[sdiy] LinnDrum LM-2 power supply stuff

[Matthew Smith]

Quoth Eric Frampton at 10/08/11 09:00...
...
> Is there a universal way to test an xformer, aside from powering it up (a dodgy proposition by the looks of this one) and measuring voltage? 

Depends if you have or can beg/borrow/steal a Megger, or similar 
insulation tester. (Assuming the transformer has been disconnected.)

If I suspected that the insulation in a transformer might be 
compromised, this would be my approach. (I have an ancient, ex-military, 
500V Megger. Beautiful piece of equipment.)

Test winding to winding, each winding to core. If it didn't come up near 
infinite resistance, I'd be concerned.

I'd say the most likely problem (barring corrosion on the core or the 
outer shell) would be electrolyte creeping in to the wrapping tape and 
creating a path between the winding terminations.

Haven't seen what you've described, but have seen VERY rusty transformers.

Oh, and you could put low voltage AC on the primary and see if the 
secondary voltage is as you would expect.

Just my $0.02 worth - others will probably contradict me :-)

Cheers

M

-- 
Matthew Smith

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