Fail-safe Relays

For over 20 years, Intertech Rail has specialized in the design and manufacturing of Fail-Safe Rail Relays, essential components widely applied in railway signaling and control systems.


With more than 300 variations available, all relays are engineered under the fail-safe principle: in the event of any malfunction or breakdown, the relay automatically returns to its safest position through gravity and mechanical design. This guarantees maximum reliability and compliance with the highest railway safety standards.


Fail-Safe Relays remain the preferred solution in the railway industry due to their proven durability, operational stability, and ability to secure safe performance in critical applications.


Intertech Rail manufactures the full spectrum of relay types on demand, with the B1 and B2 models being the most commonly used and detailed in our catalogs. We also supply legacy and discontinued relay models. Simply provide the required Relay Part Number to receive a tailored quotation.

Frequently Asked Questions

  • What is an Overload relay?

    The overload relay is designed to protect motors from excessive current. In rail applications, overload relays are commonly used in the power supply systems of trains. If the motor draws too much current, the overload relay will trip, preventing damage to the motor and ensuring the safety of the system.

  • That is a Fail-safe Thermal relay


    Thermal relays are used to protect motors from overheating. They work by measuring the temperature of the motor and tripping if it exceeds a preset value. In rail applications, thermal relays are commonly used in the traction systems of trains. If the motor overheats, the thermal relay will trip, preventing damage to the motor and ensuring the safety of the system.

  • What is a fail-safe Earth fault relay?

    Earth fault relays are used to detect faults in the insulation of the system. In rail applications, earth fault relays are commonly used in the track circuits. If a fault occurs in the insulation of the track circuit, the earth fault relay will trip, isolating the section of track and preventing damage to the system.

  • What is a fail-safe Short circuit relay?

    Short circuit relays are used to protect the system from short circuits. In rail applications, short circuit relays are commonly used in the traction systems of trains. If a short circuit occurs, the short circuit relay will trip, isolating the faulty section of the system and preventing damage to the system.

  • What is a Time delay relay?

    Time delay relays are used to provide a time delay before tripping. In rail applications, time delay relays are commonly used in the power supply systems of trains. If a fault occurs in the system, the time delay relay will provide a delay before tripping, allowing the system to recover from a momentary fault and preventing unnecessary trips.