GE Feeder Management Relay 750 User Manual

GE Multilin 750/760 Feeder Management Relay 8-27
8 COMMISSIONING TESTS 8.4 PROTECTION SCHEMES
8
1. Inject voltage into the required number of phases to cause a pickup.
2. Assert a logic input to provide a "Block Undervolt 1 (2)". The Pickup LED should immediately go out.
3. Repeat Steps 1 and 2 for logic input “Block 1 Trip Relay” as required.
The following procedure tests the Bus Undervoltage element timing:
1. Connect the “Stop Trigger."
2. Set the voltage source to nominal voltage.
3. Reset the timer. Turn the voltage off in the required number of phases, and measure the operating time.
4. Repeat Steps 2 and 3 four more times and obtain an average of the time intervals.
5. Reset the relay and disconnect the “Stop Trigger.”
d) LINE UNDERVOLTAGE
The following procedure tests the Line Undervoltage pickup:
1. Inject nominal voltage into the line voltage input of the relay. The Pickup LED should be off.
2. Slowly lower the voltage until the Pickup LED comes on. This is the pickup voltage.
3. Continue to lower the voltage until the Pickup LED goes out. This is the
MIN OPERATING VOLTAGE minus 2% of VT.
4. Raise the voltage until the Pickup LED comes on, and continue to increase until the indicator goes out. This is the reset
voltage, which should be the pickup value plus 2% of VT.
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 the Blocking From Logic Inputs:
1. Inject voltage to cause a pickup.
2. Assert a logic input to provide a "Block Undervolt 3 (4)". The Pickup LED should immediately go out.
3. Repeat Steps 1 and 2 for logic input “Block 1 Trip Relay” as required.
The following procedure tests the Line Undervoltage element Timing:
1. Connect the “Stop Trigger".
2. Set the voltage source to nominal voltage.
3. Reset the timer. Turn on the voltage, and measure the operating time.
4. Repeat Steps 2 and 3 four more times and obtain an average of the time intervals.
5. Reset the relay and disconnect the “Stop Trigger".
e) OVERVOLTAGE (WYE VTS ONLY)
To test Overvoltage for Wye VTs, use the test connections specified in Figure 8–1: Relay Test Wiring – Wye Connection on
page 8–3. The following procedure tests Pickup with One Phase For Operation:
1. Inject V
an
= V
bn
= V
cn
= 0 into the bus voltage input of the relay. The Pickup LED should be off.
2. Slowly raise Van until the Pickup LED comes on. This is the pickup voltage.
3. Lower V
an
until the Pickup LED goes out. This is the reset voltage, which should be the pickup value minus 2% of VT.
4. Repeat Steps 1 through 3 except adjust V
bn
and V
cn
in turn.
The following procedure tests Pickup with Two Phases For Operation:
1. Inject V
an
= V
bn
= nominal voltage and V
cn
= a voltage above the pickup into the bus voltage input of the relay. The
Pickup LED should be off.
2. Slowly raise V
an
until the Pickup LED goes on. This is the pickup voltage of V
an
.
3. Reduce V
an
until the Pickup LED goes off. This reset voltage of V
an
should be the pickup value minus 2% of VT.
4. Raise V
an
until the Pickup LED comes on.
5. Repeat Steps 1 through 4, substituting V
cn
for V
an
, V
an
for V
bn
and V
bn
for V
cn
.
Courtesy of NationalSwitchgear.com

GE Feeder Management Relay 750 Specifications

General

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