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ESD question

Vic

#35422

ESD question | 11 July, 2005

Does anyone knows if usage of plastic trash bags inside trash bins can effect static charge accumulation. And is it preferable not to use such bags to minimize charge.

Thank you

Vic

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Rob

#35430

ESD question | 12 July, 2005

Can't be 100% sure now, but Xerox used to be proud that recycled photocopier toner was used in the process of making black plastic bags.

Toner was full of tiny magnetic particles that were attracted to the electrostatic image transfered from the copier drum to the paper, before being fused by a heating element.

So probably not a good start for a static free environment.

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#35438

ESD question | 12 July, 2005

If they don't come within 12 inches of ESD sensitive material, would it matter? Although to be honest it would still make me nervous.

Anytime you see static cling, you have the potential for ESD. (pardon the pun) Also if you see dust or other fine material "dancing" on the surface while moving something around you have a charge built up.

I have seen definite signs of static build up on some garbage bags.

Stephen

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slthomas

#35443

ESD question | 12 July, 2005

Try sliding a standard plastic trash can liner in and out of the can a few times, then crumble up a few styrofoam (polystyrene) packing peanuts and dump the bits in. You'll be lucky if any of the bits even reach the bottom, unless it's an ESD safe receptacle (the liner is still a risk, though) and/or liner. They are available...just google "ESD trash receptacle liner".

Just keep them far enough away from any ESD sensitive devices so that there's no risk of coming within 12" (I'd probably go with 2' for a garbage can anyway) when you remove the liner.

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URL

#35444

ESD question | 12 July, 2005

Use a metal can and it will ground to your ESD flooring or can easily be grounded with a roach clip to bleed any ESD away. Generally, the plastic cans with plastic liners can build a pretty good charge up.

You should really think "recycling" of just about any product if your thinking of changing your garbage program. After WEEE and ROHS get done with their no-lead solder propaganda campaign, there's gonna be a bunch of nosey people in these groups with nothing to do. So it only figures they'll follow a path of logic and hit the next thing they find in the garbage dump. Didja know ingesting large amounts of dirt is bad for you? Time to get rid the Earth of this evil matter! Imagine the anachronisms!

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Rob

#35445

ESD question | 12 July, 2005

That's alright, we'll be too busy laying on the beach to care, due to the "improvement" in the environment thanks to Mr George Kyoto Bush.

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URL

#35467

ESD question | 13 July, 2005

Global warming? Hmmm, seems to me the Earth has been getting� warmer ever since the Ice Age. Seriously, do you believe lead is a major contributor to global warming or just a severe right wing nut?

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Rob

#35475

ESD question | 13 July, 2005

Good question - lead itself isn't anything to do with global warming - it's main issue in europe is leaching into the water supply, as we bury our trash then build on it & store our drinking water in it, as we have a much greater population density than the USA.

If anything, Leadfree will increase emssions due to the higher temperatures required & increase landfill polution in the short term due to all the equipment & components being disposed of before the deadline.

In reality it's a bit of the old looking for a needle in a haystack whilst someone has set it alight. (i.e. focusing everyone's attention on something small whilst something huge is going on in the background)

Yes the Earth goes through periods of warming between ice ages, however not this rapid, and not with this level of population or degree of civilisation to support.

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URL

#35478

ESD question | 13 July, 2005

Good points. I never thought about the higher temps causing the the higher emmesions. I'm glad I'm not in charge of WEEE or ROHS - but then again it scares me to think who is.

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Rob

#35479

ESD question | 13 July, 2005

Don't worry, your pretty safe now - we have a thing called VAT (a 17.5% purchase tax - ironically named Value Added Tax!) that funds the European Union to the tune of $Billions.

They are usually too busy spending this on monumental lunch breaks in Belgian bistro's, congratulating themselves on another piece of crap legislation they've passed to come up with another great masterpiece in the next few years.

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rsmith@z-mar.com

#35575

ESD question | 15 July, 2005

There are ESD safe trashcans and ESD safe trashbags on the market. If anyone has an interest, please send me an e-mail and I will pass along more info.

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#35746

ESD question | 26 July, 2005

Hi all,

We have been trying to improve our current levels of ESD control in our SMT manufacturing area, while carrying out a initial audit I have found that we have two different grounding planes. One for the electrical grounding through mains power and another for all our ESD controls.

According to ANSI/ESD S20.20:1999, there should be one common ground for all. Can any one suggest any potential risks associated with having two different grounding plans.

Cheers.

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rsmith@z-mar.com

#35791

ESD question | 28 July, 2005

It is important that the ESDS device, the operator, and the work surface maintain the same elctrical potential. ESD events take place when objects of different electrical potentil come in contact with each other. When these different charges equalize, things get violent and the PCB typically loses. This is the reason why we are required to maintain one common ground. We ultimately ground the operator and worksurface to this common point ground. Everything is then at the same potential. Your risk is that if you have two different grounds then it is difficult to consistantly maintain the same electrical potential between your ESDS device, the operator, and the worksurface. However, electrical and earth ground could be tied together. Can you verify if this is the case?

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#35851

ESD question | 2 August, 2005

It is difficult to verify our current state. We are building a new factory, I am trying to push to have one common ground.

But some old timers prefer to have the electrical ground seperate to the ESD ground.

I will check if we decide to have it in this format, wether we can tie them together.

Cheers

CF

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#35859

ESD question | 3 August, 2005

We'd guess that you want the ESD ground at the same point as the building ground for personnel safety reasons. Injured employees and OSHA inspector should be enough to convice the old timers [in most plants].

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Diane

#38405

ESD question | 12 December, 2005

Yes to be quite frank and stright foward your trash cans and bags do affect ESD. Esd also tends to jump thereore you do not actually have to touch the parts to create electrial overstress to the parts. As was mentioned in a previous posting there are ESD safe trash cans as well as esd safe liners availible. Go to your favorite search engine and look up ESD trach cans or recpticles. You can actually damage your esd sensitive components with as little as 1 volt of static electricity. I would recommend looking into IPC.org for further ESD information.

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rsmith

#38650

ESD question | 22 December, 2005

Diane, you are "right on". The key to eliminating ESD problems is to make sure that the operator, the work surface, and the ESDS device are at the same electrical potential. Also you must elimanate any static producers from the ESDS area or provide anti-static alternatives such as ESD trash cans, liners, etc.

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