GE 339

6–92 339 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
S3 PROTECTION CHAPTER 6: SETPOINTS
Figure 6-39: Underpower logic diagram
896822A1.CDR
S3 UNDERPOWER
MOTOR STATUS Stopped
AND
S3 UNDERPOWER
U/POWER TRIP PKP
RUN
S3 UNDERPOWER RUN
P = P + P + P
3ph a b c
S3 UNDERPOWER
U/POWER ALARM DELAY
t
PKP
0
LOGIC OPERAND U/POWER TRIP OP ANY TRIP OP
S3 UNDERPOWER
U/POWER TRIP DLY
t
PKP
0
LOGIC OPERAND U/POWER ALARM OP ANY ALARM OP
S R
LATCH
AND
AND
S3 UNDERPOWER
U/POWER TRIP FUNC
ENABLED = 1
S3 UNDERPOWER
BLK U/P ON START
t
BLK
0
BLOCK 1 BLOCK 2 BLOCK 3
OFF = 0 OFF = 0 OFF = 0
OR
S3 UNDERPOWER U/POWER ALARM FUNC ENABLED = 1
IA
ACTUAL VALUE
IB
IC
Running
U/POWER TRIP PKP
U/POWER ALARM PKP
SETTINGS
SETTINGS
SETTING
SETTINGS
SETTINGS
SETTING
SETTINGS
SETTINGS
TARGET MESSAGE Underpower Alarm State: Operate Underpower Alarm State: Pickup TARGET MESSAGE Underpower Trip State: Operate Underpower 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
P < Pickup
3ph
P = P + P + P
op a b c
P < Pickup
op
S2 VOLTAGE SENSING VT CONNECTION SETTINGS
Wye Delta
V
an
V
bn
V
cn
V
ab
V
bc
V
ca
U/POWER ALARM PICKUP
Fuse Failure LOGIC OPERAND DISABLED = 0
DISABLED = 0
SETTINGS
OUTPUT RELAY X Do Not Operate, Operate