified staff may work on the A-ISOMETER®. Qualified
means familiar with the installation, commissioning and operation of the
product and with training appropriate to the work.
Personnel must have read and understood the safety section and warning in-
formation in this operating manual.
1.2.2 About the operating manual
This operating manual has been compiled with the greatest possible care.
Nevertheless, errors and mistakes cannot be entirely ruled out. The BENDER
companies assume no liability whatsoever for any injury to persons or dam-
age to property which may be sustained as a result of faults or errors in this
operating manual.
1.2.3 Hazards when handling the A-ISOMETER®IRDH275
The A-ISOMETER®IRDH275 is constructed according to the state-of-the-art
and recognized technical safety rules. Nevertheless, when it is being used,
hazards may occur to the life and limb of the user or third parties, or there
may be adverse effects on the A-ISOMETER®or on other valuable property.
The A-ISOMETER®must only be used:
zfor the purpose for which it is intended
zwhen it is in perfect technical condition as far as safety is concerned
Any faults which may impair safety must be eliminated immediately. Imper-
missible modifications and the use of spare parts and additional devices
which are not sold or recommended by the manufacturer of the devices may
cause fires, electric shocks and injuries.
Unauthorized persons must not have access to or contact with the A-ISOME-
TER®. Warning signs must always be easily legible. Damaged or illegible
signs must be replaced immediately.

Safety information
9
TGH1361en/11.2009
1.2.4 Inspection, transport and storage
Inspect the dispatch packaging and equipment packaging for damage, and
compare the contents of the package with the delivery documents. In the
event of damage in transit, please inform the BENDER company immediate-
ly.
The devices must only be stored in areas protected from dust, damp and
spray or dripping water, and in which the specified storage temperatures are
maintained.
1.2.5 Note
Make sure that the operating voltage is correct!
Prior to insulation and voltage tests, the A-ISOMETER®must be disconnected
from the power system for the duration of these tests.
In order to check the proper connection of the device, it is recommended to
carry out a functional test.
Make sure that the basic settings meet the requirements of the system.
Children and unauthorized persons must not have access to or contact with
the A-ISOMETER®.
1.3 Explanations of symbols and warnings
The following symbols are used in BENDER documentation to draw atten-
tion to important information and to make it easier to find certain text pas-
sages. The following examples explain the meaning of the symbols:
The "Attention" symbol is used to draw attention to information
warning employees of hazardous situations.
Information you should know for correct handling of the product is
marked with the "Info" symbol.

Safety information
10 TGH1361en/11.2009
1.4 Directions for installation
The terminals and KE shall be connected by a separate wire to the pro-
tective conductor (PE). If the terminals L1, L2 of the device are connected to
a system under operation, the terminals and KE must not be disconnect-
ed from the protective conductor (PE).
In order to check the proper connection of the device, it is recommended to
carry out a functional test using a genuine earth fault, e.g. via a suitable re-
sistance, before starting the A-ISOMETER®.
The devices, variant -4.. are delivered with the following factory setting:
Please check if the basic setting of the A-ISOMETER®complies with the re-
quirements of the system to be monitored.
Only one insulation monitoring device may be used in each intercon-
nected IT system.
When insulation or voltage test are to be carried out, the device shall
be isolated from the system for the test period.
ISO SETUP: Alarm 1 / Alarm 2
(response values)
=40kΩ/ 10 kΩ
ISO SETUP: Operating principle K1/K2 = N/O operation
ISO SETUP: Memory = off
ISO ADVANCED: System leakage capacitance = 150 μF
COM SETUP: Bus address = 3 (slave)
When an AC system includes galvanically connected DC circuits, the
following shall be considered:
Insulation faults in DC circuits can only be monitored correctly when
the rectifiers carry a continuous load of 5...10 mA.

