Rotor Earth-Fault Protection, Injection Method Mrefptoc; Identification; Function Block; Functionality - ABB RELION REX640 Technical Manual

1MRS759142 C
4.2.5
4.2.5.1
4.2.5.2
4.2.5.3
4.2.5.4
REX640
Technical Manual

Rotor earth-fault protection, injection method MREFPTOC

Identification

Function description
Rotor earth-fault protection, injection
method

Function block

GUID-DE49B8E2-B844-40FA-A86C-D777CA1AEE3E V1 EN
Figure 263: Function block

Functionality

The rotor earth-fault protection, injection method, function MREFPTOC is used to
detect an earth fault in the rotor circuit of synchronous machines. MREFPTOC is used
with the injection device REK510, which requires a secured 58, 100 or 230 V AC
50/60 Hz input source and injects a 100 V AC voltage via its coupling capacitors to the
rotor circuit towards earth.
MREFPTOC consists of independent alarm and operating stages. The operating time
characteristic is according to definite time (DT) for both stages.
MREFPTOC contains a blocking functionality. It is possible to block function
outputs, timers or the function itself.

Analog channel configuration

MREFPTOC has one analog group input which must be properly configured.
Table 521: Analog signals
Input
IRES
See the preprocessing function blocks in this document for the
possible signal sources.
Improper analog channel configuration causes a validation error if the analog
channels are not completely configured or they do not match with certain settings. For
Protection functions
IEC 61850 IEC 60617
identification identification
MREFPTOC Io>R
Description
Residual current (measured or calculated)
Section 4
ANSI/IEEE C37.2
device number
64R
481