Polarity Marks on CT's 2

[recs]

Does anybody know a detailed guide for polarization marks in current transformer relays?

I understand how the polarization marks work when the primary CT current ENTERS the primary CT and the polarization mark of the primary CT is at the entrance (begining of the coil. But I do not uderstand when the primary CT polarization mark and secondary CT polarization mark are AFTER the CT and the primary CT current reachesthe polarization mark after leaving the CT.

Thanks.

 

[davidbeach]

Current into the primary polarity produces current out of the secondary polarity. Current out of the primary polarity produces current into the secondary polarity.

Now forget polarity marks:

Current into one end of the primary produces current out of the same end of the secondary while current out of one end of the primary produces current into the same end of the secondary.

Don't get hung up on the polarity marks, look at how the CT is in the circuit, where the secondary is grounded, and how it connects to polarity of the relay. Relay polarity matters, CT connections and orientation matter, but actual placement of the CT polarity doesn't.