Ground tip

[mojo1340]

Here's a simple, easy-to-make gadget that keeps your machine grounded but unpowered. I use it a lot in conjunction with a wrist strap to avoid ESD issues when working in a case. Thought someone may be interested.



It's just a piese of solid copper insulated wire connected to the ground only of a male and female plug set. Just put in between the power cable and the outlet or cord.

Hope this is the right section

[Google]

[fussnfeathers]

Uh.........um...........bad idea? You really really don't want to use an earth ground, it doesn't remove static, nor does it ground anything on the mobo or case............

Brief definition of your "ground pin"........in a nutshell, the ground pin still carries electrical power. In an electrical circuit, both "positive" wires carry power, and the ground pin returns power to the earth. Hence the AC power designation. Alternating current will run down either wire, with the most optimal pin carrying the most power.

In short, you're not only negating any benefit you're getting from your static strap, but you're also connecting your machine to a very serious potential problem. Without the two positive connections, you're opening yourself up to component damage from electricty backflow (ground loop), and yourself to electrical shock.

Also consider that your cable TV line is also hooked to that ground line. You're not removing any EFI at all, if anything, you're ADDING RFI that there's no positive connection to dissipate. The ground pin on your electrical outlet is the primary source of EFI in your house. Case in point, ground loop "hum" in a sound system. Ever heard a low-pitched hum from your subwoofer? That's 60 cycle power noise, and it comes from the ground pin on your equipment. EFI. You want to get rid of it? Unground the equipment.

#1 rule for working on computers..........Disconnect ALL POWER LEADS, do NOT leave your computer hooked up to even just the ground pin. Doing so can result in electrical shock, and will introduce EFI interference without the protection of a complete electrical circuit.

Disconnect that baby, and don't use it again. It's a very very bad idea.
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[fussnfeathers]

Also of note.......using a grounding strap releases ESD into the metal of the case, which is not electrically connected to any piece of your hardware. The ground pin on the PSU will not remove any ESD from you to the earth. However, if you touch a card, while grounded to the case, you're simutaneously grounding yourself to the electrical ground, which WILL introduce an electrical charge into the piece of hardware you're removing.
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[mojo1340]

Well, I'm not an electrician, so I'll defer to you on this. Didn't mean to post any bad info . Feel free to remove.

Thanks, FnF!

[2old2care]

An ESD strap DOES NOT electrically tie you to anything...the "wire" in it is high resistance (carbon kinda like a spark plug) and resides between 1 million and 10 million ohms....SOOOO...if your case is grounded, and you handle a card with a strap on where's the potential?
And....I wouldn't get a within a mile of a distribution system that is capable of having static level (damaging to component) voltages on the earth ground.
Dude....don't take a bath in that house.
Yes...the ground is full of noise....but not potential.

The good arguement to NOT do this is, standard safety practices of safe work.
IF you are working on your case while it is grounded (and since it is a conductor) You MUST consider it live (or powered) because you can potentially get into a return circuit.
SOOO...use a good ground strap...then you dissapate the charge (capacitive) through a high resistance and longer time...safely. And if you tie your case to ground...consider it live.
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[Silicon Skum]

The correct way to use a grounding strap is to have it connected to the case of the computer, therby you are at the same electrical potential as the components you are removing. If you have a work bench with an electrically conductive mat / work top, anything in contact ( components, entire computer etc) will be at the same electrical potential, so no risk of a electrostatic discharge.

I never use grounding straps, just keeping one hand on the computer case does the same job. As long as you are not in a room with nylon carpets and low humidity, you really shouldn't have too much problem with ESD.

Static electricity is just plain old DC electricity at very high voltage and low current. A typical charge a human body can gain after dragging their feet accross a nylon carpet is about 2Kv ( current will be in the low Micro Amp (uA) range, mA is miliAmps). this will be enough to jump a spark about an inch or so.

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[fussnfeathers]

I'm just posting electrical safety standards......I build power taps for my PA systems, so I've learned a bit of electrician skills over time. I use one for my computer (cleanest power in the house). Plugs into a 220 outlet, connects to the input voltage wires on the breaker box, or plugs directly into an empty breaker on the box. Basically, I bypass my house power and go directly to the 220v incoming line. No ground loops in my house.

Anyway, yes, you can get a charge off the ground pin. Granted, it's a small charge, but it's certainly enough to zap your video card, if you're like me, and grab the case for a bit of support while you pull the card out. If your finger slips and hits and IC, you've just grounded that chip to the earth ground running to your electrical outlet. Not a smart thing to do, really.
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[2old2care]

I think we are all on the same path here....I am saying you don't ground the case because you might find yourself in series to current flow Life safety no-no.
Also....note the ground strap stuff....IT IS NOT A GROUND....NEVER GROUND YOURSELF WHEN WORKING AROUND ELECTRICITY....a ground strap is several million ohms to ground...not ground.
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Liquid-Cooled Q9450 and an EeePC
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