Problem
Solution
The measured current
amplitudes are OK but
the angles are strange./
The phase unbalance
protection trips
immediately after
activation./
The earth fault
protection trips
immediately after
activation.
The phase currents are connected to the measurement module but the order or polarity of one or all
phases is incorrect. In relay settings, go to
Measurement
→
Phasors and check the "Phase current
vectors" diagram. When all connections are correct, the diagram (symmetric feeding) should look
like this:
See the following tables for the most common problems with phase polarity and network rotation
(mixed phases).
The following image presents the most common problems with phase polarity. Problems with phase
polarity are easy to find because the vector diagram points towards the opposite polarity when a phase
has been incorrectly connected.
A
AQ
Q-S215
-S215
Instruction manual
Version: 2.04
54
Summary of Contents for AQ-S215
Page 1: ...AQ S215 Bay control IED Instruction manual...
Page 249: ...Figure 7 4 151 Example block scheme A AQ Q S215 S215 Instruction manual Version 2 04 248...
Page 269: ...Figure 8 13 172 Device installation A AQ Q S215 S215 Instruction manual Version 2 04 268...
Page 287: ...10 Ordering information A AQ Q S215 S215 Instruction manual Version 2 04 286...