Arbiter Systems 931A, Operation Manual

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These adjustments can compensate for phase or amplitude error,
and account for the ratio of a CT or PT.
Amplitude and phase scale factors may be entered for:
ˆ
Each of the three current inputs;
ˆ
Each of the three voltage inputs relative to neutral;
ˆ
The three voltage inputs relative to each other.
Use the store SETUP FUNCTION described in Section 3.3.2.16 to
store global PT and CT scale factors (not individual) for later retrieval.
The following assignments are made:
Set Scale: Auto Sets: Set Scale Auto Sets:
Van Vas, Vb Vbc Vcb
Vbn Vbs Vca Vac
Vcn Vcs Ia In
Vba Vab
SCALE does not allow scale factors to be entered for DC
measurements.
Press SHIFT > SCALE to view Scale Factor Gain and Phase Selections.
The display then shows the magnitude and phase scale factors for each of
the input functions as seen below.
For magnitude, the factor represents the number by which a measured
value is multiplied during the measurement process. For example, a
magnitude scale factor of 100, with 10 volts applied to the Model 931A
input, displays 1000 volts.
Therefore, if the Model 931A was used to
measure the voltage at the output of a 100:1 PT, and the magnitude scale
factor was set to 100, the display would show the actual voltage value
present at the PT input (compensating for the 100:1 reduction of the PT).
Valid range for Scale Factors is 999999 to 0.0001.
Apply global PT and CT scale factors and simplify operation when
desiring to use a PT or CT on any input. For example, press SHIFT >
SCALE, then select PT with the cursor, then press ENTER. Using the
cursor, select the appropriate digit, or decimal point, using the right and
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