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Uncle Bulgaria · 5th Feb 2019, 4:45 pm

You were right Lawrence - my error was checking the secondaries, when in fact I was using the wrong primary windings as one is on the other side of the transformer.

New values are 46R5 Rp, and a 1:2.5 ratio (30V at 12V), which gives an Rt of 282R6.

If 240VAC is across the primary, and 600V across the secondary, then according to the datasheet that's 2x300V which needs a minimum Rt of 215R. So it's in tolerance.

Correct?

5th Feb 2019, 4:45 pm	#27
Uncle Bulgaria Nonode Join Date: May 2016 Location: Cornwall, UK. Posts: 2,338	Re: Ferrograph 4A: Restoration advice needed You were right Lawrence - my error was checking the secondaries, when in fact I was using the wrong primary windings as one is on the other side of the transformer. New values are 46R5 Rp, and a 1:2.5 ratio (30V at 12V), which gives an Rt of 282R6. If 240VAC is across the primary, and 600V across the secondary, then according to the datasheet that's 2x300V which needs a minimum Rt of 215R. So it's in tolerance. Correct?