CHAPTER 4: SETPOINTS
PROTECTION
845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
4–231
Figure 4-89: Underfrequency Protection logic diagram
LED
: PICKUP
Current Inputs
Phase
A
Current
(I
A
)
Phase B Current
(I
B
)
Phase C Current
(I
C)
SETPOINTS
BLOCK
:
Of
f=
0
AND
SETPOINTS
UNDERFREQ
1
FUNCTION
:
Disabled
T
rip
Alarm
Latched
Alarm
Configurable
OR
None
Positive
-
sequence
SETPOINTS
UNDERFREQ
1
MINIMUM CURRENT
:
I
=
MINIMUM
SETPOINTS
UNDERFREQ
1
MINIMUM VOL
T
AGE
:
AND
SETPOINTS
UNDERFREQ
1
PICKUP
:
0
<
f
=
PICKUP
FREQUENCY
f
RUN
SETPOINTS
UNDERFREQ
1
PICKUP
DELA
Y
:
t
PKP
t
DPO
UNDERFREQ
1
DROPOUT
DELA
Y
:
Underfreq
1
OP
FlexLogic Operands
Underfreq
1
PKP
AND
AND
AND
Command
RESET
OR
LED
: ALARM
LED
: TRIP
Operate Output Relay
1
(TRIP
)
WYE
DEL
T
A
VA
VA
B
VB
VBC
VC
VCA
Vx
RUN
V
=
MINIMUM
RUN
SETPOINTS
OUTPUT
RELA
Y
3 (X)
Do Not Operate
,
Operate
S
LA
TCH
Set
-
Dominant
R
SETPOINTS
UNDERFREQ
1
SIGNAL
INPUT
:
Positive
-
sequence
Composite
V
oltage Inputs
892737A3.cdr
Summary of Contents for 845
Page 10: ...VIII 845 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL ...
Page 219: ...CHAPTER 4 SETPOINTS SYSTEM 845 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL 4 91 ...
Page 221: ...CHAPTER 4 SETPOINTS SYSTEM 845 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL 4 93 ...
Page 222: ...4 94 845 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL SYSTEM CHAPTER 4 SETPOINTS ...
Page 223: ...CHAPTER 4 SETPOINTS SYSTEM 845 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL 4 95 ...
Page 224: ...4 96 845 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL SYSTEM CHAPTER 4 SETPOINTS ...
Page 225: ...CHAPTER 4 SETPOINTS SYSTEM 845 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL 4 97 ...
Page 226: ...4 98 845 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL SYSTEM CHAPTER 4 SETPOINTS ...
Page 227: ...CHAPTER 4 SETPOINTS SYSTEM 845 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL 4 99 ...
Page 396: ...4 268 845 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL MONITORING CHAPTER 4 SETPOINTS ...
Page 526: ...6 22 845 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL FLEXELEMENTS CHAPTER 6 METERING ...