Why Does Reconnecting the Secondary Winding Affect Current Transformer Output?

[anabanana]

i can't seem to understand why with current transformer if the primary winding is reconnectable the rated output stays the same. but rated output depends on turn ratio if the secondary winding is reconnectable??
why??

 

[Bob S]

I don't really understand your question, but here is what I know about current transformers.

For monitoring ac currents, the primary is usually a single turn through a toroid. The N-turn secondary, if shorted or terminated in a resistive load, will have 1/N times the primary current. Shorting the secondary does no damage to the transformer. The current in the secondary opposes the primary current, and prevents the toroid magnetic core from going into saturation (too high a dB/dt). There is usually a maximum volt-seconds limit on the output.

For monitoring dc currents, the toroid has to have low permeability to prevent core saturation (B_max > 1 Tesla) at maximum primary current. To monitor the dc current, the voltage output (into a high impedance termination) should be integrated in a good low-leakage op-amp integrator wilth a low-leakage capacitor in the feedback loop. See voltage integrator design in
http://www.matthewmassey.com/RogowskiCoil/
Bob S

 

[oswaler]

This is because the rated output of a current transformer is determined by the primary winding and the core material, not the secondary winding. The primary winding is responsible for creating a magnetic field that induces a current in the secondary winding. The turn ratio only affects the secondary current, not the rated output. Therefore, if the primary winding is reconnectable, it does not affect the rated output as long as the same core material is used. However, if the secondary winding is reconnectable, it can change the turn ratio and therefore affect the secondary current, but not the rated output.

 

[oswaler]

The rated output of a current transformer depends on the turn ratio, regardless of whether the primary or secondary winding is reconnectable. This is because the turn ratio determines the amount of current that is stepped down or up in the transformer. If the turn ratio remains the same, the output will also remain the same. However, if the secondary winding is reconnectable, it can be connected in different configurations, which can change the turn ratio and therefore the output. It is important to carefully consider the turn ratio and the configuration of the secondary winding when using a current transformer to ensure accurate measurements.