How to test psu

[123hotchef]

eBay item 283014069259 seems to have slightly shorter legs, which will need to be straightened out first, but otherwise OK as a replacement. There should be no need to solder extra legs, which would make it a fiddly job. With shorter legs, the regulator heatsink may clash with the main capacitor, though, so it might need to be soldered in on the pi**. A solder sucker or desoldering braid will be useful.

Thanks mr @voipio new regulator soldered in and she is back in full flow! You know your stuff! I didnt realise that if the amps go above the 3amp rating the unit switches over to 6V I guess to protect itself.

 

[123hotchef]

Heat sink fits just fine too

 

[voipio]

Excellent. The output reduction on overload will be down to foldback current limiting. The diagnosis was helped by the good clear photographs, and observations. Just don't ask about repairing switched mode power supplies. They're a completely different ball game.

 

[123hotchef]

Excellent. The output reduction on overload will be down to foldback current limiting. The diagnosis was helped by the good clear photographs, and observations. Just don't ask about repairing switched mode power supplies. They're a completely different ball game.

I wont ask about my other thread lol

 

[Seadog]

All you need now is a stiff brush and some IPA to wash the flux off.

 

[123hotchef]

All you need now is a stiff brush and some IPA to wash the flux off.

ah is that the secret thanks too late is back together will the flux eat the copper away

 

[Seadog]

No, you'll be fine. That is, unless you used plumbers' flux

 

[123hotchef]

No, you'll be fine. That is, unless you used plumbers' flux

lol no it was flux cored solder mate the easy stuff

 

[123hotchef]

Ok if I have 2 12v power suppys on my rust tank and wire them both up with lamps in the circuit to limit.the draw to 1.5amps each will.this work and give me 3 amps I can't work out

 

[Seadog]

In parallel, yes.

 

[123hotchef]

In parallel, yes.

but will the 2 power supplies get confused or any thing?

 

[Seadog]

Try it and see, but I don't think there'll be any issues. If you're worried you could insert a diode to isolate the supplies.

 

[123hotchef]

Try it and see, but I don't think there'll be any issues. If you're worried you could insert a diode to isolate the supplies.

ill give it a go tonight thanks

 

[voipio]

If both PSUs have foldback current limiting then, when they are both delivering close to their limit, one will go into current limit first, then the other, after which what will happen depends on the load, but could include them both repeatedly going in and out of current limit.

How about going for an adjustable bench power supply capable of around 5-10A. Not hugely expensive off eBay. Just search for "30V 10A power supply" if the link has expired. Very useful for lots of things, including charging batteries, electrolysis tanks.

https://www.ebay.co.uk/itm/292587524108

 

[123hotchef]

If both PSUs have foldback current limiting, when they are both delivering close to their limit, one will go into current limit first, then the other, after which what will happen depends on the load, but could include them both going in and out of current limit. How about going for an adjustable bench power supply capable of around 5-10A. Not hugely expensive off eBay. Just search for "30V 10A power supply" if the link has expired.

https://www.ebay.co.uk/itm/292587524108

i will stick a 12v lamp in that limits the current to 1.5amps in my electrolysis tank with them both limited to that 3amps will be perfect

 

[123hotchef]

she is now running duel psu at 12v putting out 2.7 amps I am happy with that

 

[123hotchef]

guess what @voipio it seems to have killed another regulator!

 

[voipio]

Hmm. Is it the same PSU as before, or the other one? .... You know that eBay link from the other day? ;-)

 

[123hotchef]

Hmm. Is it the same PSU as before, or the other one? .... You know that eBay link from the other day? ;-)

same psu mate I have soldered the other reg in as I got a pack of it all works again but i am no longer using them on the rust tank the computer psu is on there now instead chucking out 7amps and not even getting warm its like day/night why I didnt get one sooner!