11
TGH1361en/11.2009
2. Function
2.1 Common characteristics (IRDH275 and IRDH275B)
zA-ISOMETER® for IT AC systems with galvanically connected rectifiers
and for IT DC systems (IT = unearthed systems)
zThe operating range of the nominal voltage Uncan be extended via coupling
devices.
zAutomatic adaptation to the existing system leakage capacitance
zmeasuring principle (European Patent: EP 0 654 673 B1)
zTwo separately adjustable ranges of the response value1 kΩ...10 MΩ
(Alarm 1, Alarm 2)
zTwo-line LC display
zConnection monitoring (monitoring of the measuring leads)
zAutomatic device self test
zOption "W":
This option provides: improved shock and vibration resistance for use in ships,
on rolling stock and in seismic environment.
2.2 Additional characteristics IRDH275B
zMemory with real-time clock to store all alarm messages with date and time
stamp.
zBMS interface (BMS protocol) for data exchange with other Bender devices
(RS485 electrically isolated).
zInternal disconnection of the A-ISOMETER from the IT system to be monitored
(using a control signal; terminals F1/F2) , e.g. if several A-ISOMETERs® are inter-
connected.
zCurrent output 0(4)...20mA (galvanically separated) in relation to the meas-
ured insulation value.
zRemote setting of certain parameters via the Internet (option; FTC470XET
additionally required)

Function
12 TGH1361en/11.2009
2.3 Product description
The A-ISOMETER® type IRDH275 monitors the insulation resistance of IT
systems. It is suitable for universal use in 3(N)AC, AC/DC and DC systems.
AC systems may include extensive DC supplied loads, such as converters or
thyristor-controlled DC drives. The device automatically adapts itself to the
existing system leakage capacitance.
Suitable coupling devices are available to extend the nominal voltage range
Un.
The IRDH275B can be used in combination with a control and indicating de-
vice, e.g. PRC1470 version 2 or higher, on the BMS (BMS = Bender Measur-
ing Device Interface) bus.
2.4 Function
The A-ISOMETER® IRDH275 is connected between the unearthed system (IT
system) and the protective conductor (PE).
The response values and other function parameters are set via the function
keys. The parameters are indicated on the LC display and are stored in a non-
volatile memory (EEPROM) after the setting is completed.
A microprocessor-controlled pulsating AC measuring voltage is superim-
posed on the IT system to be monitored ( measuring principle*). The
measuring cycle consists of positive and negative pulses of the same ampli-
tude. The period of these pulses depends on the respective system leakage
capacitances and the insulation resistances of the IT system to be monitored.
An insulation fault between the IT system and earth closes the measuring cir-
cuit. From the measured current value, the microprocessor calculates the in-
sulation resistance which is indicated on the LC display or the external kΩ
measuring instrument.
The measuring time is determined by the system leakage capacitances, the
insulation resistance, and the system-related interference disturbances. Sys-
tem leakage capacitances do not influence the measuring accuracy.
If the reading is below the selected response values Alarm 1/Alarm 2, the as-
sociated alarm relays respond and the alarm LEDs "Alarm 1/2“ light up and
the measuring value is indicated on the LC display (in the event of DC insu-
lation faults, the faulty supply line is indicated). If the terminals R1/R2 are
bridged (external RESET button [NC contact] or wire bridge), the fault indi-
cation will be stored. Pressing the RESET button, resets the insulation fault

Function
13
TGH1361en/11.2009
message, provided that the currently displayed insulation resistance is at
least 25% above the actual response value when the reset is carried out. The
fault memory behaviour can also be set in the "ISO SETUP" menu, by select-
ing the sub menu Memory: on/off.
The connections for external kΩdisplay supplied by the current output
0...400 µA or 0/4...20 mA (IRDH275B) at M+/M- are galvanically isolated.
*) measuring principle "adaptive measuring pulse", a measuring
principle developed by BENDER (European Patent: EP 0 654 673 B1).
Self test
A self test can be carried out manually using the TEST button or automatical-
ly. In order to guarantee high functional reliability, the A-ISOMETER®
IRDH275 provides comprehensive self test functions. After switching the
supply voltage on, all internal measuring functions, the components of the
process control such as data and parameter memory as well as system and
earth connections are checked using the self test functions. The progress of
the self test is indicated on the display by a bar graph. Depending on the
conditions in the IT system to be monitored, the self test is running for
15...20 seconds, then the message "Test ok!" appears on the LC display for
approximately 2 seconds. Then the device returns to normal measuring
mode and the current measuring value is displayed after the expiry of the
measuring time.
When a device error or connection fault is found, the message "!Error!" ap-
pears on the display, the device fault LED lights up, the relay K2 (21-22-24)
switches and the respective fault message (see table) is indicated. If such a
device fault occurs, a self test is started again every minute. If no more mal-
function is detected, the fault message is deleted automatically and the
device fault LED extinguishes.
During operation, the self test function can be started by pressing the TEST
button (internal or external). The self test can also be started automatically
every hour or every 24 hours by selecting "ISO ADVANCED: Autotest" menu.
The alarm relays Alarm1/2 only switch after starting the self test function by
pressing the TEST button, that means if an automatic self test has been se-
lected, the alarm relays do not switch.

