Schneider Electric 4000

Chapter 6—Alarms 63230-300-212

Setpoint-Controlled Relay Function s April 2001

Unbalance Voltage:

Pickupand dropout setpoints are entered in tenthsof percent, based on the

percentagedifference between each phase voltage withrespect to the aver-

ageof all phase voltages. For example,enter an unbalance of 7% as 70. The

unbalancevoltage alarm occurs when the phase voltage deviates from the

averageof the phase voltages, by the percentage pickupsetpoint, for the

specifiedpickup delay. The alarm clears when thepercentage difference

betweenthe phase voltage and the averageof all phases remains below the

dropout setpointfor the specified dropout delay (in seconds).

Phase Loss—Current:

Pickupand dropout setpointsare entered in amperes. The phase loss current

alarm occurs when anycurrent value (but not all current values) is equalt o

orbelow the pickup setpoint for the specified pickup delay(in seconds). The

alarm clears when one of the followingis true:

•All of the phases remainabove the dropout setpoint for the specified

dropout delay,or

•All of the phases dropbelow the phase loss pickup setpoint.

If all of the phasecurrents are equal to or below the pickup setpoint, during

thepickup delay,the phase loss alarm will not activate. This is consideredan

undercurrent condition. It shouldbe handled by configuring the under current

protectivefunctions.

Phase Loss—Volta ge:

Pickupand dropout setpoints are entered in volts. The phase loss voltage

alarm occurs when anyvoltage value (but not all voltage values)is equal to

orbelow the pickup setpoint for the specified pickup delay(in seconds). The

alarm clears when one of the followingis true:

•All of the phases remainabove the dropout setpoint for the specified

dropout delay(in seconds), OR

•All of the phases dropbelow the phase loss pickup setpoint.

If all of the phasevoltages are equal to or below the pickup setpoint, during

thepickup delay,the phase loss alarm will not activate. This is consideredan

under voltagecondition. It should be handled by configuring the under

voltageprotective functions.

Reverse Power:

Pickupand dropout setpoints are entered inkilowatts or kVARs.The reverse

poweralarm occurs when thepower flows in a negative direction and

remains ator below the negative pickup valuefor the specified pickup delay

(in seconds).The alarm clears when the power reading remains above the

dropout setpointfor the specified dropout delay (in seconds).

Phase Reversal:

Pickupand dropout setpoints and delays do not applyto phase reversal. The

phasereversal alarm occurs when the phasevoltage rotation differs fromt he

defaultphase rotation. The circuit monitor assumes that an ABC phase

rotationis norm al.If a CBA phase rotation is normal, the user must change

the circuit monitor’s phase rotation from ABC (default)to CBA. To change the

phase rotationfrom the display,from the main menu select Setup > Meter >

Advanced.For more informationabout changing the phase rotationsetting of

the circuit monitor, refer to “Advanced Meter Setup”on page 34.