SKU: MVAJ105RA0802A

ALSTOM MVAJ105RA0802A MVAJ High-Speed Tripping Relay

The ALSTOM MVAJ105RA0802A is a high-speed, 10-contact tripping relay designed for substation protection. Featuring a 110/125VDC rating, high-burden circuitry for noise immunity, and a manual/electrical reset mechanism, this MVAJ module ensures rapid circuit breaker operation and reliable fault isolation in power distribution systems.

High-Speed Tripping and Circuit Isolation

The ALSTOM MVAJ105RA0802A functions as a high-speed, multi-contact tripping relay within the MVAJ product family, specifically designed for protection and control schemes in electrical substations. This module operates by receiving a signal from a primary protection relay and rapidly energizing its multiple output contacts to trip circuit breakers or isolate faulty plant sections. Because the MVAJ105 utilizes a robust “attracted armature” design, it achieves exceptionally fast operating times, which is critical for minimizing equipment damage during short-circuit events. Furthermore, this specific RA0802A variant ensures reliable galvanic isolation between the low-voltage control circuits and the high-voltage switching equipment.

Advanced Reset Logic and Contact Configuration

Beyond its basic tripping function, the MVAJ105RA0802A features specialized reset logic tailored for automated power systems. In addition to the primary operating coil, the module includes a hand-reset or electrical-reset mechanism, ensuring that the relay remains in the “tripped” state until an operator or a supervisory system acknowledges the fault. Because this unit is configured with a high number of output contacts, it can simultaneously signal an alarm, initiate a fault recorder, and trigger multiple breaker trip coils from a single input signal. Moreover, the relay’s high-burden design prevents accidental operation caused by induced voltages or capacitive discharge in long control cables. Consequently, the MVAJ105 is a cornerstone for complex busbar and transformer protection schemes.

Industrial Durability and Visual Diagnostics

ALSTOM (now GE Renewable Energy / Grid Solutions) has engineered the MVAJ105RA0802A to withstand the harsh electromagnetic environments found in utility-scale power stations. The module is housed in a standard “draw-out” case, which allows for rapid testing and replacement without disturbing the terminal wiring. Furthermore, the unit features a highly visible mechanical flag (target) indicator that provides maintenance personnel with an immediate visual confirmation that the relay has operated. Because the internal components are designed for high thermal stability, the relay maintains its timing accuracy across a wide range of ambient temperatures. Therefore, this combination of mechanical robustness and diagnostic transparency ensures long-term operational reliability in mission-critical infrastructure.