Arbiter Systems 931A, Operation Manual

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The selected phase preference effects only the displayed phase angle, but
none of the power quantities.
Press the MENU key and select Phase Preference (Section 3.3.1.13)
to set the phase preference. Table 3.8 describes the four possible phase
settings and the resultant displays for each, when the signals, shown in
Figure 3.13, are applied. See Section 3.6 for input connection description.
Range Polarity Setting Resultant
Setting for Ch 2 lagging Ch 1 Reading
±
180
◦
negative -60
◦
±
180
◦
positive +60
◦
0
−
360
◦
negative 300
◦
0
−
360
◦
positive 60
◦
Table 3.8: Phase Convention
Figure 3.13: Phase Angle Example
3.6.2 Active Power – Reactive Power
The Model 931A can measure the active power (rms watts) and reactive
power (vars) from the combination of an AC voltage routed to measure-
ment Channel 1 and an AC current routed to Channel 2.
NOTE: Refer to Section 3.6 for input connection description.
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