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Posted By: SvenNYC How dangerous is this? - 11/14/03 06:11 PM
I've got this wrist-grounding strap (a conductive strip of material with a wire and an alligator clip attached) that I use for grounding myself when I'm working on some solid-state stuff on my workbench (like replacing a card on a computer or diddling with an electronic clock radio).

Anyway....since I have a grounded socket strip on my workbench, how safe would it be to attach the wire of my grounding strap the the ground pin of an old male plug and then stick that sucker into the socket? Assume socket is wired correctly I'm assuming no problem....but still.

Usually I just clamp the thing to the metal casing of the power strip...but clip pops off sometimes....
Posted By: NJwirenut Re: How dangerous is this? - 11/14/03 06:39 PM
That's what I do with mine, with no problems. And I have seen grounding straps (3M, IIRC) provided with a plug intended for this purpose. The plug had 2 plastic blades and a metal ground pin. I would be a bit leary about using a setup like that out in the field, where the wiring/grounding integrity of the outlets is unknown, though.

For safety, a wrist strap MUST incorporate a high value of resistance (usually 1 megohm) in series with it, so you aren't making a direct connection to earth ground anyway. Just enough of a path to drain away static charges.

[This message has been edited by NJwirenut (edited 11-14-2003).]
Posted By: Scott35 Re: How dangerous is this? - 11/14/03 11:03 PM
Like NJWirenut said, most Grounding Wrist Straps for draining / eliminating ESD have a 1 Megaohm Resistor in series, so the user doesn't become a conductor.
(not a train conductor! [Linked Image]...hee hee hee)

Just make sure yours has a high Resistance too!

Scott35
Posted By: SvenNYC Re: How dangerous is this? - 11/14/03 11:11 PM
Thanks guys!!

Yes, this little strap does have the resistor spliced in series with the strap and the wire.

I don't plan on using this anywhere but my own bench. That way I KNOW what I'm plugging it into. [Linked Image]
Posted By: pauluk Re: How dangerous is this? - 11/15/03 06:30 PM
I use of on those when working on MOS devices too. As the others have said, the high value resistance in series is an essential guard to your safety if you did ever accidentally touch an energized part with your other hand.

I have a regular banana plug on mine which will fit the grounding posts on many items of test equipment. It fits just nice in the ground hole of the NEMA 120V receptacles on a power strip too.
Posted By: Trumpy Re: How dangerous is this? - 11/16/03 04:03 AM
My part of the workshop at work has an ESD safety area in it, with a big grounded safety mat, strap and multiple bonding points on it as well as an ESD safe Soldering Station.
You just can't be too careful with Electronic Equipment.
I've seen really expensive controllers ruined by idiots that don't take the simple precaution of wearing a static strap. [Linked Image]
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