Getting zapped (static shock?) from welding table..

admin

...but only when I get up and re-establish contact with table. I got a couple mild ones at first.. but the latest was bright enough to trip my AD helmet lol. Scared the **** out of me. Tingles up the hand and wrist..  (jumped right through my glove hand!) Seems like static build up somehow. I do not have HF on my unit... My welder is a Miller 200 Maxstar with lift arc (STR).  Only friction is me brushing my welds with wire brush and rolling around in my office chair. Table is wood with a 10 gauge top. I've read as many threads about welding table shocks but nothing quite like I'm experiencing. Any suggestions appreciated. My first instinct is to try to ground the table (top) but not sure how that will effect the machine. Me and the metal top must be charged up and then when I step away I "neutralize" and then the table unloads on me? haha Funny but not funny..Thanks.
Reply:Check that you don't have wet gloves, and aren't standing in a puddle. That always gives you a good zap. Also, shouldn't be a problem grounding to the table directly, or the work piece. The closer your ground is to the work, the less likely it will try and jump through your body instead. (Remember, electrical current always follows the path of least resistance, so make that path to the ground as short as you can).Edit: I have had several shocks, usually after bringing in steel plate covered in snow and gotta fit it up right away without letting it dry off... of course after handling it you get wet gloves and it never fails to wake a guy up if you aren't careful! Last edited by Savfil; 12-20-2014 at 07:42 PM.
Reply:what are you wearing? Plastic office chair, wood table, dry winter time environment, is all a recipe for static. I had a similar situation with my Hobart Stickmate last winter. My table is wood, with a metal top. I had a fleece vest under my welding jacket. As soon as I got rid of the fleece, I stopped getting shocked.Miller Multimatic 255
Reply:I get what you are saying about the materials..but the amount of static build-up seems to be in excess of normal non-welding situations. Naturally, I feel like the welding current is "charging" the table top and setting me up for a zap.As a test,  I should sit down and do some non-energized shuffling around and maybe a little wire brushing and see if I get zapped again without actually firing up the welder. I'd be glad to replicate the intense static shock but I'm not too confident ...we'll see!  All dry conditions. Wearing gym shoes, jeans and cotton hoodie...leather tig gloves..old school thin asbestos tile floor over concrete (basement). Are all receptacles properly earth ground just due to their metal conduit? Should I open the receptacle and see if the ground terminal is wired in properly or am I barking up the wrong tree there.. Would running a small copper wire off the table to under one of the legs do anything? Insulated vs non insulated footwear?
Reply:I just read this on a different forum post..."According to ANSI Z49.1, "Safety in Welding, Cutting and Allied Processes," the workpiece or the metal table that the workpiece rests upon must be grounded. We must connect the workpiece or work table to a suitable ground, such as a metal building frame. The ground connection should be independent or separate from the welding circuit connection." Probably fix my problem..I've heard many a posters say this is not necessary..but hmmm.
Reply:There's millions of welding tables that aren't grounded and don't shock people. What's the difference between a table and a large weldment? You don't have to run a separate cable to ground the piece you're welding on.
