ABB REG670 - Function Block

current is default (i.e. recommended) measurement for generators with static
excitation system. When the DC current is used, the function can provide a DC current
ripple alarm, due to possible problem with the static excitation equipment. The rotor
DC current can be also sent to the plant supervisory system via communication
channel or displayed on the IED built-in HMI.
The function can also detect undercurrent condition in the rotor winding which
indicates either under-excitation or loss of excitation condition of the generator.
The function is designed to work on 50/60 Hz systems.
8.16.3 Function block
IEC12000028-1-en.vsd
GRPTTR
I3P*
BLOCK
BLOCKUC
SETLKOUT
RESET
TRIP
TRIPUC
START
STARTUC
LOCKOUT
BLKRECL
ALRIPPLE
IMEAS
IEC12000028 V1 EN
Figure 218: GRPTTR function block
8.16.4 Signals
Table 256: GRPTTR Input signals
Name
Type Default Description
I3P GROUP
SIGNAL
- Current Group Connection
BLOCK BOOLEAN 0 Block of function
BLOCKUC BOOLEAN 0 Block under-current protection feature
SETLKOUT BOOLEAN 0 Input for forcing the output LOCKOUT
RSTLKOUT BOOLEAN 0 Reset of the output LOCKOUT and theta to 0%
Table 257: GRPTTR Output signals
Name
Type Description
TRIP BOOLEAN General trip signal from the function
TRIPUC BOOLEAN Trip signal from under-current feature
START BOOLEAN General start signal from the function
STARTUC BOOLEAN Start signal from under-current feature
LOCKOUT BOOLEAN Trip lockout output (latched)
Table continues on next page
Section 8 1MRK502052-UEN B
Current protection
464
Technical manual