HighTECH Line – MRR1
MULTIFUNCTIONAL GENERATOR ROTOR PROTECTION RELAY
The generator rotor protection relay MRR1 com-bines rotor earth fault protection, excitation over- and undercurrent protection as well as rotating diode failure protection.
Thus providing a powerful protection regarding the rotor of synchronous generators, covering the following ANSI codes:
37 DC undercurrent relay
40 Field relay
58 Rectification failure relay
64 Ground detector relay
76 DC over current relay
The MRR1 is recommended for synchronous generators and motors above 1 MVA rating.
The rotor earth fault element detects high- and low resistance earth faults of the rotor winding. It is equipped with two stages, one for alarm, one for trip.</P.
The excitation current protection element super-vises the DC excitation current of brushless excitor machines. The protective functions are: Undercurrent, over current and ripple detection for diode failure protection.
- Detection of high impedance earth faults with a test frequency of 0.5 Hz
- Short circuit and overvoltage proof measuring input for the earth fault protection
- Excitor current measurement galvanically isolated via Hall-transducer, measuring range 0 to 20 A
- Display of insulation resistance
- Display of the excitation current
- Excitation current over- and undercurrent protection with independent settings for current and delay time
- Detection of diode failures by supervision of the ripple component of the excitation current
- Two stage supervision of the rotor insulation resistance with independent settings for resistance and time delay
- Two trip relays, one for excitation under- and over current, one for diode failure detection
- Digital inputs for blocking and for remote reset
- Programmable function of the blocking input
- Programmable assignment of protective functions to output relays
- Remote interfacing via RS485
