SSR on Ebay

Just got 36 25A solid state relays on ebay for $74. Great deal. Merry Christmas to me. :slight_smile: Now what to do with them? :-/

Nice price. Keep in mind to utilize the maximum 25 amp current rating requires quite the heatsink, that's why they have smooth metal backings.

Lefty

Really! During a stress test of my 2000F Degree Kiln, I managed to produce an amazing amount if heat in the SSR while tuning PID parameters. (all within spec... but right to the SSR limit) Yes, I had a large heat sink. It was HOT.

Just got 36 25A solid state relays on ebay for $74. Great deal. Merry Christmas to me. Now what to do with them?

Heh - I'm kinda in the same boat; a couple of weekends ago I went to a local hamfest and bought a large heatsink with 16 25A SSRs mounted on them (each with a varistor across the outputs) in a 4x4 pattern. Got it for $35.00; have no clue what I'll do with them (but I couldn't pass up the deal!)...

;D

DIY nuclear reactor?

To power lasers!

A nuclear reactor to power lasers. I like it!!!! Now where did I put that plutonium?

I would surely like to find some that did NOT have automatic zero-crossing switching.

Well all scr/triac based SSR are going to be zero-crossing switching from on to off state as that is the only way to turn off a triggered and conducting scr. However the the turn-on can be either random or zero based I guess on the design of the triggering circuit of the device. Not sure if it is always clearly stated in many SSR datasheets or not what the turn-on charactristic are of the device. I would assume that lots of high power random switching would generate a lot of harmonic garbage in the local power wiring?

Lefty

The flat metal on SSRs, is it just for heatsinks and is it usually isolated. Got a plug socket to modify :wink:

The flat metal on SSRs, is it just for heatsinks and is it usually isolated.

Yes to both. Use heatsink paste for best results.

But the 0.1% of us wanting to do phase-angle dimming need the kind WITHOUT the zero-crossing circuitry.

Is this what you are looking for?:

http://www.alliedelec.com/search/productdetail.aspx?SKU=6820149

I am interested in making a phase-angle controller for a split-phase motor, so I would like to know more about this.