Arbiter Systems 931A, Operation Manual

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Displayed waveforms correspond to the input signals after
they have been digitized and subjected to digital low-pass filtering. The
display includes all components of the signal up to 3.05 kHz.
The waveform display is normalized to positive going zero crossings of
Channel 1 signal fundamentals. To inspect the current waveform, reference
the current at Channel 2 to the voltage at Channel 1.
The displayed
waveform amplitude is relative to the displayed percentage of the selected
range.
View waveforms individually by pressing CHANNEL 1 SELECT, or
CHANNEL 2 SELECT, with the waveform display active.
3.3.1.7 Channel 1 Select
CHANNEL 1
SELECT
NARROW-BAND
Press the CHANNEL 1 SELECT key to view the input config-
uration menu for Channel 1.
Always connect the lowest distortion input signal to Channel
1 since it is used as the internal reference. For most power
systems the voltage has lower distortion than the current. If
applying only one signal, it must be connected to Channel 1.
If analyzing a single highly distorted waveform connect a reference signal
of the same fundamental frequency to Channel 1 and the waveform to be
analyzed to Channel 2.
Combinations from the front panel inputs allow twenty-seven choices;
three AC currents (A, B, C); twelve AC voltages, and twelve DC voltages.
Each voltage terminal may be referenced to any other voltage terminal,
to the front-panel neutral, or (for AC) to a synthesized neutral, which is
the average of “Va”, “Vb” and “Vc”. Tables 2.1 and 2.2 list the possible
input combinations.
3.3.1.8 Channel 2 Select
CHANNEL 2
SELECT
BAND-WIDE
Press the CHANNEL 2 SELECT key to select the input con-
figuration menu for Channel 2. Front panel input combinations
allow twenty-eight choices; four AC currents (A, B, C, N); twelve
AC voltages, and twelve DC voltages.
The Neutral Current
“N” is minus the vector sum of “Ia, Ib, and Ic”. Each voltage
terminal may be referenced to any other voltage terminal, to
the front-panel neutral, or (for AC) to a synthesized neutral, which is the
average of “Va”, “Vb” and “Vc”. Tables 2.1 and 2.2 list the possible input
combinations.
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