Isolation transformer consumption

[mathk]

Hi

Dave often talk of isolation transformer for safety reason when you are probing a device.
But I am concern about if you install such transformer will it consume power when nothing is connect to it?

Thanks

[Monkeh]

Well, yes, a little, so, y'know, turn it off.

[TriodeTiger]

I would have to throw in some terms such as core losses, those may draw power even though the transformer is not connected to anything.

A switch may be the better way, or buying an inexpensive energy meter and seeing if it is reasonable!

[mathk]

Ok I see thanks for the precision. A simple switch will it work?  I thought that since it is a coil, open a close circuit that have coil can generate some spike?

[Monkeh]

Ok I see thanks for the precision. A simple switch will it work?  I thought that since it is a coil, open a close circuit that have coil can generate some spike?

So how do you switch any transformer load?