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I thinkI fried my GPWiz40MAX - Any tips to protect against ESD?
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Nephasth:

--- Quote from: lilshawn on March 24, 2011, 12:25:27 am ---also...touch something else first... find a nice shiny metal spot, maybe a stove bolt and ground it. install it in the top of the cabinet. and just touch it first.

--- End quote ---

You can ground yourself out on light switch cover screws too.
laggerific:
Thanks for your thoughts...I certainly hope I don't fry any more parts in the CP before I get used to making it a habit to ESD safely elsewhere.  I was worried that it might be the case that the PCB itself isn't capable of taking the shock...I guess I'll just have to hope the other grounding I do can effectively mitigate the issue.  That said...

The monitor is an LED LCD, and it didn't have a green wire (in this case, should I just run a hookup wire to a screw in the monitor arm to the PC PS?).  The CP was built by me and there are no green wires in there, although with your emphasis above regarding grounding what I can, I think I will try to connect the metal joystick poles with green earth wire down to the PC PS.  And the coin door is an over/under by happ, and I don't recall a green wire, but I am planning on running a green wire from there to a screw on the PC PS, as well. 

Ah, and the USB hub that all is connected to is not wall powered, although I'm not sure if a plug would improve whatever resistance the hub has to ESD.


RandyT:

I can repair the unit for you for the cost of the processor and shipping.  No need to buy a whole new board.  Just make sure the PC is grounded next time, and that none of the inputs are in contact with the metal chassis of the joystick, and you should be fine.  You can also jump one of the ground connections to the metal frame of the stick, as this goes directly to the PC's ground.  The GP-Wiz processor fried because the high-voltage discharge didn't have a clear path to ground, having been defeated at the power strip.

RandyT
MonMotha:
Neither the GGG nor the Ultimarc devices include substantial ESD protection on their inputs, presumably for space and cost reasons.  Generally this isn't a problem, as the chips themselves have some built in, and most zaps are minor, but sometimes it can be a problem.  Even with extreme ESD protection, bit zaps could still occasionally cause problems, anyway.  Looks like Randy has offered to repair your board, so that's great.

If your power strip is saying it's not grounded ("Protected" light probably just means that the surge suppressor hasn't been fried - power surges are different issues than static discharge) and you're not using a so-called "cheater plug" to plug it into a 2-prong outlet, you should have a qualified electrician inspect that outlet (and possibly other wiring in your house).  That's a very unsafe situation.

If you are using a "cheater plug", either stop using it, and plug the power strip into a grounded, 3-prong outlet, or connect the little tab on the cheater plug to a real earth ground, which is what you're supposed to do.

And yes, making sure that everything has a clear (and, ideally, "hefty") path to earth ground tends to mitigate the effects of static discharge.  Your PC supply should connect its power common (aka "ground" aka the black DC wire) to earth ground (aka "safety ground" aka the green/yellow striped wire aka the "third prong" on your outlet).  As long as that is indeed a valid earth ground, you should be good since USB will make the rest work for you.  It would also be a good idea to connect all the metal bits that aren't used for other wiring (so everything but switch contacts) to earth ground (a mounting screw on your PC power supply works well) via "beefy" wire (where "beefy" means "as large as practical").  Most commercial arcades do this for ESD and safety reasons.

Things like ESD mats and sprays would be a last resort, but they're an option.

/Yeah, I like parentheses
//EDIT: The NEW JPAC does have some sort of ESD protection on at least some of its inputs, now that I think about it.
laggerific:
Thanks guys...I did end up buying another, but since the original was swiped from a now dormant CP, it would have a home.  I'll reply in email.

Well, I'm going to pick up a ground test unit from Home Depot this weekend, and some brass clamps for some grounding cable on the sticks...I guess for a short hop the 22 gauge hookup wire would be sufficient?

That said, I have 3 prong outlets, but I'm not sure if any are grounded...I'm hoping at least the bathroom and kitchens are.  Will continue to research.

That said...if all I have is the power strip as a floating ground (or would it be the PC?), is it likely that further ESDs would cause issues in my PC, or would they just fry the power strip or is it effectively a crap shoot?  If the latter, I'm surprised I've been lucky so far, beyond this.  Then again, I can't recall a time I zapped something electric so directly.

Where does one find braided ground cable, and is it particularly expensive?
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