Reply:I saw a case where a worker could generate large static sparks at will just by shuffling around a little bit in his work chair.  Solved the problem by putting a bleed resistor from the metal rim on the table to ground.  Don't recall the value but something like 500 k or 1 Meg Ohm.  Like one of those static wrist straps for working on a computer."USMCPOP" First-born son: KIA  Iraq 1/26/05Syncrowave 250 w/ Coolmate 3Dialarc 250, Idealarc 250SP-175 +Firepower TIG 160S (gave the TA 161 STL to the son)Lincwelder AC180C (1952)Victor & Smith O/A torchesMiller spot welder
Reply:I don't think that it is static buildup.  Something else is going on, maybe inside the welder, it could be a very hazardous situation.   Disconnect the cables from the welding table.  Are you still getting shocked?   If not, that points to the welder.   I would connect a cheap voltmeter between the table and building ground, and see what you measure.  You could also hook up the volltmeter to the welder ground and see what you measure.  The welding work (welding ground) should be floating relative to building ground.  If not, then there is a serious problem inside your welder.   A slightly different approach would be to hook up the table to building ground via a 10,000 ohm resistor, which would certainly drain away static charges.  If you turn on or plug in the welder and the voltage between the table and building ground changes, that is not good.   Unfortunately, I am betting on a problem with the welder that could potentially electrocute you.   Do you have any friends who are good with electricity?   I would not want to mess with it without a friend there who could unplug the welder and call 911 if something went wrong.Sculptures in copper and other metalshttp://www.fergusonsculpture.comSyncrowave 200 Millermatic 211Readywelder spoolgunHypertherm 600 plasma cutterThermal Arc GMS300 Victor OA torchHomemade Blacksmith propane forge
Reply:Just to be clear is the shock momentary, like when you shuffle your feet on a carpet and touch a filing cabinet, or is it continuous? If it is momentary, then I say it is just ordinary static. Increase the humidity in your work environment, ditch the plastic office chair for a wood chair or stool, and if you want to ground your table or wear a ground strap on your wrist, that's fine too. I don't think you can attribute this to your DC welder. Like I said I had the same issue, and solved it this way. If on the other hand, the shocks are continuous then you may be dealing with stray currents, and you need to look at how everything is grounded, including the main panel in your home.Miller Multimatic 255
Reply:Just add a small random wire from the table top to the floor. Should kill the static build up.
Reply:Why wouldn't you ground the table? I grounded mine to the closest grounded metal electrical box.
Reply:Your welding table is a giant Lyden jar!The wood structure insulates the metal top. Several Coulombs of electrons build up, just looking for a path to ground.Periodically, it is you (OW).Ground your tabletop and the only discharges you will feel are the ones that build up in your own clothing.Don't worry about the ground clamp side of your welder, both sides are isolated from the power grid to prevent sending totally incompatible power into the building wiring.Be wary of The Numbers: Figures don't lie,. but liars can figure.Welders:2008 Lincoln 140 GMAW&FCAW2012 HF 165 'toy' GTAW&SMAW1970's Cobbled together O/A
Reply:I was welding in a hog barn when the pigs started going wild and bouncing off the walls. When I stopped to investigate one was dead and 2 more unconscious. Luckily I was holding the pens with non-slip rubberized gloves and wearing rubber boots so I didn't feel anything. Turned out one of the grounds in my AC buzz box had burned off. I've also had problems in one shed where the building ground has corroded and isn't giving the best ground for high amperage circuits. Found that out by accident when I dragged the ground electrode over a protective angle iron at the door and got sparks. If grounding your table top doesn't solve the problems, I think you need to investigate further.250 amp Miller DialArc AC/DC StickF-225 amp Forney AC Stick230 amp Sears AC StickLincoln 180C MIGVictor Medalist 350 O/ACut 50 PlasmaLes
Reply:Originally Posted by rafergusonI don't think that it is static buildup.  Something else is going on, maybe inside the welder, it could be a very hazardous situation.
Reply:If it's jumping through dry gloves, the voltage has to be fairly high.  I'd guess static is at least involved.Once the static starts the arc, the welder may be providing additional current.  That'll increase the hurt, and provide the dangerous part.You can buy a spray that cuts down on static electricity.  It's used in labs that handle sensitive electrical components.  Spray it on, let it dry, and it leaves a thin coating of conductive material.Dynasty200DX w/coolmate1MM210MM VintageESAB miniarc161ltsLincoln AC225Victor O/A, Smith AW1ACutmaster 81IR 2475N7.5FPRage3Jancy USA1019" SBAEAD-200LE
Reply:My vote is still a bad ground, either in the welder or at your panel.250 amp Miller DialArc AC/DC StickF-225 amp Forney AC Stick230 amp Sears AC StickLincoln 180C MIGVictor Medalist 350 O/ACut 50 PlasmaLes