The protective stator earth fault relay type RMC-142D forms part of a complete DEIF series of relays for protection and control of generators. The RMC-142D is primarily designed for land-based installations. The RMC-142D is CE-marked and is applied for protection of voltage sources and load networks against earth fault in a solid earthing or a low-resistance earthing system.
The relay measures the leakage or a short circuit from one or more of the phases to earth.
In order to obtain a short response time on a fault condition, the measurement is based on peak values. The earth fault current protection is for example obtained by connecting an external current transformer in the star point of the protected voltage source.
In order to prevent malfunction due to 3rd harmonic, the RMC-142D is equipped with a special filter cutting off frequencies higher than 50/60 Hz. The set point values are set on the front of the relay by means of potentiometers. If exceeded, a fault signal is generated, and the associated yellow LED is lit.
Relay output :
The RMC-131D is provided with one relay coil with two maximum contacts. The relay can be configured either to normally energised or normally de-energised. The contacts may be set to open or to close on activation (same function on both contacts).
Normally energised contact :
Recommended for marine installations for warning and alarm purposes. In case of an auxiliary supply dropout, the contact is immediately activated.
Normally de-energised contact :
Recommended for marine installations for regulating and control purposes. An auxiliary supply failure will not result in an unwanted activation of the contact.
●Earth fault protection at 2 levels
●Built-in filter for 3rd harmonic
●LED indication of fault condition
●LED indication for activated relay
Borna Niroo Karan (Bornika) is the exclusive agent of DEIF in the fields of consultation , sales and distribution of power industry products including Stator earth fault relay products .