John Rumm wrote:

On 13/11/2017 20:38, Roger Hayter wrote:

It seems he already has as much electrical heating as that
autotransformer will ever supply, and is probably exceeding its ratings.
Perhaps someone who knows where it is could have a quick look and see if
any smoke comes out when the voltage drops to 202V?

ISTR that bigclive did a tear-down on one of those voltage reduction
units. At some load point it actually had relays to bridge itself out of
the supply as a self protection mechanism. So you may find enough load
actually takes it out of circuit.

That sounds a sensible arrangement, But doesn't the marked voltage
drop make it a bit unlikely?

--

Roger Hayter