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let us say that I have built a metal cabinet in which I will be painting small objects. I am looking to eliminate any static electricity that could possibly build on the object to be painted or on the cabinet. The object will rest on a metal turntable which will rest on the metal cabinet, which I am hoping to be able to connect to ground.

Can I connect the metal frame of the cabinet to the ground (third prong) of a nearby outlet to ground the entire cabinet and part and possibly eliminate any static electricity?

By "Can I," I am hoping to hear responses regarding the efficacy of this method of static elimination and regarding the safety and possibly electrocution hazards of this method.

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  • \$\begingroup\$ That should work very well, IF the third prong is grounded. I've found wiring that someone had skipped that step. \$\endgroup\$ Commented Mar 4, 2013 at 18:42

2 Answers 2

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You certainly can. In fact, you can buy a special plug just for this purpose:

ESD Earthing plug

It's called a static earthing plug, and is readily available, for example from PC Valet. The plug contains 1 megaohm resistors between the metal buttons and earth to protect against massive discharge currents.

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    \$\begingroup\$ I'll be calling it a ScaryPlug. \$\endgroup\$
    – sharptooth
    Commented Mar 5, 2013 at 14:45
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In general you don't want to tie into anything with low impedance, simply because if there is a circuit fault you can become part of the circuit. That's why 1 Mohm resistors are tied to ESD straps. The key here is dissipation not necessarily instantaneous equalization.

So that is the safety side of things.

But there isn't one general super ground available through out every where, what is important for your use is that things are brought to a equipotential - which just means they are at the same voltage. With no voltage difference, there can not be a discharge or in your case electric fields to disturb painting.

So as long as every this electrically connected and you are too and the action of painting doesn't carry charge to the object (i.e. paint gun is connected too) you shouldn't need to ground the whole apparatus to the safety.

But if you do don't forget the resistor!

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    \$\begingroup\$ Little known fact: Those that sell wireless ESD still keep that 1MOhm resistor. One of those things that keeps me entertained. \$\endgroup\$
    – Kortuk
    Commented Mar 5, 2013 at 14:40
  • \$\begingroup\$ Little known fact: A special resistive element derived from snake oil is used in those wrist straps. \$\endgroup\$
    – MIL-SPEC
    Commented Jan 24, 2019 at 13:11

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