Voltage-Unbalance Relay Delay; Current-Unbalance Relay Pickup; Current-Unbalance Relay Delay; Undervoltage Relay Pickup - GE MicroVersaTrip Plus Series User Manual

2.
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Figure 26. Trip Unit display for voltage-unbalance relay pickup.

Voltage-Unbalance Relay Delay

This function sets the delay time before a voltage­
unbalance trip occurs. The range of delays is 1 to 1 5
seconds, in steps of 1 second. Choosing
voltage-unbalance protection. The Trip Unit display
is shown in Figure 27.
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f.Lf
Figure 27. Trip Unit display for voltage-unbalance relay delay.

Current-Unbalance Relay Pickup

This function compares the true RMS current in the
highest or lowest phase with the average of all three
phases and initiates a trip if the difference exceeds
the set point. The range of set points is 1 0 to 50% of
the unbalance, with an increment of 1 % . The Trip
Unit display is shown in Figure 28.
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f Lf
Figure 28. Trip Unit display for current-unbalance relay pickup.

Current-Unbalance Relay Delay

This function sets the delay time before a current­
unbalance trip occurs. The range of delays is 1 to 1 5
seconds, in steps of 1 second. Choosing
SETUP
PI C KUP
disables
O F F
SETUP
s
DELAY
SETUP
PI C KUP
disables
O F F
current-unbalance protection. The Trip Unit display
is shown in Figure 29.
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f.Lf
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Figure 29. Trip Unit display for current-unbalance relay delay.

Undervoltage Relay Pickup

This function measures the true rms voltage in all
phases and initiates a trip if any phase voltage drops
below the set point. The range of set points is 50 to
90% of the nominal voltage, with an increment of
1 % . The Trip Unit display is shown in Figure 30.
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Figure 30. Trip Unit display for undervoltage relay pickup.

Undervoltage Relay Zero-Volt Trip Enable

This function determines if the relay trips when all
three phase voltages drop to zero volts. The Trip
Unit display for zero-volt trip disabled is shown in
Figure 3 1 . The Trip Unit display for zero-volt trip
enabled is shown in Figure 32.
., VOLTS
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Figure 3 1 . Trip Unit display for undervoltage relay zero-volt trip
20
SETUP
s
DELAY
SETUP
PICKUP
SETUP
disabled.