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Diabolical Artificer · 17th Jun 2018, 3:53 pm

Only had one busted valve when posting etc Mike, but that was down to bad packing. If you pack them right you should be ok, but will leave it up to you. The last lot of 813's I got came in plastic PVC pipe, cracking packing.

"With winding voltages up to 195, then 1N4007 diodes will be plenty." But it's the 1kv DC present I'm worrying about. Thing is how is over voltage measured in regards to the datasheet spec for a diodes DC breakdown voltage? The +1kv isn't present across the two diodes of the positive side of the bridge. The highest potential I guess is across two diodes, which would mean DC breakdown voltage is doubled, as the DC across the cap, here a tad less than 270v is all that par of the bridge sees.

Probably tending to over think things here, it's easy to fret though when such high voltages at quite high current are present.

Anyhoo, I'll do some testing, been out today so not had chance.

Andy.

17th Jun 2018, 3:53 pm	#7
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,658	Re: Testing 813's. Only had one busted valve when posting etc Mike, but that was down to bad packing. If you pack them right you should be ok, but will leave it up to you. The last lot of 813's I got came in plastic PVC pipe, cracking packing. "With winding voltages up to 195, then 1N4007 diodes will be plenty." But it's the 1kv DC present I'm worrying about. Thing is how is over voltage measured in regards to the datasheet spec for a diodes DC breakdown voltage? The +1kv isn't present across the two diodes of the positive side of the bridge. The highest potential I guess is across two diodes, which would mean DC breakdown voltage is doubled, as the DC across the cap, here a tad less than 270v is all that par of the bridge sees. Probably tending to over think things here, it's easy to fret though when such high voltages at quite high current are present. Anyhoo, I'll do some testing, been out today so not had chance. Andy. __________________ Curiosity hasn't killed this cat...so far.