Wall Wart died?

[Jeffl]

I have a 7.2v 2900mah power supply for my BetaBrite that puked last night.  For the past few years I have powered it from a LOR AC controller.  This year I tried a DC/AC SSR and it died after about 6 hours of use.  I’m trying to understand if it was from heat as it was enclosed in a wood box or if the power from the SSR was bad.

I’m curios if I should try a new supply with the same setup or switch is back to being powered  from a Lynx Express?

[Dennis Cherry]

Saw you post heading and mis-read it first time.

I thought the heading was WAL MART Died,

[Steve Gase]

+1 

[Jeffl]

Too funny. I updated the title.  I also switched the BetaBrite back to an LE (much simpler).  It's a huge linear power supply and I think the old one just hit its useful life.  If this one goes there will be no more sign.  And that will be a simple fix to the problem.

[rm357]

Be sure to set the LE light curve for that channel to Strobe. Power supplies should not be dimmed - the dimming puts out a lot of electrical noise that the power supply is not going to do well with...

[Jeffl]

I'll do that. 

I have read different post about this but I would like to see a scope view of the LE with and without the strobe setting set.  I'd also like to see the DC/AC SSR but I don't have a scope.

I looked at the power supply and it comprised of a huge winding, large cap, fuse and I think 4 diodes.  It's a very simple design and it's hard to understand why it would care what the  input power looks like.

[rm357]

Here are a couple of write ups on dimming methods. All of ours is of the phase forward type where we rely on the triac's normal behavior to turn off when the voltage across the device reaches zero (at the zero crossings).

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That last web site is a little dated and incomplete when it starts talking about using a pic for dimming, but it gives a good idea of how it works