CT's are low frequency devices, typically 50-400Hz. At high frequencies their phase shift will
cause the power measurement to be in error.
CAUTION!
When using CT's, never open-circuit their secondary while power is applied The CT will act
like a step-up transformer and may produce lethal voltages which can damage the operator
and/or the power analyzer.
Figure 5-3 illustrates the basic method of connecting a CT to a digital power analyzer.
Figure 5-3 | 2105 Connections using a CT
Figure 5-4 | 215 Connections using a PT
5.4.2.2
Potential Transformers
Potential transformers (PT's) are used to extend the voltage measurement capabilities of Valhalla digital
power analyzers. PT's are available in many ratios, maximum voltage ratings and isolation voltages.
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