What test should do for Current Transformer( CT)?

Current transformers are divided into metering current transformers, protective current transformers, zero-sequence protection current transformers, etc. 

They are transformers designed for different purposes. For metering current transformers, they are mainly used for electrical power measurement. It need to measure parameters like  angle error,Ratio polarity,Magnetizing Characteristic,Interturn withstand voltage, as well as secondary loop test ,demagnetization test at field.

Current Transformer demagnetization test

When the opening method is demagnetized, a winding of a number of turns at a time (or second) winding is selected at a rated (or secondary) current, and in the case where other windings open, Steady and slowly reduce the current to zero, the peak voltage meter connected to the maximum number of turns should be monitored during the demagnetization. When the indication value reaches 2600V, the current value should be demagnetized.

When the closed-path method is performed, a resistor equivalent to a rated load is 10 to 20 times (considering sufficient capacity) on the secondary winding (considering sufficient capacity), the primary winding is transmitted with a power frequency current, from zero to 1.2 times the rated current, and then uniform Slowly down to zero.

If the core of the current transformer is around two or more secondary windings, one of the secondary windings is retired when retreats, and the remaining secondary winding opens.

Note: When metering current transformer is measured, the appropriate standardizer and measurement equipment are required in accordance with the accuracy level and verification procedure of the detected current transformer.

The current transformer's test items are still cumbersome. If encounter problems during the test, you can always consult us,and we will reply you ASAP