Whenever I have carried out a mag curve I have always been told to drive it into saturation (1A through the secondary), bring it down slowly to 0 then plot various points up to the knee point and carry on all the way up to complete saturation again. The other day I got into a heated discussion...
I know it shouldnt be removed but what if the person you are working with has taken the earth link up to megger it then forgot to put it down, then without knowing you pressure test the switchgear. So as for not needing to remove the ground, under commissioning you do to prove it (and if your...
Many thanks for that.
Gunax, I wasnt testing the CT itself I was pressure testing the HV switchgear, theres no way of doing this without passing HT through the CT on this particular gear. We got talking as to the do's and donts and I said I wasnt sure what would happen if the CT was open circuit...
thanks, as a rule I always do short and ground them, im just curious what happens if you dont. Like you say there would be no current flow but would the CT start to behave like a VT and generate a huge secondary voltage?
Hi, Ive read all the posts on open circuit CT's already but they all refer to what happens when primary current is applied to them. My quick question is what happens in a power frequency withstand test, with the secondary open circuit, i.e. 11kV AC applied to primary conductor. Anyone?