I have the same lead melt pot, and living in Kentucky, I do use it to
cast lead bullets.  Pew pew.

An honest to goodness PID temperature controller would be an
improvement, and it might be a product as some people would like that
upgrade.  An even better upgrade would be a self cleaning anti-dribble
nozzle.

I use a lot of the Fostek SSRs in my own projects (never for
commercial/industrial work) but I know the 40A rating is a joke.  I
always suspected the newer 40A version is the same as the 10A version
that wasn't good for a reliable 10A.  I generally limit the 40A version
to 5A and I watch them carefully on the initial startup to ensure they
work and don't latch in the shorted condition.  Sometimes I'll test them
manually with the load before installing them in my control panel.  The
internal heat sink potting on the ones I've seen is some white spooge
that isn't silicone grease, and it's very haphazardly applied with a lot
of variation from one to the next.  In general, I take US specs at 100%,
Japanese and German ratings at 150-200%, and Chinese specs at 15-20%. 
And the 15,000 mA hour 18650 lithium cells sold on eBay are pulled from
dead laptop battery packs and they were only rated for 2500 mA hours
when new.

Your little tankards are adorable.   :-)





On 12/19/19 2:23 PM, andy pugh wrote:
> I have a bunch of Fotek SSRs, rated 385V / 40A.
>
> Well, that's what it says on the label.
>
> Perhaps I have been hanging around with Americans too long, but I
> recently bought a bullet-casting melter. I wasn't happy with the
> temperature controller, so I modified it with a PID controller and
> SSR.
>
> https://photos.app.goo.gl/mq4NFtVtiSsVHFSk9
>
> (A variant of that 1/32 DIN controller has a built-in 5A SSR, which
> might be an easier modification, but I used the relay / ssr driver
> version: https://www.ebay.co.uk/itm/193179699038 )
>
> I measured the cold resistance of the element at 111ohms, so that's
> nominally 2A, or 3A if we allow for the actual peak mains voltage.
>
> So I figured that the 40A SSR should be fine. Imagine my surprise when
> it failed short-circuit almost immediately.
>
> It was potted up, and when I pulled it apart the actual driver chip
> fell apart, so no way to be sure what the actual rated current was
> now. The last one of these I took apart had a 10A driver, so that is
> what I have been mentally rating them at. Perhaps I was wrong.
> Possibly it's a fake 10A driver in a fake 40A SSR?
>
> If you are wondering why a resident of the UK wants a bullet mould, I
> have been making tiny glass-bottomed peter tankards:
> https://photos.app.goo.gl/RHmiUKG1BtCT5qW16
>


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