7-34
Section 7: Model 9100: Specifications
Final Width = 215mm
It is clear that at lower power factors the contribution from the Phase Uncertainty dominates. This demonstrates why most
calibrations are performed at Unity Power Factor (0
°
phase difference between channels). The following table illustrates the
amplitude uncertainties introduced due to a phase difference. The user can optimise the total power uncertainty by calibrating at
higher power factors.
Corresponding
Channel Phase
Amplitude Uncertainty due
Power Factor
Difference
to Phase*
Voltage <105V
Voltage >105V
Current <20A
Current <20A
1
0
°
0.0003%
0.0009%
0.95
18.19
°
0.0864%
0.1385%
0.90
25.84
°
0.1271%
0.2037%
0.86
30.00
°
0.1515%
0.2427%
0.80
36.87
°
0.1967%
0.3150%
0.70
45.57
°
0.2674%
0.4282%
0.60
53.13
°
0.3494%
0.5594%
0.50
60.00
°
0.4538%
0.7264%
0.25
75.52
°
1.0141%
1.6229%
* For Calibrator output <65Hz