ABB RELION REX640, Техническое руководство, Страница: 1398 / 1960

7.4 Cable fault detection RCFD (ANSI CFD)
7.4.1 Identification
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Cable fault detection RCFD CFD CFD
7.4.2 Function block
Figure 793: Function block
7.4.3 Functionality
The self-clearing fault detection function (RCFD) calculates half cycle DFT of the
current signal for all the three phases and earth and uses it to detect a self-clearing
fault pronounced primarily in cable networks.
The function provides individual counter values for number of times a self-clearing
fault is observed in each phase and earth. The function determines the self-clearing
fault is detected in all three phases or earth.
7.4.4 Analog input configuration
RCFD has two analog group inputs which must be properly configured.
Table 1332: Analog inputs
Input Description
I3P Three-phase currents.
IRES Measured residual current
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 troubleshooting, check the contents of this chapter and also the preprocessing
blocks in this document. The configuration can be written to the protection relay
once the mismatch is corrected.
Condition monitoring functions 1MRS759142 F
1398 REX640
Technical Manual