Static...

[Nathan]

I'm going to be setting up static floor mats where I'm working. I need some info on how to set up a ground strap properly so more than one person can be working on computers on the workbench at the same time. They want it done right. So any info anyone can provide will be helpful. Also I would like info on a portable mat that I see some techs have. Eventually I will ask the computer repair service that comes in and does the warranty work where they got their's. I would prefer not to wait that long if possible.

Thanks for any help.

[welsh wizard]

If you want a cheap way, then A trader I know who also does some repair work made up a cheap bench as follows.
1 old work bench/table
2 piece of Alum. thin stuff
3 He placed ally on table then tacked it.
4 screwed through alloy and connected with wire I think he used some old house wire loom he had lieing around.
5 Ran wire out of workshop to a piece of copper tube he had driven into ground.( he soldered wire to it)
6 along the back of the bench he screwed in a number of philips screws which he connected some Motorcar loom wires, he then used some old watches with metal straps as earthing strap for wrist.

He reckons it works great,

BUT BEWARE DO NOT WORK ON POWER SUPPLY OR MONITORS WITH THIS SETUP.

Apart from my first impression of his bench being rather Heath Robinson, I must admit it works fine /forum/smile.gif
WW

[alpha]

Don't put a motherboard on it either or it could short it's battery

[Axel]

If you are working on PC's you should be aware that less than 1/10th of 1 percent of damaged components are due to static discharge.

On other equipment like mainframe boards and Telecom equipment, it's only slightly higher.

Most experienced techs don't even wear a grounding strap anymore - they just make a point to touch something metal before starting to play with the components to "discharge" themselves.

And Welch's comments about working on a power supply or hot board are more important than the one out of a 1000 components you might save with a grounding strap.

[pickel]

Nathan: Check out this site and see my comments about being grounded http://www.sysopt.com/forum/smile.gif
http://Sysopt/forum/Forum2/HTML/003099.html

Nathan: Goes right to the site on my computer
Try a different Browser, if you have one http://www.sysopt.com/forum/smile.gif

[This message has been edited by pickel (edited 12-02-1999).]

[Nathan]

I'm getting an error message stating it can't connect to the server pickel.

[Nathan G]

umm.. http://www.sysopt.com/forum/Forum1/HTML/002222.html http://www.sysopt.com/forum/wink.gif..
Axel: where are you getting you ESD stats from? look here at first table! http://www.borg.com/~eosesd/cebasics.html

BTW you will note that good work bench Static mat have a "buried conductive layer" (the top working surface is non-conductive)eliminating the possibility of a sudden battery/cap discharge. Exposed, conductive working surfaces such as alloy is a bad idea for several reasons. It sets up favorable conditions for ESD events and is a possible safty hazzard!
Note: professional grounding straps have a large value internal resistor (1M ohm range ??) in series with the clip. This is very important to keep large amount of current from flowing thru you if you were unlucky enough find a charge somewhere in device you are working on. remember: current will take path of least resistance, and you dont want to be part of that path!!


WW - "Heath Robinson" ROFLMAO hehehehe http://www.sysopt.com/forum/smile.gif love that terminology!

sorry bout all the edits http://www.sysopt.com/forum/redface.gif

[This message has been edited by Nathan G (edited 12-03-1999).]

[Nathan]

Nathan G., fantastic. Just what I was looking for. I owe you one.

[Nathan G]

I wish to put this thread ,with this link, up top one more time for those of you that think ESD safty is not a real concern.

please read this: http://www.borg.com/~eosesd/cebasics.html

[welsh wizard]

Nice one Nathan G,
goes to prove the point perfectly http://www.sysopt.com/forum/smile.gif
WW

[Axel]

Looked at the table Nathan - Good Grief - the bone heads blowing 70% of their equipment with ESD must skid across the floor in silk undies before working on their systems! - Can't say I have a lot of pitty there - I'm in the telecom industry - we're used to touching a ground before messing with our circuit cards and I've never seen damage like they indicate in the table you've got referenced.
Also - notice the source - their industry expert is someone in the business of selling anti-static devices - please! I'd say the source had a slanted motive. If anything, I might be tempted to go with you on possibly 8% loss from production facility through useful life - whatever that may be for various different electrical components in different environments. That covers a WHOLE lot of ground with a WIDE range of users., but the 33% mark - I've got serious doubts. - Haven't seen it myself - perhaps I've been lucky.

[Nathan]

I'm impressed. I couldn't have said it better myself Nathan G. (nice first name there hehe). I can understand people not understanding this.

I'm going to propose to have anti-static floor mats under the table and chairs. And have the portable pads/straps for in the field work. It's not going to be cheap, but toasting a motherboard and CPU isn't either.

