Im just reading about CTs, just for interest really. I have always known that you short CTs when they arent connected, but assumed it was just so you couldn't get a shock from the cable which would rise to the voltage on the cable its clamped around. I know this isn't quite right now.
Evidently, the voltage can rise to thousands of volts and damage the CT, I assume this happens instantly, rather than a gradual rise
The other thing, and this is my question really, if one side is grounded and commoned, as the drawings of them show, and the other side is open, does the voltage rise still occur? I just cant quite fathom it in my head