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RS4 Tier 3

RS4 Tier 3

  • Tier 3 RS4 is the enhanced rail signalling protection system
  • Network Rail Certificate of Acceptance PA05/04750
  • For compliance with NR/L2/SIGELP/27725 Tier 3
  • Improved fault location from 20KΩ to 100KΩ
  • Cost effective and easy to upgrade to legacy equipment
  • Housed in Class II GRP enclosure for lighter and compact design

RS4 Tier 3 is an integrated insulation monitoring and earth fault location system. Utilising proven Bender technology seen in previous variants (RS3), this Tier 3 compliant RS4 is designed to comply with Network Rail standard NR/L2/SIGELP/27725. This innovative, cutting edge technology is available as a new or retrofit solution, to deliver monitoring and protection for railway electrical systems on the UK’s rail infrastructure.

RS4 Tier 3 enables monitoring and fault location with improved accuracy and advanced sensitivity capabilities. The increased sensitivity strengthens fault location from the 20kΩ pre-warning level to 100kΩ.

The Network Rail certified Tier 3 system provides overall IR measurements, as well as feeder level fault location. Housed within a Class II GRP enclosure, Tier 3 is lighter and more compact in comparison to the previous RS3 version.

Simple to retrofit and update existing RS3 units, RS4 Tier 3 offers a cost-effective upgrade to legacy equipment that is compatible with existing Intelligent Infrastructure remote condition monitoring through data loggers.


  • Insulation Monitoring and Fault Location Systems used on Signal Power Systems
  • Identifies decline in insulation resistance (IR) values
  • 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 – pre-warning and alarm.
  • Standardised for use across Network Rail installations
  • Supplied in self-contained 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
  • Lockable front hinged door with viewing window


  • Rail signalling, relay rooms and trackside locations
  • For use with trackside power distribution systems up to 650V AC, Signal Power monitoring, Points System monitoring and Level Crossing Systems monitoring.

Downloads for RS4 Tier 3

Market Segment Brochures Bender Rail Signalling Protection Systems 10.8 MB EN2019/05/13 11:54:5713.05.2019 11:54:57

RS4 Tier 3 Variants

Bender Part NoNetwork Rail PADs no
RS4 Tier 30086/001406