Appendices
51
7.1.2. Alarm Conditions
Voltage phase imbalance exceeds the set
threshold
Current phase imbalance exceeds the set
threshold
Voltage greater than the upper threshold
Voltage greater than the upper threshold
Voltage greater than the upper threshold
Voltage less than acceptable (No voltage) limit
Voltage less than acceptable (No voltage) limit
Voltage less than acceptable (No voltage) limit
Current exceeds upper threshold limit
Current exceeds upper threshold limit
Current exceeds upper threshold limit
All currents were measured below their
acceptable (No current) limits
One or more currents were measured below their
acceptable limits
One or two voltage phases were compatible with
zero (below No voltage limit)
All the voltage phases were compatible with zero
(below No voltage limit)
The power lines were not sufficiently stable to
allow the algorithm to obtain data (amplitude and
frequency variations of current and voltage were
excessive)
General fault consisting of one or more of:
No data obtained, no zero crossings detected,
perfect phase balance (voltage or current)
The phase ordering used by AMU is incorrect and
must be rectified.
Voltage phase angles incompatible with 120º