On Thu, 13 May 2021 22:24:15 +0100, Peter Able wrote:

On 13/05/2021 22:46, T i m wrote:
On Thu, 13 May 2021 21:27:03 +0100, Peter Able wrote:

snip

That's an odd place to put the fan.

Agreed.

https://ibb.co/3FZYMPP

Sure looks like there's been some cooking and boiling !

Yeah, that ferrite was quite warm and one cap bulging but the caps
tested out similarly, eg, VLoss ~1.8%, Cap ~1150 uF and ESR ~ .1?


Your tests were when it was cool?

Yup ...

Closest to the toroid?

Not when they were off the PCB and I was testing them. ;-)

Missing the fan?

They may have been. ;-)

But all the above are why I have already ordered some replacements and
*if* they allow it to function again, may offload some of the load
onto an additional PSU as well (for the 24V heated bed). ;-)

I just was ready to see the one with the bulge show very different
results (even cold) but it didn't?

Cheers, T i m