On Thu, 13 May 2021 20:37:35 +0100, Clive Arthur
wrote:

On 13/05/2021 17:00, Theo wrote:
T i m wrote:
I still have one of the game console PSUs that I bought after a 'heads
up' from someone here, and a stripped out PC PSU but on that the 12V
is only 16A, and neither will fit under the printer and whilst I
thought it being there wasn't 'a good idea', it actually helps keep
all the power cables short and the PSU within the constrains of the
printer itself without getting in the way.

Probably me.

The open frame ones are on ebay:
https://www.ebay.co.uk/itm/164357507368
You can also get them in power brick form:
https://www.ebay.co.uk/itm/293813499442

although who knows what the quality is like.

Theo

'Meanwell' PSU's seem to be pretty good quality and value. Lots on eBay.

Thanks Clive, they do seem to be a step above the basic offerings, or
should do by the price of some of them. ;-)

The only one SP-200-12that looks like it's the same width as the
existing is only 200W / 16A, and that's a bit less than the 20A of the
original. However, the chances are the Meanwell is a real 16A versus
the cheapo and given *that* lasted for a good 5+ years ... ?

We know the 3D printer heated bed draws ~10A (on 12V) but can also run
on 24V and so would be nearer to 5A on 24V. If replacing the caps
(ordered) doesn't sort the old PSU, I was thinking I could use a
SP-200-12 for the 12V stuff and a 24V (10A indicated, assuming it's
only 7) PSU for just the Bed Heater.

Originally is was being driven by a Mosfet on the main board but the
FET got very hot so I used the FET to drive a 12V 40A automotive relay
and that seems to have worked ok (bang-bang). That means I could
easily set the heated bed up for 24V and use the same relay (still
driven by 12V on the coil).

I tested all 4 caps and they all came out ok (on my little component
tester) but I'm wondering if it might be different under real load /
voltage (or why would one cap be bulged and the PSU not working
properly)?

Cheers, T i m