GE Feeder Management Relay 750 User Manual

8-26 750/760 Feeder Management Relay GE Multilin
8.4 PROTECTION SCHEMES 8 COMMISSIONING TESTS
8
9. Repeat Steps 1 through 7, substituting V
bn
for V
an
, V
cn
for V
bn
and V
an
for V
cn
.
The following procedure checks Pickup with Three Phases For Operation:
1. Inject V
an
= V
bn
= V
cn
= a voltage between the MIN OPERATING VOLTAGE and the pickup voltage into the bus voltage
input of the relay. The Pickup LED should be on.
2. Slowly raise V
an
until the Pickup LED goes out. This reset voltage should be the pickup value plus 2% of VT.
3. Reduce V
an
until the Pickup LED comes on. This is the pickup voltage of V
an
.
4. Slowly raise V
bn
until the Pickup LED goes out. This reset voltage should be the pickup value plus 2% of VT.
5. Reduce V
bn
until the Pickup LED comes on. This is the pickup voltage of V
bn
6. Slowly raise V
cn
until the Pickup LED goes out. This reset voltage should be the pickup value plus 2% of VT.
7. Reduce V
cn
until the Pickup LED comes on. This is the pickup voltage of V
cn
.
8. Lower V
an
until the Pickup LED goes out. This is the MIN OPERATING VOLTAGE of V
an
minus 2% of VT.
9. Slowly raise V
an
until the Pickup LED comes on. This is the MIN OPERATING VOLTAGE level.
10. Reduce V
bn
until the Pickup LED goes out. This is the MIN OPERATING VOLTAGE of V
bn
minus 2% of VT.
11. Slowly raise V
bn
until the Pickup LED comes on. This is the MIN OPERATING VOLTAGE level.
12. Reduce V
cn
until the Pickup LED goes out. This is the MIN OPERATING VOLTAGE of V
cn
minus 2% of VT.
13. Slowly raise V
cn
until the Pickup LED comes on. This is the MIN OPERATING VOLTAGE level.
b) BUS UNDERVOLTAGE (DELTA VTS ONLY)
To test Bus Undervoltage for Delta VTs, use the test connections specified in Figure 8–2: Relay Test Wiring – Delta Con-
nection on page 8–3.
The following procedure tests Pickup with One Phase For Operation:
1. Inject V
ab
= V
cb
= nominal voltage into the bus voltage input of the relay. The Pickup LED should be off.
2. Slowly lower V
ab
until the Pickup LED comes on. This is the pickup voltage.
3. Continue to lower V
ab
until the Pickup LED goes out. This is the MIN OPERATING VOLTAGE minus 2% of VT.
4. Raise V
ab
until the Pickup LED comes on, and continue to increase until the indicator goes out. This is the reset volt-
age, which should be the pickup value plus 2% of VT.
5. Repeat Steps 1 through 4 except adjust V
bc
.
The following procedure tests Pickup with Two or Three Phases For Operation:
1. Inject V
ab
= nominal voltage and V
cb
= a voltage between the MIN OPERATING VOLTAGE and the pickup voltage into the
bus voltage input of the relay. The Pickup LED should be on.
2. Slowly raise V
cb
until the Pickup LED goes out. This reset voltage should be the pickup value plus 2% of VT.
3. Reduce V
cb
until the Pickup LED comes on. This is the pickup voltage of V
cb
.
4. Continue to lower V
cb
until the Pickup LED goes out. This is the MIN OPERATING VOLTAGE of Vcb minus 2% of VT.
5. Slowly raise V
cb
until the Pickup LED comes on. This is the MIN OPERATING VOLTAGE level.
6. Reduce V
ab
until the Pickup LED goes out. This is the MIN OPERATING VOLTAGE of V
ab
minus 2% of VT.
7. Slowly raise V
ab
until the Pickup LED first comes on and then goes out. This is the reset voltage, which should be the
pickup value plus 2% of VT.
8. Lower V
ab
until the Pickup LED comes on. This is the pickup voltage of V
ab
.
c) BUS UNDERVOLTAGE (WYE AND DELTA VTS)
To test Bus Undervoltage for Wye and Delta VTs, use the test connections specified in Figure 8–1: Relay Test Wiring – Wye
Connection or Figure 8–2: Relay Test Wiring – Delta Connection on page 8–3.
The procedures for testing Indications and Operations are the same as those outlined for Phase TOC 1 on page 8–16.
The following procedure tests Blocking From Logic Inputs:
Courtesy of NationalSwitchgear.com

GE Feeder Management Relay 750 Specifications

General

Brand	GE
Model	Feeder Management Relay 750
Category	Protection Device
Language	English