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Manual EN ISOMETER® isoUG425 Insulation monitoring device for earth fault detection in unearthed DC systems up to 120 V Software version: D0476 V2.xx isoUG425_D00220_04_M_XXEN/10.2023...
Indication of important instructions and information...............5 Signs and symbols............................5 Service and Support............................5 Training courses and seminars........................6 Delivery conditions............................6 Inspection, transport and storage......................6 Warranty and liability.............................6 Disposal of Bender devices..........................7 1.10 Safety..................................7 Function.......................8 Intended use..............................8 Device features..............................8 Function description............................8 2.3.1...
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Table of contents Operating and display elements......................18 Menu overview...............................20 Displaying measured values........................21 Setting the response values (AL)......................21 4.4.1 Setting the response values for monitoring the insulation resistance........21 4.4.2 Setting the response values for undervoltage and overvoltage..........22 4.4.3 Response values overview.........................22 Configuring fault memory, alarm relays, and interfaces (out)............22 4.5.1 Configuring the relays..........................22...
Protect from dust Temperature range Recycling RoHS directives 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 & Co. KG. isoUG425_D00220_04_M_XXEN/10.2023...
Regular face-to-face or online seminars for customers and other interested parties: www.bender.de > know-how > seminars. Delivery conditions The conditions of sale and delivery set out by Bender GmbH & Co. KG apply. These can be obtained in printed or electronic format. The following applies to software products: ‘Software clause in respect of the licensing of standard software as part of deliveries,...
ISOMETER® isoUG425 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.
• Two separately adjustable response value ranges 1…100 k (prewarning, alarm) • RS-485 (galvanically isolated) including the following protocols: – BMS (Bender measuring device interface) for the data exchange with other Bender devices – Modbus RTU – IsoData (for continuous data output) •...
ISOMETER® isoUG425 It is possible to assign the detected fault or the faulty conductor to an alarm relay via the menu. If the values R or U violate the response values activated in the “AL” menu, this will be indicated by the LEDs and relays “K1” and “K2”...
(“Err”) is signalled, “E.xx” appears on the display as an identifier for error type xx, and the LEDs “ON”/“AL1”/“AL2” flash. Please contact Bender Service, if the error occurs again after the device has been restarted or the factory settings have been restored.
ISOMETER® isoUG425 2.3.5 Alarm assignment of the alarm relays K1/K2 The notifications for “device error”, “insulation fault”, “undervoltage/overvoltage fault”, “device test” and “device start with alarm” can be assigned to the alarm relays via the “out” menu. An insulation fault is indicated by these messages: •...
Function Delay on release t The delay on release t 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 t 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 t without interruption.
The ISOMETER® uses the serial hardware interface RS-485 with the following protocols: • BMS The BMS protocol is an essential component of the Bender measuring device interface (BMS bus protocol). Data transmission generally makes use of ASCII characters. • Modbus RTU Modbus RTU is an application layer messaging protocol, and it provides master/slave communication between devices that are connected via bus systems and networks.
ISOMETER® isoUG425 Connection DANGER Risk of fatal injury due to electric shock! Touching live parts of the system carries the risk of: • Risk of electrocution due to electric shock • Damage to the electrical installation • Destruction of the device Before installing the device and before working on its connections, make sure that the installation has been de-energised.
Installation, connection and commissioning Legend to wiring diagram Terminal Connections A1, A2 Connection to the supply voltage U via fuse (line protection): If supplied from an IT system, protect both lines by a fuse.* E, KE Separate connection to PE: Use same wire cross section as for “A1”, “A2”.
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ISOMETER® isoUG425 Check the functionality by a real insulation fault. Use a suitable resistor to check the ISOMETER® against earth in the system being monitored. isoUG425_D00220_04_M_XXEN/10.2023...
Operation Operation Operating and display elements Device front Operating elements Function Power LED AL1 AL2 Alarm LEDs (For codes see “Assigning the alarm messages to the relays”, page 22.) Up and down buttons – For navigating up or down in the menu settings.
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ISOMETER® isoUG425 Display Display elements Function System voltage U Insulation resistance R System leakage capacitance C Monitored conductors L1 L2 L1 = L+ L2 = L– Voltage type DC Pulse symbol: error-free measured value update Voltage type AC °C Measured values and units μ...
Operation Menu overview Measurement display Menu selection Parameter selection > < 1.5 s > > . . . 1.5 s 1.5 s < t > 5 min < > 1.5 s R [k ] Password (optional) C [µF] U L1 L2 [V] U L1 [V] <...
ISOMETER® isoUG425 Displaying measured values Overview Display Description Insulation resistance R ✓ 1 k … 1 M System voltage U (L+ - L–) ✓ nRMS U L1 L2 = ~V 0…150 V System voltage U (L+ - L–) ✓ U L1 L2 = V DC 0…150 V Residual voltage U (L+ - PE)
Operation 4.4.2 Setting the response values for undervoltage and overvoltage How to proceed Open menu “AL”. Select parameter “U<” for undervoltage or parameter “U>” for overvoltage. Set value and confirm with Enter. 4.4.3 Response values overview Display Activation Setting value Description Range Prewarning value R...