Function
14 TGH1361en/11.2009
Error message Meaning Steps to be taken
System connection?
No low-resistance
connection of ter-
minals L1, L2, L3
to the IT system
1. Check the wiring of terminal L1, L2 to
the IT system
2. Press the test button
3. Switch the supply voltage off and on.
4. Check the fuses
Connection PE?
No low-resistance
connection of the
terminals and
KE to earth (PE)
1. Check wiring of terminal and KE to
earth (PE)
2. Press TEST button
3. Switch the supply voltage off and on
Device error x Internal device
error
1. Press TEST button
2. Switch the supply voltage off and on
3. Contact BENDER
If the on/off switching of the supply voltage is not possible for technical
reasons, a RESET of the process control can be carried out by pressing
the "ESC“, "RESET“ and "MENU“ key.

Function
15
TGH1361en/11.2009
2.5 Additional functions IRDH275B
Current output for external measuring instrument
The current output of IRDH275B provides 0(4)...20 mA. The current output
is galvanically isolated from the device electronics and the RS485 interface.
The ISO SETUP menu, on page 43, allows to switch over between 0...20 mA
and 4...20 mA.
Real-time clock
The real-time clock serves as a time base for the memory and self test func-
tions. At first, the correct time and date must be set in the menu "ISO AD-
VANCED". If time and date are not set, a „C“ (clock) is flashing in the
standard display. In the event of a supply voltage failure, time and date will
be stored for at least thirty days.
If the 24 h test is activated in the "ISO ADVANCED" menu, a special time of
day can be selected for the execution of the self test in the menu "TEST:
12:00". Then a self test will be started automatically once a day exactly at the
preset time. If the 1 h auto test has been selected, the self test is automatically
carried out every full hour.
Interconnected IT systems
When using A-ISOMETERs® in IT systems, make sure that only one active
A-ISOMETER® is connected in each interconnected system. If IT systems are
interconnected via coupling switches, make sure that A-ISOMETERs® not
currently used are disconnected and deactivated via a control system. IT sys-
tems coupled via diodes or capacitances may also influence the insulation
monitoring process. Hence, also in this case a central control of the different
A-ISOMETERs® is required.
Function input F1/F2 for connection or disconnection of
IT systems being monitored
The A-ISOMETER® can be disconnected from the IT system and set to
STANDBY mode with the function input F1/F2. If the input F1/F2 is bridged,
the connections L1/L2 are switched off via internal coupling relays, the meas-
uring function is stopped and the message "STANDBY" appears on the dis-
play. Software version 1.4 or higher does not indicate the measured
insulation resistance during the disconnection, but indicates the value
> 10 MΩ. Furthermore, the alarm relays and alarm LEDs no longer provide
alarm messages. After opening the function input F1/F2, the connection to
the IT system will be restored and a completely new measuring cycle for in-

