Sciencemadness Discussion Board

Corning PC-420 Transformer Replacement

Psychedelic_Monkey - 6-2-2020 at 00:35

I recently picked up a used PC-420 from ebay it was a 120v model, in my infinite wisdom after looking at the power connector I saw it read 240v. Unfortunately this was just what the socket was rated for and after about 5 mins of use I smelt that lovely burnt electronics smell and the transformer exploded.

I'm wondering if any of you guys know the specifications for the transformer or maybe have a broken hotplate lying around, I could not find any information looking up the numbers on the side. The only marking I could read was "HD35-12:5 A".

Any help is appreciated.

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Sulaiman - 6-2-2020 at 00:51

Before repairing the stirrer ... does the heating part still work ?
You are using 230 Vac instead of 110 Vac for both the transformer AND the heaing element.

Psychedelic_Monkey - 6-2-2020 at 01:32

I believe the transformer is required for the control circuitry for the heating element - so I cannot test if the heating mantle still works but the transformer clearly blew.

RedDwarf - 6-2-2020 at 01:38

Just test the continuity on the heating element, as Sulaiman says no point in replacing transformer if you've fried everything else as well.

Psychedelic_Monkey - 6-2-2020 at 01:43

Continuity is fine for each heating coil, I've checked pretty much every major component, I could only find a problem with the transformer.

Keftedes89 - 10-2-2020 at 23:34

Check your U2U. I can probably help if you are in the USA

G-Coupled - 11-2-2020 at 09:55

Quote: Originally posted by Psychedelic_Monkey  
Continuity is fine for each heating coil, I've checked pretty much every major component, I could only find a problem with the transformer.

K
Transformers, much like heating elements, can be repaired/rewound.

Quite often worth it if it's an oddball/ancient transformer model that's not available off the shelf.

Psychedelic_Monkey - 20-4-2020 at 18:11

I'm still looking for the part if anyone has one.

Dr.Bob - 21-4-2020 at 17:51

I'll keep a lookout, I have many parts for older Corning units, but not sure if I have any broken 420s, but I will look around for any.

Heptylene - 22-4-2020 at 15:39

Could you find an equivalent transformer? I assume the voltage outputs are pretty standard. I guess you'd have to deduce the voltage needed since the transformer doesn't work anymore, or have someone look inside their working PC-420 and measure the voltage. Do you have a picture of the circuit board?

G-Coupled - 22-4-2020 at 19:20

Yeah - that'd be a potentially really helpful bit of knowledge - if someone with a PC-420 could kindly measure the voltage coming out of the secondary windings of the transformer when it's in operation, then it would be trivial to work out its rating and possibly find a compatible generic replacement.

If the burned-out transformer is a simple, common one like a 120V-12V single tap, then you should have lots of choices to replace it with.

[Edited on 23-4-2020 by G-Coupled]