ECN Forum Forums General Topics of the Trade General Discussion Area Transformers: mind-boggling, mysterious beasts

Long story short,

The Secondary side of the Isolation Transformer being used (between the VARIAC and the load item) is not Grounded - therefore it offers an isolation, so there is a reduced hazard for a shock to ground.

Getting caught between the two output leads of the Secondary still gives the "Barbequed Effect" to whom ever is unlucky enough to be the Conductor.

In reality, there will still be a potential to ground through the isolation transformer (with an ungrounded secondary side).
The potential ("Voltage") is a result of Capacitive Coupling, and will vary with distance.

Also, if the Primary Winding faults into the Secondary Winding - either through a loss of smoke (extended overload scenario), or flash-over scenario, the resultant connection becomes an Autotransformer - which both eliminates the Ground Isolation safety thing, and increases the Voltage on the Secondary side.

Do a search on this site for threads regarding operational characteristics of Transformers, Inductors and AC Generators.
We have had many such in-depth talks regarding the basics through the extremes of these beasts.

Do searches in the General area, the NEC area and the Technical Reference area.

One very important point of safety regarding Transformers:

Don't drop them on your foot! That really hurts!

Good luck!

Scott35