Sel 751A - Table 4.8 Phase A, B, and C Time-Overcurrent Settings

4.10
SEL-751A Relay Instruction Manual Date Code 20100129
Protection and Logic Functions
Basic Protection
Each element can be torque controlled using appropriate SELOGIC equations
(e.g., when 51P1TC := IN401 the 51P1 element will be operational only if
IN401 is asserted).
The phase time-overcurrent elements, 51AT, 51BT, and 51CT, respond to A,
B, and C phase currents, respectively, as shown Figure 4.3.
Table 4.8 Phase A, B, and C Time-Overcurrent Settings
Setting Prompt Setting Range
Setting Name :=
Factory De fault
TOC TRIP LVL OFF, 0.50–16.00 A
a
,
0.10–3.20 A
b
a
For I
NOM
= 5 A.
b
For I
NOM
= 1 A.
51AP := 6.00
51AP := 1.2
TOC CURVE SEL U1, U2, U3, U4, U5, C1,
C2, C3, C4, C5
51AC := U3
TOC TIME DIAL 0.50–15.00
c
,
0.05–1.00
d
c
For 51_C := U_ .
d
For 51_C := C_.
51ATD := 3.00
EM RESET DELAY Y, N 51ARS := N
CONST TIME ADDER 0.00–1.00 sec 51ACT := 0.00
MIN RESPONSE TIM 0.00–1.00 51AMR := 0.00
TOC TRQ CONTROL SELOGIC 51ATC := 1
TOC TRIP LVL OFF, 0.50–16.00 A
a
,
0.10–3.20 A
b
51BP := 6.00
51BP := 1.2
TOC CURVE SEL U1, U2, U3, U4, U5, C1,
C2, C3, C4, C5
51BC := U3
TOC TIME DIAL 0.50–15.00
c
,
0.05–1.00
d
51BTD := 3.00
EM RESET DELAY Y, N 51BRS := N
CONST TIME ADDER 0.00–1.00 sec 51BCT := 0.00
MIN RESPONSE TIM 0.00–1.00 51BMR := 0.00
TOC TRQ CONTROL SELOGIC 51BTC := 1
TOC TRIP LVL OFF, 0.50–16.00 A
a
,
0.10–3.20 A
b
51CP := 6.00
51CP := 1.2
TOC CURVE SEL U1, U2, U3, U4, U5, C1,
C2, C3, C4, C5
51CC := U3
TOC TIME DIAL51_C 0.50–15.00
c
,
0.05–1.00
d
51CTD := 3.00
EM RESET DELAY Y, N 51CRS := N
CONST TIME ADDER 0.00–1.00 sec 51CCT := 0.00
MIN RESPONSE TIM 0.00–1.00 51CMR := 0.00
TOC TRQ CONTROL SELOGIC 51CTC := 1