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I come to you today for a rather special request, but you may be the best people to answer it.

I am a developer and I have an Ikea standing desk (automatic one) in an open space.

I have a big static electricity problem: When I get up from my chair, it blanks some screens, sometimes those of my desk, sometimes those of my colleagues. It blinks and show a black screen for some seconds.

Here is a video that explains the problem : https://www.youtube.com/watch?v=r-V_Z3bD_PA&feature=youtu.be

Details on how to reproduce this problem:

  • Be charged with static electricity.
  • Touch or not touch the desk or anything else (it doesn't change anything)
  • Simply get up from your chair, and the screens turn off.

Nothing is connected to me or the chair. It's really weird.

  • 10
    Try wearing different pants. I am serious... – Eugene Sh. Feb 13 '19 at 15:50
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    Oh, you mean computer monitors go blank due to a static discharge when you get up. Sorry for the confusion. I saw a recent video by Dave Jones on this very topic. – JYelton Feb 13 '19 at 15:50
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    What is the chair made of and what are your pants made of? Eugene isn't joking about wearing different pants; that seriously could help. – Hearth Feb 13 '19 at 15:52
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    @EugeneSh. No pants also works, and might be more fun. – pipe Feb 13 '19 at 15:56
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    Then you might want to ground your chair/desk. Just pull a wire from it and connect it to your desktop case or some other grounded surface. But better do it through some resistance to avoid shock if you have some bad equipment around... – Eugene Sh. Feb 13 '19 at 15:56

11 Answers 11

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Static discharge can range from an annoying inconvenience such as feeling a mild shock touching a metal surface to a costly problem such as destroying sensitive components or equipment.

Mitigating static buildup is a tedious and sometimes complicated process. All of the following and more can contribute to excess static:

  • Dry air (lack of humidity)
  • Fabrics and materials (your chair, trousers, shoe soles, carpeting, desk surface)
  • Friction from moving parts (if you work in a factory, static can arise from all sorts of moving items including conveyor belts, piping, powder dispensing, plastic film, etc.)
  • Lack of grounded structures/wiring/connections
  • And more...

Mitigation steps:

  • Test different materials for trousers and shoes (try leather soled shoes). Chair and carpet are also factors but likely more inconvenient and costly to change.
  • Purchase an ESD mat for your desk. They dissipate electrostatic charge and you could make it a habit to be in contact with it as you get up.
  • Increase the humidity of your workspace. 35-40% RH should be sufficient, but this may not be possible due to your location, employer, etc.
  • Touch a metal/conductive portion of your desk (such as the frame under the top surface) as you get up. (If this doesn't help, your desk is isolated and could be grounded with a connection from the metal frame to ground -- it should already be grounded if it is a mechanized standing desk).
  • There are various anti-static products such as clothes dryer sheets, water misters, etc. which may work but be inconvenient to use, refill and maintain.
  • An employer of mine required everyone to wear ESD shoes or heel straps when entering a particular production area. You could potentially try inexpensive heel straps, but the effectiveness will depend on the type of flooring and construction of your work area.

The monitors you are using may be unusually sensitive to static discharge, potentially due to poor cable shielding, improper or insufficient grounding, or component/circuit/PCB that isn't chosen or designed well to reject interference from such discharges (read: cheap monitors). You could try changing signal and power cables to ones that include shielding or ferrite cores to help reduce their exposure to ESD, but in my experience it has rarely helped as much as reducing static directly.

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  • Thanks a lot for your complete answer @JYelton ! I just tried to put a metal wire metals parts of my chair, and touch it before standing up : It works. Probably not the most comfortable way to solve the problem. I'll try in few days your other solutions. Again, thanks a lot to you and others that helped so quickly :) – André DS Feb 13 '19 at 16:18
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    Keeping static from building up with conductive paths to ground is best, but you might want (as Eugene Sh mentioned in a comment) to include some resistance in case you are ever working with live power at your desk. 1MΩ is typical for ESD mat connections to ground. Cheers! – JYelton Feb 13 '19 at 16:27
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You might want to check (or rather have an electrician) check the grounding situation of your AC mains outlet and see if it is really connected to ground. The computer and monitor should be connected to the same ground. The monitor itself should have a UL mark or similar ETL (like TUV ect) to make sure it's been tested against ESD. Make sure the monitor cable is plugged in correctly and the shield of the monitor cable is making contact with the chassis of montor and computer

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  • I will contact the person in charge of the premises so that he can do the needed actions, thank you for your answer – André DS Feb 13 '19 at 16:57
  • I have a cheap plugin tester for power sockets - works well to show if there's a wiring fault. It lives in my PC toolbox, and have proved useful many times. – Criggie Feb 13 '19 at 19:07
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Spray the floor/chair mat and the chair itself with Cling Free or similar anti-static product for clothing. You need to repeat the application every week or couple of weeks but it works really well for controlling static charge without any downsides other than the perfume smell (which dissipates).

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3

Most problems with electrostatic discharge is the shoes. Try other shoes.

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    And again, "no shoes" is one option that I use. – Dave Tweed Feb 13 '19 at 23:47
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I realize this is an answered question but came across another possible solution.

Apparently, the gas-lift mechanism found in office chairs can produce an EMI spike when someone sits / stands.

Enough people have had this issue that it is mentioned in DisplayLink's knowledge base (with a link to an article from 1993 describing the issue).

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1

What kind of chair do you sit on? I had this same exact problem happen to me when it started to get to the winter months which I assume was due to lack of moisture in the air. I solved it by switching chairs. The previous chair had a cloth material and my new chair has some kind of leathery material. I heard about some of the other solutions mentioned in this thread and the simplest for me was to just change chairs. I haven't been shocked one time since.

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Similar to the suggestion to use fabric softener spray, you can use a fabric softener laundry additive. This has the advantage of being available without fragrance. I believe it is also less expensive than aerosol spray. Add a mixture of water and fabric softener to a spray bottle, and then spritz carpet and furniture fabric with it every few days.

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Some monitors use single-ended capsense inputs versus tactile switches to save on manufacturing costs.

If this is the case you can try shielding the buttons with a piece of aluminum foil that is electrically connected to the chassis of the monitor.

Large E-Field transients may false trigger a single-ended capsense input.

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If you're still having this problem, do what I do, particularly in the winter. Lightly spray some Static Guard all over the front and back of your chair. I do this whenever I start getting shocks when I get up and touch something. Once I spray the chair, no more shocks for weeks. I hope this stops your monitor from blanking out.

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I have had the same problem with two external monitors at my desk for the last year. Finally today I was able to duplicate the symptom, which allowed for lots of testing. Every test resulted in my monitors going off. I knew it was a static problem, but I never had this problem with the same monitors on my previous computer. I eventually thought it might have something to do my my chair mat (on carpet). I removed the chair mat and it stopped. Now I need to find a good anti-static chair mat so I don't destroy the carpet in my office.

So, for me, replacing the static mat solves the problem. There are also chairs with conductive wheels and fabric that you might want to consider.

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  • Are you sure replacing the static mat solves the problem? Or just not using one at all is your solution confirmed, thus far? – Pimp Juice IT Dec 12 '19 at 23:58
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my office chair wheel base is is metal and pc's sub-woofer placement was my issue. It was only less than 12 inches apart and served as my foot rest too. Move sub-woofer further away and issue resolved.

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