GE G30 Instruction Manual page 327

5 SETTINGS
• GEN UNBAL STG1 K-RESET: This setting defines the linear reset rate of the stage 1 element. It is the maximum reset
time from the threshold of tripping. This feature provides a thermal memory of previous unbalance conditions.
• GEN UNBAL STG2 PICKUP: This setting defines the pickup of the stage 2 element expressed as a percentage of the
nominal current as specified by
an alarm to prompt an operator to take some corrective action. The stage 2 element would typically be set at a safe
margin below the stage 1 pickup setting.
• GEN UNBAL STG2 PKP DELAY: This is the minimum operate time of the stage 2 element. This is set to prevent nui-
sance alarms during system faults.
1000
Tmax
100
10
1
0.1
0.01
Figure 5–74: GENERATOR UNBALANCE INVERSE TIME CURVES
GE Multilin
setting. The definite time element would normally be used to generate
GEN UNBAL INOM
K=1 K=4 K=15 K=40 K=100
0.1
Figure 5–75: GENERATOR UNBALANCE SCHEME LOGIC
G30 Generator Protection System
1 10
5.6 GROUPED ELEMENTS
Tmin
100
830714A1.CDR
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