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  • Increased electrical safety
  • Quicker fault location
  • Improved system reliability
  • Reduced financial penalties
  • Reduced down time

The Rail Signalling (RS3) integrated insulation monitoring and earth fault location equipment provides proven protection for railway electrical systems and equipment up to AC650V.

The RS3 system continually monitors insulation values to show real time status of the power system. When the insulation value (IR) drops the system records the fault and puts a test current signal or pulse into the system which is pulled to earth at the point where a fault exists.

The RS3 has been superseded by the new and improved rail signalling protection system RS4 that was launched at Railtex, 14th - 16th May 2019.

This advanced and upgraded system has increased sensitivity, improving first fault location from 20K to 100KΩ. This allows maintenance teams to respond more effectively, further enhancing safety and reducing downtime to signal power systems.

The RS4 is available in three variants to comply with Tiers 1, 2 and 3 of Network Rail’s Insulation Monitoring and Fault Location standard NR/L2/SIGELP/27725.

RS4 Tier 3 provides overall insulation resistance measurements, as well as feeder level fault location of the system.

Tier 2 compliance is achieved by the use of additional system components to enable complex individual feeder measurements.

RS4 Tier 1 is the most advanced RS4 system. It provides full insulation resistance measurement of the system, feeder and individual feeders, monitoring individual subsections of cable and functional supply points (FSP).


Click here for more information on the RS4 and its enhanced capabilities over the RS3.


Network Rail approved





More information

News: Bender UK announces new RS4 at Railtex 2017

Article: Intelligent monitoring of signalling power supplies in Great Britain


Brochure: Predict and Protect


Article: Arrive safely on time



 Learn how to upgrade to RS4 in our video.

  • Features
  • Applications
  • Accessories
  • Ordering information
  • Downloads
  • Integrated insulation monitoring and earth fault location equipment provides proven protection for railway electrical systems and equipment
  • Incorporates GSM-enabled data logger equipped for real time direct communication with the Intelligent Infrastructure
  • Immediately identifies earth leakage faults in the power system arising from damaged cables, faulty connections, breaks in insulation, and rodent damage.
  • Portable earth fault location system pinpoints location for maintenance teams
  • Delivers enhanced reliability and simplified installation and commissioning.
  • Facilitates planned maintenance interventions
  • Dual adjustable insulation alarms – early warning and earth fault.
  • Standardised for use across Network Rail installations
  • Supplied in self-contained windowed cabinet, tested and ready for ‘plug and play’ installation and commissioning alongside existing power infrastructure systems up to AC650V.
  • Integral automatic and manual test facility
  • RS3 is supplied in a composite wall mount control panel with 4 mounting brackets
  • Lockable front hinged door with viewing window
  • Dimensions 600mm high x 400mm wide x 260mm deep
  • Weight 25Kg
  • Also available as a chassis mount solution
  • Rail signalling, relay rooms and trackside locations


Mandatory accessories for RS3

Bender Part No W1-S35Network Rail PADs no
Solid Core Current Transducer 35 mm0086/011087
Split Core Current Transducer 50 mm x 80 mm0086/011096

Variants of RS3

Bender Part NoNetwork Rail PADs no
RS3 Chassis0086/000105
RS3/1 – Enclosure0086/000109

Downloads for RS3



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