Also called an antistatic strap, antistatic wrist strap, an antistatic band, or an ESD wrist strap, a wrist strap wraps around your wrist with a conductive cord attached to the computer. The wrist strap keeps the user grounded, which helps prevent electrostatic damage to a computer or any other electrostatic-sensitive device. The picture shows a wrist strap with a detachable strap around a wrist.
Why should I wear a wrist strap?
Suppose you're going to open a computer case to attempt a replacement or repair of parts inside the computer. In that case, you need to use static grounding protection to protect the computer, motherboard, and other hardware. People can transfer static electricity to the electronic parts of the computer, potentially damaging them. Wearing an ESD (electrostatic discharge) wrist strap grounds the user, preventing static build-up and protecting the internal parts of the computer.
Some antistatic wristbands have a battery in the wristband to create a ground. It does not connect to the computer or an antistatic mat, as the battery power provides the same grounding as a wired wrist strap.
How to use a wrist strap
Place your wrist in the strap and attach the other end (often using the alligator clip) to a non-painted metal portion of the computer case, antistatic mat, or antistatic workbench. While working on the computer or another electrostatic-sensitive device, the wrist strap should remain on your wrist.
What to do if you don't have a wrist strap
Although using a wrist strap is best practice, it is not the only way to ground yourself. If you don't have a wrist strap, but you need to open your desktop computer case to upgrade or repair its components, you can ground yourself by touching the metal of the chassis. To do so, follow these steps.
- Make sure the computer is shut down and powered off.
- On the back of the computer case, where the AC (alternating current) power cord connects to your computer's power supply, locate the power supply's on/off switch. Make sure it is switched OFF (indicated by an open circle, ◯).
The computer should always be completely powered off, and the power supply switched OFF in the back of the computer before the AC power cord is disconnected.
- Unplug the AC power cord at the wall outlet or power strip.
- Then, disconnect the AC power cord from the power supply on the back of the computer.
- Disconnect all other cords and cables from the computer, such as audio and video cables, wired keyboard and mouse, etc.
- Position the computer case on a clean desk, table, or workbench near a grounding power outlet with a 3-prong receptacle (three holes in the outlet). If possible, work in an area where the floor has no rugs or carpet because they can generate static electricity when you walk on them.
- Open the case. (Every case is different. Refer to your owner's manual for specific instructions on how to open the case.)
- Before touching any internal components of your computer, connect the AC power cord to the power supply in back of the computer. Then, plug the cord into the 3-prong outlet. Do not switch the power supply ON. Leave the power supply switched OFF.
- Now, you can ground yourself by touching the non-painted metal of your computer case. Any electrostatic charge is transferred to ground through the power cable, to the grounding outlet. No electricity is flowing into the computer, but static is safely discharged to ground.
- As you work inside your computer, every time you need to touch a component, touch the metal chassis first. You only need to touch it for a moment to discharge any static electricity.
- When you are done working in the computer, close the case.
- Before powering on the computer, reconnect all cables and the power cord, and plug the power cord into a 3-prong grounding outlet.