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I need to open up my laptop for some cleaning and repasting.

I watched some tutorials online on how to use an anti-static wrist strap and they all tell me to

  1. Have an extra desktop computer.
  2. Turn the desktop computer off, but keep it plugged in.
  3. Clip the strap to the desktop computer’s case.

But I don’t have a desktop computer. Can I connect the strap to some suitable household object? Can I use stainless steel kitchen utensils and such?

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    \$\begingroup\$ Desktop is easier since you can just ground yourself to the chassis. Laptops are plastic. Can you sacrifice a USB plug, connect your strap to the chassis of said USB and plug it into your laptop while you perform the repair/autopsy? A conductive mat on your desk is recommended. \$\endgroup\$
    – winny
    Jun 24, 2022 at 11:58
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    \$\begingroup\$ Simply keep one finger on any metal ground on case or board \$\endgroup\$ Jun 24, 2022 at 12:08
  • \$\begingroup\$ Keeping a desktop plugged in while working on it is bad advice. There is a 5V supply that stays on and powers up various items on the mobo when the computer is "off". As for anti-static precautions, take your shoes off and go barefoot. This is usually enough to drain static charge from your body to earth as long as your feet are touching the floor. \$\endgroup\$
    – qrk
    Jun 24, 2022 at 20:17
  • \$\begingroup\$ @qrk okay, I’ve noted that. Thank you very much! \$\endgroup\$
    – Egoless
    Jun 27, 2022 at 14:04
  • \$\begingroup\$ @TonyStewartEE75 but if that metal is not grounded wouldn’t the static just stay between me and the metal and if I touch computer parts they’re still gonna get shocked \$\endgroup\$
    – Egoless
    Jun 27, 2022 at 14:08

2 Answers 2

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What you need to avoid happening is your body discharging static electricity to the circuit board you are going to work on unless, that discharge is directly to the circuit board's ground or 0 volts. If you discharge static to the circuit board ground that action can be regarded (in normal circumstances) as being fairly safe for components on the circuit board.

Ideally though, you need to equalize any static potential on your body with respect to the target circuit gradually to avoid creating a spark or a high energy impulse. This is why 1 MΩ resistors are used in the wrist strap when it is normally connected to the anti-static mat on which your target circuit board sits on.

But, by the sound of it, you don't have the luxury of a mat so you have to "tread" carefully and connect your earth strap (through a 1 MΩ resistor ideally) to a port on your laptop that could be construed as being suitable. By "suitable" I mean closely bonded with the 0 volts on your laptop circuit board.

Connecting your earth strap to ground (or earth) on a wall socket in your house is missing the point unless, your laptop circuit board's 0 volts is also connected to that earthing point.

So, make an equipotential bond via your wrist strap to the laptop circuit board and be very careful in how you choose the electrical point to make that connection. Any other equipment or components you might use should also be carefully bonded to that common point and, this is why ant-static mats are used; they keep everything on your workbench at the same potential.

If you don't have an antistatic mat be very careful and think twice about collecting the equipment and components around you that you need. There's nothing much you can do about signal generators other than electrically bond them to the common point but, components can be kept in your pockets until needed and don't let go of them until they are touching the circuit board.

Better still, get a mat and do it properly.

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  • \$\begingroup\$ Thanks. I’ll get a mat. What do i connect the mat to though? \$\endgroup\$
    – Egoless
    Jun 24, 2022 at 14:31
  • \$\begingroup\$ Normally it connects to earth via a special plug that also allows you to connect your wrist strap to. \$\endgroup\$
    – Andy aka
    Jun 24, 2022 at 14:34
  • \$\begingroup\$ Any alternatives? How is the anti-static plug wired inside, am I gonna be connected to the earth wire on the socket? I looked it up and it seems to be dangerous \$\endgroup\$
    – Egoless
    Jun 24, 2022 at 14:36
  • \$\begingroup\$ There is a 1 million ohm resistor either inside the lead of the wrist-strap or inside the plug. No risk of damage especially as it connects to earth. \$\endgroup\$
    – Andy aka
    Jun 24, 2022 at 14:43
  • \$\begingroup\$ @Egoless Please read these two paragraphs on wikipedia \$\endgroup\$
    – Andy aka
    Jun 24, 2022 at 14:46
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There are commercially available adapters that plug into 3 prong grounded outlets, and have a banana jack for attaching a wrist strap or grounding mat. For example HPFIX Grounded Outlet Plug, Anti-Static Wrist Strap (Adjustable up to Size XL) and Grounding Cord, Earth Connection | ESD Safe for Computer, PC Building Eelectronics - - Amazon.com"

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  • \$\begingroup\$ How is this helpful if you don't have a grounded electrical system in your workspace? \$\endgroup\$
    – Jacob Lee
    Dec 19, 2022 at 0:26
  • \$\begingroup\$ @JacobLee If you don't have grounded electrical outlets, then obviously, you can't use this device for grounding. \$\endgroup\$ Dec 19, 2022 at 0:59

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