Bender A-ISOMETER IRDH275, A-ISOMETER IRDH275B Operating Manual
Operating Manual
A-ISOMETER® IRDH275
Power in electrical safety
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.: +49 6401-807-0
Fax: +49 6401-807-259
E-mail: info@bender-de.com
Web: http://www.bender-de.com
© Dipl.-Ing. W. Ben der GmbH & Co . KG
All rights reserved.
Reprinting only with permission
of the publisher.
Subject to change!
Table of Contents
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
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Table of Contents
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
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Table of Contents
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
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TGH1361en/11.2009
1. Safety information
1.1 Use for the intended purpose
The A-ISOMETER® is intended for:
z monitoring 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
z compliance with all information in the operating instructions, and
z compliance with test intervals.
As a basic principle, our "General conditions of Sale and Delivery" shall apply. 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:
z Use of the A-ISOMETER® other than for the intended purpose
z Incorrect assembly or installation, commissioning, operation and mainte-
nance of
the A-ISOMETER®.
z Failure to comply with the information in the operating instructions regarding
transport, commissioning, operation and maintenance of the A-ISOMETER®.
z Unauthorized structural modifications to the A-ISOMETER®.
z Failure to comply with the technical data
z Improperly executed repairs, and the use spare parts or accessories which are
not recommended by the manufacturer.
z Cases of disaster and force majeure
z Assembly and installation with device combinations not recommended.
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Safety information
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 information 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 damage 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:
z for the purpose for which it is intended
z when it is in perfect technical condition as far as safety is concerned
Any faults which may impair safety must be eliminated immediately. Impermissible 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-ISOMETER®. Warning signs must always be easily legible. Damaged or illegible
signs must be replaced immediately.
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Safety information
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 immediately.
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 attention to important information and to make it easier to find certain text passages. The following examples explain the meaning of the symbols:
TGH1361en/11.2009
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.
9
Safety information
1.4 Directions for installation
Only one insulation monitoring device may be used in each interconnected IT system.
When insulation or voltage test are to be carried out, the device shall
be isolated from the system for the test period.
The terminals and KE shall be connected by a separate wire to the protective conductor (PE). If the terminals L1, L2 of the device are connected to
a system under operation, the terminals and KE must not be disconnected 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 resistance, before starting the A-ISOMETER®.
The devices, variant -4.. are delivered with the following factory setting:
ISO SETUP:
Alarm 1 / Alarm 2
(response values)
=40 kΩ / 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)
Please check if the basic setting of the A-ISOMETER® complies with the requirements of the system to be monitored.
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.
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2. Function
2.1 Common characteristics (IRDH275 and IRDH275B)
z A-ISOMETER® for IT AC systems with galvanically connected rectifiers
and for IT DC systems (IT = unearthed systems)
z The operating range of the nominal voltage U
devices.
z Automatic adaptation to the existing system leakage capacitance
z measuring principle (European Patent: EP 0 654 673 B1)
z Two separately adjustable ranges of the response value1 kΩ...10 MΩ
(Alarm 1, Alarm 2)
z Two-line LC display
z Connection monitoring (monitoring of the measuring leads)
z Automatic device self test
z Option "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
z Memory with real-time clock to store all alarm messages with date and time
stamp.
z BMS interface (BMS protocol) for data exchange with other Bender devices
(RS485 electrically isolated).
z Internal 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 interconnected.
z Current output 0(4)...20mA (galvanically separated) in relation to the meas-
ured insulation value.
z Remote setting of certain parameters via the Internet (option; FTC470XET
additionally required)
can be extended via coupling
n
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Function
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
U
.
n
The IRDH275B can be used in combination with a control and indicating device, e.g. PRC1470 version 2 or higher, on the BMS (BMS = Bender Measuring 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 nonvolatile memory (EEPROM) after the setting is completed.
A microprocessor-controlled pulsating AC measuring voltage is superimposed on the IT system to be monitored ( measuring principle*). The
measuring cycle consists of positive and negative pulses of the same amplitude. 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 circuit. From the measured current value, the microprocessor calculates the insulation 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. System leakage capacitances do not influence the measuring accuracy.
If the reading is below the selected response values Alarm 1/Alarm 2, the associated 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 insulation faults, the faulty supply line is indicated). If the terminals R1/R2 are
bridged (external RESET button [NC contact] or wire bridge), the fault indication will be stored. Pressing the RESET button, resets the insulation fault
12
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Function
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 selecting the sub menu Memory: on/off.
The connections for external kΩ display 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 automatically. 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!" appears 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 malfunction 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 selected, the alarm relays do not switch.
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Error message Meaning Steps to be taken
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
1. Check wiring of terminal and KE to
earth (PE)
2. Press TEST button
3. Switch the supply voltage off and on
1. Press TEST button
2. Switch the supply voltage off and on
3. Contact BENDER
System connection?
Connection PE?
Device error x
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.
