DETAILED OPERATION - Section 4
4-36
MTS-1700 SERIES OPERATION AND REFERENCE MANUAL
MANTA TEST SYSTEMS
CU A002 15A
Once the fault
Φ
-
Φ
voltage of 40V is set, it can be applied to any desired phase (A-B, B-C, or C-A) by
changing the [FAULT PHASE] selector. In addition, if I3 current mode is selected, the current path will be
a
Φ
-
Φ
path.
4.7.6.4
THREE-PHASE-TO-GROUND FAULT EXAMPLE.
To simulate a three-phase-to-ground fault, set up the following voltages:
Fault mode Fault state Voltage
Φ
-N
A-N Prefault 70V
Φ
-N
B-N Prefault 70V
Φ
-N
C-N Prefault 70V
3
Φ
-(
Φ
-
Φ
) B-C Prefault 120V
3
Φ
-(
Φ
-
Φ
) B-C Fault
10V
4.7.6.5
THREE-PHASE-OVERVOLTAGE FAULT EXAMPLE.
To simulate a three-phase-overvoltage fault, set up the following voltages:
Fault mode Fault state Voltage
Φ
-N
A-N Prefault 100V
<-overvoltage value
Φ
-N
B-N Prefault 70V
Φ
-N
C-N Prefault 70V
3
Φ
-(
Φ
-
Φ
) B-C Prefault 120V <-nominal (prefault) voltage
3
Φ
-(
Φ
-
Φ
) B-C Fault 10V
4.7.6.6
TWO-PHASE-TO-GROUND FAULT EXAMPLE.
To simulate a two-phase-to-ground fault, set up the following voltages:
Fault mode Fault state Voltage
Φ
-N
A-N Prefault 70V
Φ
-N
B-N Prefault 70V
Φ
-N
C-N Prefault 70V
2
Φ
-N
C-A Prefault 120V
2
Φ
-N
C-A Fault 55V
Once the fault
2
Φ
-N voltage of 55V
is set, it can be applied to any desired phase (A-B-N, B-C-N, or C-A-
N) by changing the [FAULT PHASE] selector.
4.7.7
Voltage Adjustment with Unbalanced Systems
Voltage adjustments in the
Φ
-
Φ
fault types will collapse the appropriate
Φ
-
Φ
voltage to simulate a true
Φ
-
Φ
fault, even if the prefault
Φ
-N voltages are unbalanced. This is shown in Figure 4.26.
Similarly, for 3
Φ
fault types, 3
Φ
voltage adjust will be performed to keep the percentage voltage collapse
on all three phases equal, even if the prefault
Φ
-N voltages are unbalanced.