Surge suppressor design

S

starhawk

[H]F Junkie
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Oct 4, 2004
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So Mom's ten year old UPS finally died... death by drink, to be specific -- it had a splash of orange Crystal Light and that was too much for it; it couldn't tell that it was plugged in anymore. A look at the PCB inside revealed some significant damage. At least the battery didn't short!

I'd like to reuse what's left for a surge strip. That would be the chassis, some wires, the power cable, and a 15a 250v pushbutton-type circuit breaker.

I found what looks --to my uneducated eyes-- to be a good design for a surge suppressor circuit, here --> http://diagramplus.blogspot.com/2013/04/simple-lighting-surge-protector-circuit.html
Well, OK, to be fair, that site stole that article from somewhere else, but if the article can be trusted, the design is sound.

Two potential problems, though --
(1) I don't really have access, financially speaking, to a custom PCB house. Even if I did, I know literally nothing of PCB design. This project basically has to be done on Radio Shack perfboard, and I'm not sure how well that will handle the current involved. (Actually, I think I know and I hope I'm wrong.) I'm definitely too clumsy for deadbug style put-togethers as well. Is there a way I could make the perfboard work (I tend towards point-to-point wiring, but I can learn!) or are there alternatives that will work?
(2) Slightly more critically, the circuit in the article is for a 220/240v supply. I need it to be for a 110/120v supply. How should I alter the circuit to compensate for that?
 
While I'm all for DIY'ing your own projects, building a surge protector is something I'd stay away from primarily due to the insurance liabilities. If a fire happens and it happened due to a spark from your DIY surge protector, that's cause for insurance denial.
 
I'm going to be an idiot and press ahead with this.

...would that be mitigated if I lifted a properly rated suppressor circuit out of another device (gently used at most, and I'd try to get new) and stuck it in a different housing? There would be some wire-to-wire-only soldering involved...
 
If the entire device as a unit isn't UL certified or equivalent, you're opening up yourself to liability. Are you looking for an electronics project? There's many kinds of projects out there that don't involve line voltages...
 
I'm looking for a good way to reuse the non-destroyed guts of the UPS. That would be the cable, housing, and busbars for the outlets, along with the previously mentioned circuit breaker.

I can go for "or equivalent" -- my soldering skills should be (just barely) up to par for that. I've seen some scary shit slapped together that's UL approved.
 
By equivalent I meant if you were outside the US, as other countries have different standards. To me, it's not worth risking a possible insurance payout to save the $20 or so that a surge protector costs. Good luck and have fun with your project.
 
Well, I'd like to do *something* with these parts... do you have an alternative suggestion?
 
If you're building something on perfboard and want to handle larger currents, just beef up the traces with solder. You'll see similar techniques used in computer PSUs.
 
Project cancelled, for now at least -- more because of cost than anything else.
 
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