Pacific UPC-12, Operation Manual

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SECTION 2 SPECIFICATIONS
15
2.2.7 WAVEFORM ANALYSIS (cont’d)
The harmonic data is reported using a sine series with coefficients expressed in polar format (magnitude
and phase angle).
Each magnitude percentage is referenced to the fundamental which is always defined as having a
magnitude of 100%.
*
NOTE : 1. When analyzing load current or voltage, use as much of the meter range as possible.
The specifications given apply to measured waveforms in which the peak values are at
least 20% of the meter range. Valid results can be obtained from lower magnitudes, but
accuracy of the higher order harmonics will deteriorate.
2. Phase angle accuracy is a guideline value only. It cannot be precisely stated
because it varies greatly with waveform type and magnitude. In general, it is most
accurate with quasi-sinusoidal waveforms, and poorest with pulse type waveforms and
those containing many discontinuities, when resolving high order harmonics.
2.3 ELECTRICAL INTERFACE
2.3.1 ISOLATION
The UPC contains one isolated power supply for all circuits. The REMOTE interface is NOT isolated
from the CPU or oscillator sections. The UPC's circuits may float with respect to GND but this is not
recommended. In the Power Source, provision is made at one location to tie power supply common to
GND. The user may establish their own local ground by removing the link from power supply common
and GND.
2.3.2 INPUT POWER
The System Control Unit (SCU) will operate from 115 or 230 VAC, 47 to 440 Hz. Conversion is made by
a recessed switch on the back of the SCU. Input protection is a front panel circuit breaker.
The UPC controller r10 Vdc and ±20 Vdc at J6. This is supplied by the SCU or Power Source in
which the UPC is installed.
2.3.3 ANALOG OUTPUTS
The oscillator waveform ( Φ A, Φ B, Φ C) differential outputs are available on J3. They are capable of
driving full output of ± 10 V
peak
into a 600 ohm load.