The protective reverse power relay type RMP-112D forms part of a complete DEIF series of relays for protection and control of generators and is applicable to both marine and land-based installations. Also available are reverse power relays (RMP-121D) . The RMP-112D is type-approved by major classification societies and is applied for protection of the prime mover against overload. This is especially required if the prime mover is undersized in proportion to the AC generator. Supervision of the reverse power will prevent a generator running in parallel with other generators from running as a motor - thus protecting the prime mover - and will at the same time ensure that the remaining generators connected to the system are not disconnected due to overload of these.
The relay measures all 3-phase currents and phase voltages. The TDM (Time-Division-Multiplication) principle ensures an accurate measurement of the RMS value of the power, irrespective of wave form and asymmetry.
The RMP-112D is available with the following couplings:
2W3 2-element 3-phase 3-wire, unbalanced load
3W3(4) 3-element 3-phase 3-wire (4-wire), unbalanced load
If either the power (P>) or the reverse power (-P>) exceeds its set point, the associated output is activated. The set point value is set on the front of the relay by means of a potentiometer. If exceeded, a fault signal is generated, and the associated yellow LED is lit.
Relay outputs :
The RMP-112D is provided with an output with a maximum contact, either normally energised or normally de-energised. The contact may be set to open or to close on activation.
Normally energised contact :
Recommended for land-based installations for warning and alarm purposes. In case of an auxiliary supply drop-out, 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.
●Combined overload/reverse power
●LED indication of alarm 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 reverse power relay products .