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Is a GFCI outlet a good or bad idea for an electronics workbench?

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I'm setting up an electronics workbench, and I wanted to get some expert advice as to whether I should or should not use GFCI outlets.

I plan on constructing a grounding station that would be wired into the grounding prong of a standard plug, which would be plugged in, of course.  I don't know if a tripped GFCI only cuts off Hot, or if it cuts off everything including Ground.  If it does cut off Ground, than I would imagine that to be a safety issue - since if I'm working on something that's powered by anything other than that outlet (i.e.  batteries, a different outlet, etc...), and a problem comes up, I'm going to need that Ground for safety.

The same holds true for any self-grounding tools like soldering irons, etc...

If GFCI outlets don't cut the Ground when tripped, than that alleviates that concern, but there's still the issue of nuisance tripping - which isn't a big issue for a regular guy just using appliances, but someone working on electronics makes very active use of Grounds, and I would think it would trip often.

So, can someone experienced please chime in and tell me if I'm mistaken in my concerns and should use a GFCI outlet, or if I'm correct and therefore shouldn't?

Thanks!  :)
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I hold an EE and EC License in three States, your idea of using a GFCI is excellent!
Safety is so very important!   :)

Furthermore, down the road consider purchasing an isolation transformer and/or a variac!
However, make sure the Xfmr or Variac has a decent current capability; 20A

Remember, do not get the above confused with a ground wrist strap!
A wrist strap is connected to ground through a coiled retractable cable and 1 megohm resistor.
The latter allows high-voltage charges to leak through but prevents a shock hazard when working with low-voltage parts.
When higher voltages are present, extra resistance (0.75 megohm per 250V) is added in the path to ground to protect the wearer from excessive currents etc...
Excessive HV (RF amplifiers) that use larger voltage/current to excite a tube should refrain from using any wrist strap and/or anti-static smock etc...
The latter will only produce more danger and risk of electrocution.

A lot depends on what you plan to troubleshoot and/or design.

Your one of the few that view safety as a primary caution!

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Thank you both.  Knowing that GFCI doesn't cut Ground alleviates my greatest concern.  I can't imagine that it's that unusual for safety to be a priority when it comes to electronics - I can't see how it *wouldn't* be an obvious concern.  :)

That being said, how often is it likely that the GFCI would give nuisance trips?  In other words, how often, when working with electronics, is it that people need to flow over 5 mA to Ground on purpose?

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The only issue i am aware of concerning a nuisance trip when using a GFCI would be motor control circuit.
Occasionally, a motor/pump circuit can draw a large inrush current that will trip a GFCI.
The latter is one of the main reasons why a GFCI is rarely installed on a refrigerator branch circuit.

Furthermore, you can configure your bench with the availability of GFCI and a conventional receptacle in the event the latter receptacle is necessary.

"I can't imagine that it's that unusual for safety to be a priority when it comes to electronics - I can't see how it *wouldn't* be an obvious concern."

Oddly, an engineer usually doesn't pay much attention to safety since the majority are designing and/or troubleshooting around low voltage.
Where as an electrician has the utmost emphasis on safety since he/she is generally working on a voltage that is deadly.

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  • 13 years later...

I'd like to ask OMNI a question (if he's still alive).  He wrote his answer in 2007 and I'm asking in 2021.  Anyway Omni, you recommend using a GFCI for safety.  Then, you also recommend having a Variac and an isolation transformer.  I understand having a Variac.  When powering up an unknown condition piece of electronics like an old Tektronix oscilloscope it would be best to slowly raise the input voltage slowly in case there was a bad short in the scope.  But I've been reading pros and cons about using an isolation transformer especially if the device under test and the test equipment are all plugged in to the same isolation transformer.  I've got the idea that the only time to use an isolation transformer is when working on a device (like an old ham radio or TV) that does NOT have a power transformer.  That is, a device with a hot or live chassis as some old time appliances used to have.  And then, I would think, only plug the hot chassis device into the isolation transformer and plug the test equipment into a regular outlet or the GFCI.  Am I correct?  I'm trying to set up my bench so I don't kill myself before the time chosen by the Lord.

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  • 1 year later...

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