Current Transformer Polarity Test
Polarity in a current transformer means the secondary terminals are marked so that current direction is known: when primary current enters the marked primary terminal, secondary current leaves the marked secondary terminal. If polarity is reversed, differential protection sees a fault where there is none, and directional metering reads backwards.
CT analyzers in the manufacturer's range test polarity together with ratio, burden and excitation. The GF1061CT and the GF106 family both list polarity testing among their functions. Primary injection testing also reveals polarity, because the secondary current direction can be observed while primary current is injected.
Polarity should be checked at installation and after any wiring change, not only at commissioning. A record should state the transformer identification, the terminal markings as found, the test method, and the result. Where markings are worn or unclear, photograph the terminals and the nameplate before testing, so the as-found condition is preserved.
Before ordering, confirm the transformer types, whether polarity testing is included in the analyzer functions, and the delivery terms. Ask for the current datasheet to be confirmed in writing before ordering.
Figures on this page come from the manufacturer's own category pages, manufacturer-hosted datasheets, or a shop listing stated as such. Where the reference material does not settle a figure, this site states that it is unresolved and publishes no figure, rather than choosing one.
What to confirm before ordering
Before payment, confirm the model, the specification from the current datasheet, the quantity, the price, the lead time, and the delivery terms, in writing. Ask in your inquiry to confirm the payment terms, the trade terms, and the reply time you should expect, rather than assuming any of them. No price, minimum order or lead time figure is stated on this site.
Send an inquiry: include the model, the test or measurement requirement, and the quantity you need. Before payment, confirm the model, the specification from the current datasheet, the quantity, and the delivery terms.