When the power current transformer is wound, the current ratio of the transformer should be determined according to the size of the load, and then the primary line should be wound from the center of the transformer according to the request. Note that the number of turns around the outer ring should not be the number of windings. The number of turns that penetrate into the power current transformer is taken as the standard.
The power current transformer model is composed of 2 to 4 digits of pinyin letters and numbers. Generally, the coil type of the power current transformer, the type of insulation, the material of the conductor, and the place of use can be expressed. The number after the horizontal line indicates the voltage level of the insulation structure.
The wiring of the power current transformer should follow the principle of series connection: the primary winding should be connected in series with the circuit under test, and the secondary winding should be connected in series with all instrument loads; according to the current measured, select the appropriate ratio, otherwise the error will increase. In order to prevent the busbar fault caused by the strut-type power current transformer casing flashover, the power current transformer is usually arranged on the outlet or transformer side of the circuit breaker.