GE 750 Instruction Manual page 369

CHAPTER 7: COMMISSIONING
750 FEEDER MANAGEMENT RELAY – INSTRUCTION MANUAL
 Raise V
the indicator goes out.
This is the reset voltage, which should be the pickup value plus 2% of
VT.
 Repeat last 4 steps except adjust V
The following procedure tests Pickup with Two or Three Phases For Operation:
 Inject V
OPERATING VOLTAGE
of the relay.
The Pickup LED should be on.
 Slowly raise V
This reset voltage should be the pickup value plus 2% of VT.
 Reduce V
This is the pickup voltage of V
 Continue to lower V
This is the
 Slowly raise V
This is the
 Reduce V
This is the
 Slowly raise V
This is the reset voltage, which should be the pickup value plus 2% of
VT.
 Lower V
This is the pickup voltage of V
Bus Undervoltage (Wye and Delta VTs)
To test Bus Undervoltage for Wye and Delta VTs, use the test connections specified in
FIGURE 7–1: Relay Test Wiring – Wye Connection or FIGURE 7–2: Relay Test Wiring – Delta
Connection on page 7–5.
The procedures for testing Indications and Operations are the same as those outlined for
Phase TOC 1 on page 7–25.
The following procedure tests Blocking From Logic Inputs:
 Inject voltage into the required number of phases to cause a pickup.
 Assert a logic input to provide a "Block Undervolt 1(2)".
The Pickup LED should immediately go out.
 Repeat last 2 steps for logic input "Block 1 Trip Relay" as required.
The following procedure tests the Bus Undervoltage element timing:
 Connect the "Stop Trigger."
 Set the voltage source to nominal voltage.
 Reset the timer.
until the Pickup LED comes on, and continue to increase until
ab
bc
= nominal voltage and V
ab cb
and the pickup voltage into the bus voltage input
until the Pickup LED goes out.
cb
until the Pickup LED comes on.
cb
.
cb
until the Pickup LED goes out.
cb
MIN OPERATING VOLTAGE
until the Pickup LED comes on.
cb
MIN OPERATING VOLTAGE
until the Pickup LED goes out.
ab
MIN OPERATING VOLTAGE
until the Pickup LED first comes on and then goes out.
ab
until the Pickup LED comes on.
ab
.
ab
PROTECTION SCHEMES
.
= a voltage between the
MIN
of V minus 2% of VT.
cb
level.
of V minus 2% of VT.
ab
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