GE 339

CHAPTER 6: SETPOINTS S3 PROTECTION
339 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL 6–55
Figure 6-23: Undercurrent logic diagram
896808A1.CDR
S3 UNDERCURRENT
MOTOR STATUS Stopped
AND
IA_mag < PICKUP
S3 UNDERCURRENT
U/CURR TRIP PKP
RUN
IB_mag < PICKUP
IC_mag < PICKUP
IA_mag < PICKUP
S3 UNDERCURRENT
U/CURR ALARM PKP
RUN
IB_mag < PICKUP
IC_mag < PICKUP
OR
OR
S3 UNDERCURRENT
U/CURR ALARM DELAY
t
PKP
0
LOGIC OPERAND U/CURR TRIP OP ANY TRIP OP
S3 UNDERCURRENT
U/CURR TRIP DLY
t
PKP
0
LOGIC OPERAND U/CURR ALARM OP ANY ALARM OP
S R
LATCH
AND
AND
S3 UNDERCURRENT
U/CURR TRIP FUNC
DISABLED = 0
S3 UNDERCURRENT
BLK U/C ON START
t
BLK
0
BLOCK 1 BLOCK 2 BLOCK 3
OFF = 0 OFF = 0 OFF = 0
OR
S3 UNDERCURRENT U/CURR ALARM FUNC ENABLED = 1
IA
ACTUAL VALUE
IB
IC
Running
S2 MOTOR ENABLE 2-SPD MOTOR DISABLED = 0 MOTOR SPEED INDICATION LOW SPEED
OR
AND
U/CURR TRIP PKP
U/CURR ALARM PKP
SETTINGS SETTINGS
SETTINGS
SETTING
SETTINGS
SETTINGS
SETTING
SETTINGS
SETTINGS
TARGET MESSAGE Undercurrent Alarm State: Operate Undercurrent Alarm State: Pickup TARGET MESSAGE Undercurrent Trip State: Operate Undercurrent Trip State: Pickup
OR
AND
AND
INPUTS
Emergency Restart Input Lockout Reset Input
SETTINGS
Off = 0 Lockout Reset Off = 0
Emergency Restart
S4 CONTROLS
ANY ALARM PKP
ANY TRIP PKP
KEYPAD RESET
AND
Reset Input
Reset Off = 0
DISABLED = 0
SETTING
OUTPUT RELAY X
Do Not Operate, Operate