Operation 4.5.4 Configuring interface Display Setting value Description Range Adr = 0 deactivates BMS as well as Modbus 0 / 3…90 Bus Adr. and activates isoData with continuous data output (115k2, 8E1) “---”: BMS bus (9k6, 7E1) Adr 1 “---” ) Baud rate 1.2k…115k “1.2k”...
1...50 capacitance C S.Ct Device test at device start Restore factory settings For Bender Service only FAC Factory settings Customer settings Reset to factory settings All settings with the exception of the interface parameters are reset to the factory settings.
Data access via RS-485 interface Data access via RS-485 interface Data access using the BMS protocol The BMS protocol is an essential component of the Bender measuring device interface (BMS bus protocol). Data transmission generally makes use of ASCII characters. BMS channel no.
ISOMETER® isoUG425 Command of the master to the ISOMETER® In the following example, the master of the ISOMETER® requests the content of register 1003 using address 3. The register contains the channel description of measuring channel 1. Byte Name Example Byte 0 ISOMETER®...
Data access via RS-485 interface Response of the ISOMETER® to the master Byte Name Example Byte 0 ISOMETER® Modbus address 0x03 Byte 1 Function code 0x10 Byte 2, 3 Start register 0x0BBB Byte 4, 5 Number of registers 0x0001 Byte 6, 7 CRC16 checksum 0x722A 5.2.3...
ISOMETER® isoUG425 Modbus register assignment 5.3.1 Modbus measured value registers Depending on the device condition, the information in the registers is the measured value without alarm, the measured value with alarm 1, the measured value with alarm 2, or the device error. For more information see , page 30.
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Data access via RS-485 interface 5.3.1.2 Float = Floating point value of the channels Representation of the bit order for processing analogue measured values according to IEEE 754 Word 0x00 0x01 Byte HiByte LoByte HiByte LoByte 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 exponent mantissa sign...
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ISOMETER® isoUG425 5.3.1.4 R&U = Range and unit Meaning Unit Invalid (init) No unit Baud °C °F Second Minute Hour Month Range of validity Actual value The actual value is lower The actual value is higher Invalid value • Bits 0 to 4: coding for the unit •...
Data access via RS-485 interface 5.3.1.5 Channel descriptions Value Description of measured value / message Comments 1 (0x01) Insulation fault 71 (0x47) Insulation fault Insulation resistance R 76 (0x4C) Voltage Measured value in V 77 (0x4D) Undervoltage 78 (0x4E) Overvoltage 82 (0x52) Capacitance Measured value in F...
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ISOMETER® isoUG425 Register Property Description Format Unit Value range 3011 Alarm value overvoltage DC “U>” UINT 16 1/10 V U< … 1440 0 = off Memory function for alarm 3012 UINT 16 messages (fault memory) “M” 1 = on 0 = n/o 3013 Operating mode of relay K1 “r1”...
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Data access via RS-485 interface Register Property Description Format Unit Value range 3027 Alarm assignment of relay K1 “r1” UINT 16 Bit 9 … Bit 1 3028 Alarm assignment of relay K2 “r2” UINT 16 Bit 9 … Bit 1 8003 Factory settings for all parameters UINT 16...
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ISOMETER® isoUG425 Display indication Meaning rx test Manually started self test rx S.AL Device start with alarm When reading: 0 Reserved When writing: any value When reading: 0 Reserved When writing: any value When reading: 0 12…15 Reserved When writing: any value 5.3.2.3 Device name The data format of the device name consists of ten Words with two ASCII characters each.
Data access via RS-485 interface IsoData data string In IsoData mode the ISOMETER® sends the entire data string roughly once per second. Communication with the ISOMETER® in this mode is not possible and no additional sender may be connected via the RS-485 bus cable.
ISOMETER® isoUG425 Technical data Technical data isoUG425 ( )* = factory setting Insulation coordination acc. to IEC 60664-1/-3 Definitions Measuring circuit (IC1) L+, L– Supply circuit (IC2) A1, A2 Output circuit (IC3) 11, 14, 24 Control circuit (IC4) E, KE, T/R, A, B Rated voltage 400 V Overvoltage category...
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Technical data Supply voltage Supply voltage U AC 100…240 V DC 24…240 V Tolerance of U –30…+15 % Frequency range of U 47…63 Hz Power consumption ≤ 3 W, ≤ 9 VA Monitored IT system Nominal system voltage U DC 12…120 V Tolerance of U +20 % Measuring circuit...
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ISOMETER® isoUG425 Displays, memory Display LC display, multi-functional, not illuminated Display range measured value insulation resistance (R 1 k … 1 M Operating uncertainty R ±15 %, at least ±2 k Display range measured value system voltage (U 0…150 V (R =∞...
EU Declaration of Conformity Hereby, Bender GmbH & Co. KG declares that the device covered by the Radio Directive complies with Directive 2014/53/EU. The full text of the EU Declaration of Conformity is available at the following Internet address: https://www.bender.de/fileadmin/content/Products/CE/CEKO_isoXX425.pdf...
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