hi guys

it's great to discuss some of this issues with people with more knowledge like you..i previously read more about ct's and it seemed like you were mostly concentrating on the secondary side part. please lets try to cover both sides..my question is what happens when a primary side of the tx is left open/not connected?

 

Since the primary is normally powered by burden and the secondary is usually passive or instrumentation, not much happens when there is no primary current. It's effectively off.

Regards
cww

 

<i>my question is what happens when a primary side of the tx is left open/not connected?</i>

When the primary side is not connected, the CT itself is un-energized, and doesn't give any reading in the secondary.

The CT is supposed to be connected in series with the load. So if you just disconnect the CT, your load circuit will be broken! If you short-circuit the CT primary terminals, normal load current will resume, but the CT will not sense anything.

Yeasir Rahul
http://www.voltsmith.com