Manta MTS-1700 SERIES, Руководство по эксплуатации и справочник

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MTS-1720 TWO CHANNEL CURRENT SOURCE - Section 9
MTS-1700 SERIES OPERATION AND REFERENCE MANUAL 9-11
CU A002 15A
MANTA TEST SYSTEMS
9.4 THREE-PHASE CURRENT OPERATION (I3-WYE CURRENT MODE)
9.4.1 Important Fundamentals
When I3 current mode is selected on the MTS-1710, and the MTS-1720 is available, the current mode
changes to “I3-WYE”, annunciated in the lower right hand corner of the [MODE/MENU DISPLAY]. True
3
Φ
current is now available.
Three-phase testing is greatly simplified by the MTS-1710/MTS-1720 system. Some important
fundamentals of this system are described below.
•
Intelligent phase/amplitude control for simulating standard faults.
The concepts of 3
Φ
voltage manipulation simply have been extended to apply to 3
Φ
current.
The user can simulate standard faults by adjusting only three settings: the fault voltage, fault current,
and phase angle between the two. The MTS-1710 intelligently sets all other phase angles and
amplitudes.
For faults involving more than one phase, the fault voltage, fault current, and fault phase angle are
automatically applied to the appropriate phases. The MTS-1710 sets all unfaulted phases to their
prefault amplitude and phase angle.
•
Direct phase angle control/display.
The phase angle between the fault phase voltage and current is always displayed, regardless of the
selected fault mode. For example, if
Φ
-
Φ
A-B fault mode is selected, the phase of Vab referred to Iab
is displayed.
If
Φ
-N C-N fault mode is selected, the phase of Vc referred to Ic is displayed. This means that, when
testing phase angle sensitive elements, the MTA always can be displayed directly.
In prefault state, phase angle adjustments affect all three phases of current simultaneously. In fault
state, phase angle adjustments alter only the phase angle of the currents participating in the fault.
•
Direct measurement of line or phase currents.
The appropriate line current (Ia, Ib, Ic), or phase current (Iab, Ibc, Ica), is measured and displayed
based upon the selected fault mode.
•
Memory of fault settings.
The MTS retains values of
Φ
-N,
Φ
-
Φ
, 3
Φ
and 2
Φ
-N fault voltage and current.
The fault settings can be applied to successive relay elements of the same type simply by rotating the
[FAULT PHASE] selector. For example, if a 2
Φ
-N fault is set up for A-B-N, the identical conditions
can be applied to B-C-N and C-A-N by rotating the [FAULT PHASE] selector to these positions.