GE Industrial Solutions Entellisys 4.0 System User Manual - Manual (Page 249)

Alarms and events description and system troubleshooting guide 249
A
Voltage Below Underfreq Alarm
Blocking Voltage The voltages on all three phases have
dropped below the alarm only
underfrequency blocking voltage threshold.
Voltage Above Underfreq Alarm
Blocking Voltage The voltage on at least one of the three
phases has exceeded the alarm only
underfrequency blocking voltage threshold.
Pickup Underfrequency Underfrequency relay has entered pickup
Breaker Trip Underfrequency Underfrequency relay has operated
Dropout Underfrequency Underfrequency relay has dropped out of
pickup
Voltage Below Underfrequency
Blocking Voltage The voltages on all three phases have
dropped below the underfrequency blocking
voltage threshold.
Voltage Above Underfrequency
Blocking Voltage The voltage on at least one of the three
phases has exceeded the underfrequency
blocking voltage threshold.
Alarm Pickup Overfrequency Alarm only overfrequency relay has entered
pickup
Alarm Overfrequency Alarm only overfrequency relay has operated
Alarm Dropout Overfrequency Alarm only overfrequency relay has dropped
out of pickup
Voltage Below Overfreq Alarm
Blocking Voltage The voltages on all three phases have
dropped below the alarm only overfrequency
blocking voltage threshold.
Voltage Above Overfreq Alarm
Blocking Voltage The voltage on at least one of the three
phases has exceeded the alarm only
overfrequency blocking voltage threshold.
Pickup Overfrequency Overfrequency relay has entered pickup
Breaker Trip Overfrequency Overfrequency relay has operated
Dropout Overfrequency Overfrequency relay has dropped out of
pickup
Voltage Below Overfrequency
Blocking Voltage The voltages on all three phases have
dropped below the overfrequency blocking
voltage threshold.
Voltage Above Overfrequency
Blocking Voltage The voltage on at least one of the three
phases has exceeded the overfrequency
blocking voltage threshold.
Relays - Bus Differential
Table A-2 Sequence of events description and troubleshooting guide
Event Description Notes and Troubleshooting tips