What would happen to the measured values of a circuit (real power, apparent power, power factor, current) if I install a current transformer "backwards"?

Usually a current transformer has some markings on its external casing (usually an arrow or text) indicating which side the source (generator, etc) must be regarding the transformer.

I googled a little and while I found that installing the current transformer backwards would result in negative current/power/consumption, nowhere stated what would happen to the power factor/apparent power/real power.

The background for this question is that I recently took charge of an installation having many circuits being measured (mostly single-phase 240V) and a few of them seem to be getting strange readings, like a pitiful power factor of -0.25 instead of something around +0.70, and apparent power of around 1000 VA instead of around 500 VA.

While I know that the meter per se is working fine, I suspect someone installed or connected one or more of the current transformers backwards. And unfortunately, for the time being, I won't be able to change anything in the installation (for now) since the panels are hard to access.

Thanks in advance.

  • \$\begingroup\$ Just for clarification, I want to know what I should expect to get as readings for a known circuit if the only change effected is reversing the current transformer. \$\endgroup\$ – Flyingfenix Apr 18 at 18:46

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