Sel SEL-421 - Page 152

R.1.110
SEL-421 Relay Reference Manual Date Code 20111215
Protection Functions
Trip Logic
TPA Trip A-phase
TPB Trip B-phase
TPC Trip C-phase
TRIP Trip A-phase or B-phase or C-phase
3PT Three-pole trip
SPT Single-pole trip
TPA1 Circuit Breaker 1 trip A-phase
TPB1 Circuit Breaker 1 trip B-phase
TPC1 Circuit Breaker 1 trip C-phase
TPA2 Circuit Breaker 2 trip A-phase
TPB2 Circuit Breaker 2 trip B-phase
TPC2 Circuit Breaker 2 trip C-phase
TOP Trip during open pole timer is asserted
ULMTR1 Circuit Breaker 1 unlatch manual trip
ULMTR2 Circuit Breaker 2 unlatch manual trip
Table 1.73 Trip Logic Relay Word Bits (Sheet 2 of 2)
Name Description