Ground And Differential Accuracy Test - GE 469 Instruction Manual

7 TESTING
The 469 specification for differential current and 1 A/5 A ground current input accuracy is ±0.5% of 1 × CT for the 5 A input
and 0.5% of 5 × CT for the 1 A input. Perform the steps below to verify accuracy.
a) 5 A INPUT
1. Alter the following setpoints:
Õ
S2 SYSTEM SETUP
Õ
S2 SYSTEM SETUP
Õ
S2 SYSTEM SETUP
Õ
S2 SYSTEM SETUP
Measured values should be ±5 A. Inject the values shown in the table below into one phase only and verify accuracy of
2.
the measured values. View the measured values in:
A2 METERING DATA
INJECTED
CURRENT
5 A UNIT
0.5 A
1.0 A
2.5 A
5.0 A
b) 1 A INPUT
1. Alter the following setpoints:
Õ
S2 SYSTEM SETUP
Õ
S2 SYSTEM SETUP
Õ
S2 SYSTEM SETUP
Õ
S2 SYSTEM SETUP
Measured values should be ±25 A. Inject the values shown in the table below into one phase only and verify accuracy
2.
of the measured values. View the measured values in:
A2 METERING DATA
INJECTED
CURRENT
1 A UNIT
0.1 A
0.2 A
0.5 A
1.0 A
GE Multilin
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Õ×
CURRENT SENSING GROUND CT:
Õ×
CURRENT SENSING GROUND CT PRIMARY:
Õ×
CURRENT SENSING PHASE DIFFERENTIAL CT:
Õ×
CURRENT SENSING PHASE DIFFERENTIAL CT PRIMARY: 1
Õ
CURRENT METERING
EXPECTED MEASURED
CURRENT GROUND
READING CURRENT
100 A
200 A
500 A
1000 A
Õ×
CURRENT SENSING GROUND CT:
Õ×
CURRENT SENSING GROUND CT PRIMARY:
Õ×
CURRENT SENSING PHASE DIFFERENTIAL CT:
Õ×
CURRENT SENSING PHASE DIFFERENTIAL CT PRIMARY:
Õ
CURRENT METERING
EXPECTED MEASURED
CURRENT GROUND
READING CURRENT
100 A
200 A
500 A
1000 A
469 Motor Management Relay
7.2 HARDWARE FUNCTIONAL TESTING

7.2.3 GROUND AND DIFFERENTIAL ACCURACY TEST

5A Secondary
1000 A
5A Secondary
000 A
MEASURED DIFFERENTIAL CURRENT
PHASE A PHASE B
1A Secondary
1000 A
1A Secondary
1000 A
MEASURED DIFFERENTIAL CURRENT
PHASE A PHASE B
PHASE C
7
PHASE C
7-3