[pickel]

The knowledge base keeps expanding Thanks for an excellent site http://www.sysopt.com/forum/smile.gif

pickel

[Nathan G]

I personally do not feel a elaborate bench/floor/mat setup is needed.A work mat is really only needed if you work on the component level (ie swapping EEPROMS/RTC chips hehe) or in field service where you dont know if your working surface will be conductive or not(and its potential). In that case clip mat to equip under work after unplugging. Just put the board in an ESD baggie before you unclip and the mat is not needed. In order to reduce to the chance of an ESD event, It is not absolutly required to be grounded to earth, (unless you are going for ISO Cert. as a mfg.) as long as you and the equip you are working on are at the same potential (clipped) no ESD events should occur.
BEFORE YOU CLIP ON TO EQUIP Be absolutly 100% certain there is no source of power!! POWER CORD,Monitor,UPS, yes even phone line (i am paranoid) etc. connected.
We want to keep ya around for awhile! http://www.sysopt.com/forum/wink.gif
A good strap with clip and following procedures mentioned in first link http://www.sysopt.com/forum/Forum1/HTML/002222.html
9.00 bucks per person for a strap w/clip.
http://www.jameco.com/cfm/viewdesc.cfm?part_num=159257
well sorry to babble on. feel like i just kicked a dead dog.hehe Nathan is a good name and the G is short for
GluÊÜtious Sparkticuss http://www.sysopt.com/forum/redface.gif. i must say i disappointed by the lack of jokes/comments in reference to the "nature of my spark" that destroyed my video card.
after all: "The amount of charge created by triboelectric charging is affected by the area of contact, the speed of separation, relative humidity, and other factors." LOL
Happy Holidays all! ..I said it first, shoot me!




[This message has been edited by Nathan G (edited 12-03-1999).]

[Nathan G]

I am certain that the 8% range (or higher) is a heck of a lot closer to reality, than the 1/10 of 1 percent. http://www.sysopt.com/forum/wink.gif
Being in telcom you must know that your equipment is required to pass ESD Testing during Electromagnetic Compliance Certification. Telcom gear also falls under part 68(i think) of FCC regs. The kind of gear i am guessing you are working on is designed to be very rugged against all kind of nasty things like ESD events and Electrical Fast transients etc,etc..). Most equipment that interface with network/phone line must pass these tests.The fact that your Co. has had good "luck" is a testament to your product design team and the fact your gear is held to tighter specs. than most consumer gear. Most consumer equipment in the standard PC today is not nearly as immune to the nasties. Plenty of Co.s have spent big bucks trying to reduce ESD related failures and you suggest this is all unneeded and they would all be fine just touching chassis..umm lets just "agree to disagree" on this!
Let me tell what happened when i zorched a video card with ESD. I Removed unpluged monitor,cover,then touched chassis, removed card. while card was in hand i stood up from from the chair and bumped case with card and "pow" blue arc. Dead video card! Note: no ground strap on & i didnt unplug unit so chassis was earthed a BIG nono http://www.sysopt.com/forum/redface.gif
The slight movement of my **** on the chair generated enough static to kill the card..[insert joke here http://www.sysopt.com/forum/smile.gif]
Most equipment can take a hit from the outside but when grabbing circuit boards, ICs and internal components, a discharge has a greater chance of doing some damage.




[This message has been edited by Nathan G (edited 12-03-1999).]

[mattheadfat]

i've installed ram and video cards on friends computer where i only touched a metal desk to ground myself and unpluged the power to the computer before opening it up and working on it, is it really that dangerous???

[mattheadfat]

i've installed ram and video cards on friends computer where i only touched a metal desk to ground myself and unpluged the power to the computer before opening it up and working on it, is it really that dangerous???

[Nathan G]

Good point.. 2 different different issues here..
1) for safty of people opererator or maint tech.
2) for equipment being worked on
priority in that order as well

If you unplug and dont use a ESD strap you are mainly risking equipment and not to yourself.

If you replace RAM for friends say 1 or 2 a year... hell chance it if you wish... but i only reccomend a 9.00 dollar solution to greatly reduce that risk ( how much did that RAM cost + shipping you say ...aww too bad http://www.sysopt.com/forum/smile.gif ).
ESD events occur in drier air soo most of us will notice it more occurances in the winter season....
ok i edit a lot :0

[This message has been edited by Nathan G (edited 12-04-1999).]

[Nathan]

You know Nathan, too bad we can't track people who start using a ground strap. I mean ask them if they have any failures after removing used and new devices, motherboards, etc. since using it.

A ten dollar investment can save a lot of money and grief when it comes to computers.