CHAPTER 6: SETPOINTS
S3 PROTECTION
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
6–105
Figure 6-46: Broken conductor logic diagram
SE
TP
OINT
=
Disabled
=
Alarm
FUNCTION
=
Lat
ched Alarm
=
Contr
ol
=T
rip
LED
:A
LARM
OR
Volatile
,
Reset
-dominant
Lat
ch
S
R
AND
AND
RESE
T
Command
AND
LED
:TRIP
Operat
e Output
Relay
1
(TRIP)
Trip (to Br
eaker Failur
e)
OR
SE
TP
OINTS
=O
n
BL
OCK
1:
=O
n
BL
OCK
2:
=O
n
BL
OCK
3:
OR
AND
SE
TP
OINTS
RUN
I-1
MAX
:
|I_1
/I
_2
| >
I_
2/
I_
1
RA
TIO
AND
SE
TP
OINT
PICKUP DEL
AY
:
0
T
PKP
SE
TP
OINTS
OUTPUT REL
AY
X
Do Not Operat
e, Operat
e
LED
:PICKUP
Message
Event Recor
der
Transient Recor
der
Message
Event Recor
der
Transient Recor
der
I_
1
MIN:
I_
2/
I_
1
RA
TI
O
:
|I_1
| >
I_
1
MIN
|I_1
| <
I_
1
MAX
SE
TP
OINTS
RUN
|IA
| <
I_
1
MIN
I_
1
MIN
|IB
| <
I_
1
MIN
|IC
| <
I_
1
MIN
|IA
’|
-
|IA
| >
0.
05
x CT
|IB’
|-
|IB
| >
0.
05
x CT
|IC’
|-
|IC
| >
0.
05
x CT
Phase A curr
ent
(IA
)
Curr
ent Inputs
Phase B curr
ent
(IB
)
Phase C curr
ent
(IC
)
Pos Seq curr
ent
(I_1
)
Calculat
ed by r
elay
Neg Seq curr
ent
(I_2
)
I’ is
4
cycles old
AND
AND
AND
OR
0
2
cyc
OR
898854A1.cdr