Circuit Protection Relay News

New EFR-4/EFR-5 Earth Leakage Protection Relay from FDB Electrical

efr51The EFR-4/EFR-5 Earth Leakage Protection Relay from FDB Electrical forms part of their extensive Optima range of low cost, high specification RCD’s and can be specified at a wide range of trip levels and response times for precise system protection.

The EFR-4/EFR-5 is designed for medium to high current applications where space is a limitation. It is housed in a compact Din-rail mounting enclosure complete with integral 28 or 46mm C.T. sensory coil and fitted with test, reset buttons and LED status indication.

This non-invasive sensing of 28mm (EFR-4) or 46mm (EFR-5) cable capacity is a significant factor in speedy installation for larger industrial and automated machines, e.g. electric motors, automated manufacturing assembly lines etc.

Fully encapsulated construction of the EFR-4 and 5 provides excellent temperature stability together with high immunity against shock and vibration. Housed in flame retardant ABS material as standard the EFR-4/EFR-5 Built-in features include fail-safe operation, manual reset after fault trip, auto reset after power failure and trip status latched until reset (with power supply on). A Non-Failsafe version is available to special order – this should be used in applications where shunt tripping of primary/supply breakers makes failsafe impractical.

The EFR-4/EFR-5 is designed to react to alternating current only and to reject stray DC signals. It maintains accuracy over an extremely wide frequency band from 5Hz to 800Hz thus making the unit suitable for application on variable frequency drives. The EFR-4/EFR-5 can be used on solid, medium or high resistance grounded installations and, by using the recommended artificial ground package, even on ungrounded installations.


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