Function
16 TGH1361en/11.2009
sulation monitoring is started.
With this function, selective disconnection of an IRDH275 in interconnected
IT systems can be carried out via auxiliary contacts of the respective coupling
switch. One coupling switch each in a line-type or ring-type arrangement can
deactivate a subsequent IRDH275. This arrangement guarantees that only
one A-ISOMETER® is active in each galvanically connected system. In a ring-
type arrangement with all coupling switches closed, it can be assumed that
all A-ISOMETER®s are deactivated. In order to prevent this, a BMS Master
(IRDH275B BMS address 1) monitors the condition of the function input F1/
F2 of all slave A-ISOMETERs®. When all slave A-ISOMETERs® are in the
STANDBY mode, the insulation monitoring function of the Master
A-ISOMETER® and hence the function input F1/F2 of the Master are without
function in this mode.
Details are shown in the graphic below.
BMS bus (A/B, RS485)
F /F2
PE PE
PE PE
IT system 1 IT system 2
IT system 3IT system 4
G
G
G
G
Addr. Addr. 2
Addr. 4 Addr. 3
IRDH275B IRDH275B
IRDH275B IRDH275B
F /F2
F /F2 F /F2

Function
17
TGH1361en/11.2009
ISOnet Function (COM SETUP)
Select "ISOnet=ON" from the COM SETUP menu to activate this function.
This function is a type of scanning function. The BMS Master activated via
the ISOnet function controls the ISOnet slave devices via the BMS bus. Once
an A-ISOMETER® has finished its measurement cycle, the authorization for
measuring the insulation resistance is passed on from the ISOnet Master to
the next slave. While an A-ISOMETER® is carrying out a measurement all
other A-ISOMETERs® are in the STANDBY mode. In this way it can be pre-
vented that the A-ISOMETERs® disturb each other in interconnected sys-
tems. In comparison to the solution coupling switches and function input F1/
F2, the response time is prolonged, since no continuous measurement takes
place. The advantage is that no auxiliary contacts of a coupling switch are
required. Furthermore, this solution is ideally suited for capacitive IT systems
or IT systems connected via diodes.
An ISOnet slave checks whether there is a Master available in the network.
If there is no Master available, the fault message "ISOnet Master?" appears on
the display. When the ISOnet function is activated, the function input F1/F2
will be disconnected.
BMS bus (A/B, RS485)
PE PE
PE PE
IT system 1 IT system 2
IT system 3IT system 4
G
G
G
G
Addr. Addr. 2
Addr. 4 Addr. 3
IRDH275B IRDH275B
IRDH275B IRDH275B

Function
18 TGH1361en/11.2009

19
TGH1361en/11.2009
3. Commissioning flow chart (threepart)
Due to limitations of space, the three-part flow chart begins on the next page.

Commissioning flow chart (threepart)
20 TGH1361en/11.2009
The encircled figures in the flow chart correspond to the figures in the leg-
end to the wiring diagram.
Commissioning of the A-ISOMETER® (1)
Is the system to be monitored an
unearthed system (IT system)?
The IRDH275 is not suitable or this
application( contact BENDER).
Un is too high or direct
connection. A coupling device
providing the respective voltage
range must be connected.
Device connection Optional device
connection
no
no
yes
The terminals L1 and L2 must be
connected to Un o the system to be moni-
tored according to the wiring diagram.
An external kW measuring instrument
at M+/M- with a display range o
10 kW...1000 kW,
Scale centre point: 120 kW
Output current IRDH275: 0...400 mA
Output current IRDH275B: 0/4...20 mA
Connect the supply voltage Us
to the terminals A1/+ and A2/-. Consider
the details indicated on the nameplate.
External TEST button (NO contact) to the
terminals T1 and T2
External RESET button (NC contact) to the
terminals R1 and R2
The output contacts o the alarm relays
System ault (21-22-24)
Alarm 1 (11-12-14)
Alarm 2 (21-22-24)
When using the RS485 inter ace, take care
that a 120 W resistor is connected at
the beginning and the end o the network.
13
12
11
7
8
10
Deenergize the installation
before connecting the device!
Recommended wire cross section o
connecting cable
single wire 0.2...4 mm2
lexible 0.2... 2.5 mm2
Is the maximum nominal voltage
Un AC 793 V
or Un DC 650 V
yes
The two PE connections and KE must
be connected separately to the
equipotential bonding.
6
2
3
4
5
1