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Cathode Ray · 28th Dec 2018, 10:27 pm

Folks,
I've managed to source a 2KVA variac and a 500VA isolation transformer.

What's the recommendation connection sequence?
I've seen people do it both ways.
Some have variac connected to the mains followed by isolation trafo on its output.
Others have the reverse, i.e. isolation connnected to mains.

I'm worried the large 10A variac could trip my mains fuse on power up (remenance effect), so would putting the 500VA (2 amp) isolation first minimise this risk ?

Thanks
Ray

28th Dec 2018, 10:27 pm	#1
Cathode Ray Pentode Join Date: Dec 2018 Location: County Meath, Ireland Posts: 242	Variac first or Isolation first ? Folks, I've managed to source a 2KVA variac and a 500VA isolation transformer. What's the recommendation connection sequence? I've seen people do it both ways. Some have variac connected to the mains followed by isolation trafo on its output. Others have the reverse, i.e. isolation connnected to mains. I'm worried the large 10A variac could trip my mains fuse on power up (remenance effect), so would putting the 500VA (2 amp) isolation first minimise this risk ? Thanks Ray