LINETRAXX® MRCDB300 series

The AC/DC sensitive MRCDB300 device series is used as additional protection (protection against indirect contact) in earthed systems (TN and TT systems) in which AC or DC fault currents may occur.

Part of these systems are particularly loads containing six-pulse rectifiers or one-way rectifiers with smoothing, such as converters, battery chargers, construction site equipment with frequency-controlled drives. When the response value IΔn2 (alarm) is reached, the output relays K1 and K2 switch.

By using an MRCDB300 module and a switching element with isolating properties, the device combination fulfils the requirements of IEC 60947-2 Annex M for an MRCD protective device.

The application is specifically intended for protection goals such as protection of persons, fire protection and plant protection. The switching element must not exceed a switch-off time of 20 ms.

The residual current monitoring modules each consist of the MRCDB300 evaluation electronics and a CTBC20(P)…210(P) series measuring current transformer core. To assemble a complete module, both the electronics and a measuring current transformer core are required; if ordered separately, these two components must then be plugged together and calibrated during commissioning.

The CTBC20P…210P series measuring current transformers feature an integrated magnetic shield and are suitable for applications with high load currents or inrush currents.

Questions? Contact us!

MRCDB300-Serie
MRCDB300-Serie

The AC/DC sensitive MRCDB300 device series is used as additional protection (protection against indirect contact) in earthed systems (TN and TT systems) in which AC or DC fault currents may occur.

Part of these systems are particularly loads containing six-pulse rectifiers or one-way rectifiers with smoothing, such as converters, battery chargers, construction site equipment with frequency-controlled drives. When the response value IΔn2 (alarm) is reached, the output relays K1 and K2 switch.

By using an MRCDB300 module and a switching element with isolating properties, the device combination fulfils the requirements of IEC 60947-2 Annex M for an MRCD protective device.

The application is specifically intended for protection goals such as protection of persons, fire protection and plant protection. The switching element must not exceed a switch-off time of 20 ms.

The residual current monitoring modules each consist of the MRCDB300 evaluation electronics and a CTBC20(P)…210(P) series measuring current transformer core. To assemble a complete module, both the electronics and a measuring current transformer core are required; if ordered separately, these two components must then be plugged together and calibrated during commissioning.

The CTBC20P…210P series measuring current transformers feature an integrated magnetic shield and are suitable for applications with high load currents or inrush currents.

Questions? Contact us!

Features

  • Structure of a protective device in accordance with IEC 60947-2 Annex M in combination with a circuit breaker providing isolating properties
  • Monitoring of the connected circuit breaker by means of contact feedback
  • RS-485 interface with Modbus RTU (reading out measured values/setting parameters)
  • Integrated switching outputs with two changeover contacts K1 and K2 (galvanically isolated)
  • Fulfils the protection goals protection of persons, fire protection and plant protection (depending on the variant)
  • Frequency range DC…100 kHz
  • Combined test and reset button
  • Multicolour LED indicating operation, exceeded response value, disturbances and status messages
  • AC/DC sensitive type B measured value acquisition acc. to IEC 60755
  • AC/DC sensitive type B+ measured value acquisition acc. to VDE 0664-400
  • Exchangeable electronic enclosure without mechanical separation of the primary conductors
  • Extension/retrofitting or modification of functionalities in case of changed monitoring requirements
  • Insensitive to load currents due to full magnetic shield (CTBC20P…210P only)
  • Connection monitoring of the measuring current transformer with cyclical test current
  • Use of all MRCDB300 for all CTBC… measuring current transformer sizes
  • Supply voltage DC 24 V

Applications

  • for MRCD applications

LINETRAXX® MRCDB300 series Variant(s)

Composition of an MRCD modue:
Electronic module + Measuring current transformers = MRCD modul

Electronic module

TypeSupply voltage USVariantArt. No.
MRCDB301DC 24 V (19.2…28,8 V)Protection of personsB74043120
MRCDB302DC 24 V (19.2…28,8 V)Fire protectionB74043121
MRCDB303DC 24 V (19.2…28,8 V)Protection of persons, fire protection and plant protection (freely configurable)B74043122
MRCDB305DC 24 V (19,2…28,8 V)Protection of persons for applications with pulsed,
very high peak load currents (> 1 kA for < 1 s), e.g. welding applications
B74043125

Required terminals are included in the scope of delivery.

Measuring current transformers

TypeInternal diameterArt. No.
CTBC2020 mmB98120001
CTBC20P20 mmB98120002
CTBC3535 mmB98120003
CTBC35P35 mmB98120004
CTBC6060 mmB98120005
CTBC60P60 mmB98120006
CTBC120120 mmB98120007
CTBC120P120 mmB98120020
CTBC210210 mmB98120008
CTBC210P210 mmB98120021

P = full magnetic shield

Optional Accessories for LINETRAXX® MRCDB300 series

Accessories

DescriptionArt. No.
Interface converter USB to RS-485B95012045
Terminal block for MRCD module*B74043124
Snap-on mounting for CTBC20 and CTBC20P*B91080111
Snap-on mounting for CTBC35 and CTBC35P*B91080112

* Included in scope of delivery

Voltage supply

Typmax. connected current transformersArt. No.
STEP-PS/1 AC/24 DC/1.7514B94053111
STEP-PS/1 AC/24 DC/4.234B94053112

Downloads for LINETRAXX® MRCDB300 series

NameCategorySizeLanguageTimestampD-/B-Number
UKCA - MRCDB3xx Declarations of Conformity 121.4 KB 2024/04/2525.04.2024
UKCA - CTxx Declarations of Conformity 132.5 KB 2024/09/2323.09.2024
TÜV NORD - AGH150x, CTACx, CTBCx, EDS44x, CTUB10x, MRCDB30x and RCMB30x Certificates 408.6 KB EN2023/10/1111.10.2023
TÜV NORD - AGH150x, CTACx, CTBCx, EDS44x, CTUB10x, MRCDB30x und RCMB30x Certificates 428.8 KB DE2023/10/1111.10.2023
MRCDB30x CE Declarations of conformity 87.4 KB 2024/04/2525.04.2024
CTxx CE Declarations of conformity 100.1 KB 2024/09/2323.09.2024
MRCDB300-Serie Datasheets 5.1 MB DE2024/07/2222.07.2024D00343
MRCDB300 series Datasheets 5.1 MB EN2024/07/2222.07.2024D00343
MRCDB300-Serie Quickstarts 1.3 MB DE2024/07/2222.07.2024D00343
MRCDB300 series Quickstarts 1.3 MB EN2024/07/2222.07.2024D00343
MRCDB300-Serie Manuals 6.8 MB DE2024/07/2222.07.2024D00343
MRCDB300 series Manuals 6.8 MB EN2024/07/2222.07.2024D00343
MRCDB300 série Datasheets 893.6 KB FR2021/08/2525.08.2021D00343
Modulares Fehlerstromgerät MRCD Flyer 96.6 KB DE2021/05/1818.05.2021
Modular Residual Current Device (MRCD) Flyer 96.3 KB EN2021/05/1818.05.2021
Dispositivo de Corriente Residual Modular MRCD Flyer 98.2 KB ES2021/05/1818.05.2021
Dispositivo differenziale separato a toroide esterno MRCD Flyer 115.1 KB IT2021/05/1818.05.2021
MRCDB300 serie Datasheets 891.7 KB ES2022/06/0909.06.2022D00343
CTBC-Serie Manuals 543.1 KB DE2023/11/1616.11.2023D00336
CTBC series Manuals 538.3 KB EN2023/11/1616.11.2023D00336