Woodward SEG HighPROTEC MRA4, Device Manual

Page: 473 / 510

VTS-Supervision Module - Voltage Transformer Supervision [ANSI 60FL]
Commissioning: Voltage Transformer Failure [ANSI 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« and »EVT con=calculated« were set in the field parameters.
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 (nominal current).
•
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.
EN MRA4 04/09 Page 473