Variac in nice metal case - UK Vintage Radio Repair and Restoration Discussion Forum

dragonser · 26th Mar 2019, 1:25 am

Hi, I got the following which I thought was a variac in a case. However when I took the back plate off I found there was a Gardiners transformer giving up to 15 volts ac at 200va. I just wondered if anyone recognised it ? There are some wires not connected, so I will have to copy the circuit diagram out.

FIXITNOW · 26th Mar 2019, 8:43 am

looks like the variac is just adjusting the 240 I/p voltage to the 15v transformer to give a low voltage AC psu 0 -15v a bit of rework and you could have a standard variac if you find a 270v AC meter

turretslug · 26th Mar 2019, 10:45 am

Looks like a potentially (!....) useful combo there- the option of bringing the 0-270VAC out for external use, plus switching it into the transformer for a high current, low voltage variable supply with AC or bridge-rectifier/roughly smoothed DC option- if nothing else, the sort of thing for putting a monitored dose of DC current into a car battery for those click-dim-nothing winter mornings....

A variac, a meaty transformer, a sturdy case with room to spare and a nice big meter- excellent starting point. I assume it was something like an educational supply originally?

Skywave · 26th Mar 2019, 11:03 am

Quote:

Originally Posted by turretslug

. . if nothing else, the sort of thing for putting a monitored dose of DC current into a car battery for those click-dim-nothing winter mornings....

"click-dim-nothing winter mornings": very eloquently & succinctly put & so very descriptive! I think that many of us have 'been there'!

Al.

Refugee · 26th Mar 2019, 2:25 pm

We had 30V 30A variac power supplies at college in the old days.
We used them for fuse blowing tests along with those white smiths timers that looked like alarm clocks without the bells on top. We plotted graphs of time against overload.
I have got a 25 volt door stopper transformer that I use with a regular variac for heavy duty low voltage work.

26th Mar 2019, 1:25 am	#1
dragonser Heptode Join Date: Aug 2009 Location: Carshalton, Surrey, UK. Posts: 735	Variac in nice metal case Hi, I got the following which I thought was a variac in a case. However when I took the back plate off I found there was a Gardiners transformer giving up to 15 volts ac at 200va. I just wondered if anyone recognised it ? There are some wires not connected, so I will have to copy the circuit diagram out. Attached Thumbnails __________________ Regards Peter B

26th Mar 2019, 8:43 am	#2
FIXITNOW Octode Join Date: Feb 2007 Location: Ely, Cambridgeshire, UK. Posts: 1,976	Re: Variac in nice metal case looks like the variac is just adjusting the 240 I/p voltage to the 15v transformer to give a low voltage AC psu 0 -15v a bit of rework and you could have a standard variac if you find a 270v AC meter

26th Mar 2019, 10:45 am	#3
turretslug Dekatron Join Date: Nov 2011 Location: Surrey, UK. Posts: 4,397	Re: Variac in nice metal case Looks like a potentially (!....) useful combo there- the option of bringing the 0-270VAC out for external use, plus switching it into the transformer for a high current, low voltage variable supply with AC or bridge-rectifier/roughly smoothed DC option- if nothing else, the sort of thing for putting a monitored dose of DC current into a car battery for those click-dim-nothing winter mornings.... A variac, a meaty transformer, a sturdy case with room to spare and a nice big meter- excellent starting point. I assume it was something like an educational supply originally?

26th Mar 2019, 2:25 pm	#5
Refugee Dekatron Join Date: Apr 2012 Location: Worksop, Nottinghamshire, UK. Posts: 5,554	Re: Variac in nice metal case We had 30V 30A variac power supplies at college in the old days. We used them for fuse blowing tests along with those white smiths timers that looked like alarm clocks without the bells on top. We plotted graphs of time against overload. I have got a 25 volt door stopper transformer that I use with a regular variac for heavy duty low voltage work.