Supervision
Commissioning: Voltage Transformer Failure [60FL]
Precondition:
1. The residual voltage is measured via the residual voltage measuring
input.
2. Phase voltages are applied to the voltage measuring inputs (no line-
to-line voltages)
Calculation of the residual voltage is only possible, if phase voltages (star)
were applied to the voltage measuring inputs and
»VT con = phase-to-
neutral«.
Object to be tested
Check of the VT supervision (by comparing the calculated residual voltage with the measured one). It is to be tested
whether VE=3xV0.
Necessary means
4-channel voltage source (3+1)
Procedure, part 1
Set the limiting value of the VT supervision to
»
ΔV
=0.1*Vn«.
Feed a three-phase, symmetrical voltage system (nominal voltage) in to the secondary side.
Disconnect the voltage of one phase at one of the measuring inputs (symmetrical feeding at the secondary
side has to be maintained).
Make sure that the signal »VTS.A
LARM
« is generated now.
Successful test result, part 1
The signal
»VTS.A
LARM
« is generated.
Procedure, part 2
Feed a three-phase, symmetrical voltage system to the secondary side.
Feed a voltage of about 20% Un in to the measuring input of the residual voltage.
Make sure that the signal
»VTS.A
LARM
« is generated now.
Successful test result, part 2
The signal »VTS.A
LARM
« is generated.
539
MRU4
DOK-HB-MRU4-2E