No low-resistance
connection of terminals L1, L2, L3
to the IT system
No low-resistance
connection of the
terminals and
KE to earth (PE)
Internal device
error
Function
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Function
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 functions. At first, the correct time and date must be set in the menu "ISO ADVANCED". 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 systems 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 measuring function is stopped and the message "STANDBY" appears on the display. 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-
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15
Function
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 ringtype 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)
16
Addr. 1
PE PE
F1/F2
IRDH275B
F1/F2
IRDH275B
G
Addr. 2
G
IT system 1 IT system 2
G
G
IT system 3IT system 4
IRDH275B
PE PE
Addr. 4
F1/F2
F1/F2
IRDH275B
Addr. 3
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Function
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 prevented that the A-ISOMETERs® disturb each other in interconnected systems. 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)
G
G
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IRDH275B
Addr. 1
IRDH275B
PE PE
IT system 1 IT system 2
IT system 3IT system 4
IRDH275B
Addr. 4
IRDH275B
PE PE
Addr. 2
G
G
Addr. 3
17
Function
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3. Commissioning flow chart (threepart)
Due to limitations of space, the three-part flow chart begins on the next page.
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Commissioning flow chart (threepart)
The encircled figures in the flow chart correspond to the figures in the legend to the wiring diagram.
Commissioning of the A-ISOMETER® (1)
Is the system to be monitored an
unearthed system (IT system)?
no
The IRDH275 is not suitable for this
application( contact BENDER).
Is the maximum nominal voltage
AC 793 V
U
n
or Un DC 650 V
no
Un is too high for direct
connection. A coupling device
providing the respective voltage
range must be connected.
Deenergize the installation
before connecting the device!
yes
Device connection Optional device
The two PE connections
be connected separately to the
equipotential bonding.
The terminals L1 and L2 must be
connected to Un of the system to be monitored according to the wiring diagram.
Connect the supply voltage Us
to the terminals A1/+ and A2/-. Consider
the details indicated on the nameplate.
Recommended wire cross section of
connecting cable
single wire 0.2...4 mm
flexible 0.2... 2.5 mm
and KE must
6
2
3
4
5
1
2
2
An external kW measuring instrument
at M+/M- with a display range of
10 kW...1000 kW,
Scale centre point: 120 kW
Output current IRDH275: 0...400 mA
Output current IRDH275B: 0/4...20 mA
External TEST button (NO contact) to the
terminals T1 and T2
External RESET button (NC contact) to the
terminals R1 and R2
yes
connection
10
7
8
When using the RS485 interface, take care
that a 120 W resistor is connected at
the beginning and the end of the network.
20
11
The output contacts of the alarm relays
System fault (21-22-24)
Alarm 1 (11-12-14)
Alarm 2 (21-22-24)
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12
13
Commissioning flow chart (threepart)
Commissioning of the A-ISOMETER® (2)
Connect the supply
voltage U
Connect the voltage Un of the
IT system to be monitored
Only IRDH275B:
set the clock
S
The A-ISOMETER carries out a
self test. The display indicates
the insulation value after finishing
the measurement.
Shall the basic setting
be changed?
Alarm1 = 40 kW
Alarm2 = 10 kW
K1/K2 = N/O operation
Memory = off
no
Does one of the alarm LEDs
light up?
no
yes
yes
Select ISO SETUP
(see chapter operation and setting)
The insulation value of the system
being monitored is below the preset
response value. Change the response
value or improve the insulation
condition of the system.
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21
Commissioning of the A-ISOMETER® (3)
In order to check the proper
connection, a functional test
using a suitable resistance is
to be carried out.
Size of the resistance:
50% of the preset response
value Alarm 2.
Commissioning flow chart (threepart)
Do both alarm LEDs light up?
Did the alarm relays switch ?
yes
Remove the resistor !
Alarm LEDs extinguished ?
Did the output relays change
their position ?
yes
The IRDH275 is correctly
connected and functions reliably !
no
no
yes
Check the connecting leads !
Is voltage Un applied to the
terminals L1/L2 ?
When a coupling device is
used, is it correctly connected ?
Check the voltages with a voltmeter !
Do both alarm LEDs light ?
Did the alarm relays switch?
22
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4. Connection
4.1 Wiring
Connect the terminals A1/+ and A2/- to the supply voltage US in accordance
with IEC 60364-4-43. The connections to the supply voltage shall be provided with protective devices to afford protection in the event of a short circuit
(a 6 A fuse is recommended).
Devices for protection against short-circuit in conformity with IEC 60364-443 for the IT system coupling L1/L2 can be omitted if the wiring is carried
out in such a manner as to reduce the risk of a short-circuit to a minimum (a
short-circuit-proof and earth-fault-proof wiring is recommended).
Only one A-ISOMETER® may be connected to an external TEST or RESET
button. A galvanic parallel connection of several TEST and RESET inputs for
collective testing of A-ISOMETER®s is not permitted.
External coupling devices connected via the terminal AK cannot be switched
off via the internal coupling relays. If no coupling device is used, the terminal
AK remains free.
TGH1361en/11.2009
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