Operating instructions

General Description SW 5250A•SW 3500A•SW 1750A
1-8 Operation Manual
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Valid for phases A, B, C, and TOTAL (use phase A for Parallel Mode).
The Power Factor is calculated from the Power and VA measurements. Phase powers
are measured then the total power is calculated; phase VAs are measured then the
total VA is calculated. Power is divided by VA; the result is the Power Factor.
Range: 0 to 1.00.
Accuracy: ±5% of range at full power, DC or 40 to 500 Hz for crest factors <2.0.
Add ±2% for crest factors up to 4.0. Add ±1%/kHz above 500 Hz.
Temperature Coefficient: ±500 ppm/°C outside specified range.
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Frequencies are calculated based on output zero crossing time measurements. To
minimize errors due to switching noise, a 1 µs filter is used to filter the output signal
before the zero comparator.
Resolution: Frequency is displayed to 5 figures maximum; the leading zeros are
blanked. Displayed resolution is 0.01 Hz.
Accuracy: ±0.5% of reading, at 10% to full output voltage, 0°C to 45°C
(32°F to 113°F).
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Valid for phases A, B, and C relative to each other.
The phase of measured signals are calculated from timing measurements. The
reference is the negative to positive zero crossing of the internal reference (sync pulse)
signal. End of timing is the negative to positive crossing of the signals being measured
with respect to the internal reference. These timing measurements are used to
calculate the phase lead between the two phases being measured.
Resolution: ±1° (for outputs above 20 VRMS).
Accuracy: ±2°, 40 to 500 Hz; add ±2°/kHz above 500 Hz.
For sine wave, balanced resistive load, 10% to 100% of voltage measurement range.
All accuracies are specified for 0°C to 45°C (32°F to 113°F).