grounding my engine driven welder

[Azphiks]

No short cuts here, got all new from top to bottom. Now need to ground the deisel engine to the truck frame as per owners manual. Only one problem: the welder is mounted on a cargo bed that will slide the welder out over endgate. Gonna see what me mechanic says, and the Cat dealer, but any advice from the pros would be much appreciated!

[Laiky]

A lenghth of cable connecting the two?????

[MAC702]

Flexible grounding strap preferred, or just a good piece of insulated STRANDED (for flexibility) wire. Insulated only so it doesn't unravel.

Please delete your post in the other forum since we've already started answering in this one.

[Bodybagger]

I'd use a length of small welding cable with copper lugs as it's unlikely to fray internally from flexing. If you are sliding the welder all the way off to drop off at job sites or hoisting it or whatever, I'd put a small Lenco twistlock connector in it so you don't have to constantly undo the bonding screw.

[SMTatham]

Well silly me.............have had...........several machines off and on different trucks and have yet to ground one to the frame.

[J hall]

I have to ask, Why ground the machine to your truck? Isn't it bolted down?
What do you think would happen if it wasn't grounded?
I'm not being a smartass, jsut bringing up a point. I have never, ever seen anything attached to the cute little ground lug that they put on welding machines.

[Sandy]

Just to add a bit to what Mac posted, this site shows what you may be looking for. Not saying to buy from them but this product type is what is most commonly used for your application and widely used in numerous similar applications.

http://www.electricmotioncompany.com/emc.php?type=bonding

[MAC702]

Well silly me.............have had...........several machines off and on different trucks and have yet to ground one to the frame.

I agree. But I couldn't tell from his stated design if his would clearly be grounded through the mounts. It might be being mounted to something that wouldn't conduct as well as the bolts. Figured I'd just answer the question about how best to use a longer, flexible conductor.

If it's clearly bolted to the truck or to all-conductive mounting system, I see no need for a strap.

[cruizer]

After going to All the brands tech schools, the only definative answer to the machines grounding bolt is for lightning strikes, say if the unit was on a skid on the actual ground, then you'd pound in a ground rod and connect that stud. That would prevent the electronics in the welder from being zapped.

Since the welder is already off the ground whilst on a truck isolated from the earth ground via your tires, there is no need to connect that stud bolt. We have had problems with Stupid inspectors that want an earth ground pounded in and that stud connected to it. Though now the welder isn't isolated, and different soil conditions would be more of a saftey concerns, as well as more likelyhood for lightning strikes.

[Sberry]

I would say its there possibly for premise grounding, none of which really pertains to the portable welder and it should be bonded to a work surface like the truck bed that has the possibility of becoming energized, GFCI would eliminate some concern but if the welder was insulated from this bed it needs the ground strap. If the outlet was mounted to truck and grounded thru a plug and cord this would be the protection. The bed has a possibility of becoming energized.

[MAC702]

Except tires don't stop lightning. Common false myth. The protection of staying in your vehicle is because you are wrapping yourself inside a metal skin that will conduct the lightning around you if it should strike your car.

[Sandy]

The subject in this case is really one of bonding, not grounding, correct? Making two separate pieces of metal electrically one and the same. Looking at any modern vehicle and there are bonding straps from the engine to the frame, quarter panels to the frame or quater panel to the firewall, battery to the frame, hood to the firewall, firewall to the frame, on-and-on-and-on. What in the heck makes a mounted engine driven welder/generator any different?

Not that it absolutely has to be, but what is the valid arguement for not doing it? If there is some safety or operational issue that might crop up by bonding then I'd like to hear it. The question was, after all, how to not whether to.

[Sberry]

What in the heck makes a mounted engine driven welder/generator any different? Thats a good question. I think it might be different as it would fall under some version of an electrical code, NEMA or highly likely OSHA. The bonding you talked about on the vehicle, say frame to chassis is basically for operation, maybe even protection of the property, the bond on the genset is for personnel protection. Genset has potentially lethal voltages.

[Sandy]

Thats a good question. I think it might be different as it would fall under some version of an electrical code, NEMA or highly likely OSHA.

You're correct there. In that post I was trying to look at things from the perspective of those who look at welders/generators as nothing more than a metal object and say "why bother".. I was wondering what the arguement against it is other than personal time and effort. From that perspective of bonding one object to another I really can't see any negative reason, electrically either.

In short, what can be said to NOT do it? I might be quick to say don't because it isn't safe or may damage equipment but I try hard not to say don't just because I don't or never have.

In fact electrically I can see some rare but possible scenarios where bonding might be a benefit. Not something I'd get paniced over but a point of debate never the less.

It's also been discussed from a code stand point as you suggest. Altho I've never been one to do something because "code says so" here's one reason that falls in that category. An interesting read to go with it.

It's one of four easy to acheive requirements that can relieve you of the responsibility of having to actually provide an earth ground while on a job site subject to inspection. Means little to flunkies like me, but then it very well may mean a lot to those who are safety and regulation conscious.



""CONDITIONS WHERE GROUNDING THE
GENERATOR FRAME TO A METAL
WATER PIPE OR GROUND ROD IS NOT
REQUIRED BY THE NEC:
1. The welding generator has auxiliary
power output (115 volts AC or 230 volts
AC) and the generator receptacles have a
ground pin outlet available for the
equipment that plugs into the receptacle,
AND
2. The generator is portable or mounted on
a truck or trailer, AND
3. The auxiliary power is used by cord-and-plug-
connection means through receptacles
mounted on the generator, AND
4. The generator is mounted on a vehicle
and the generator frame is bonded to the
vehicle frame.""

http://www.aws.org/w/a/technical/facts/FACT-29.PDF

As a side note in reading this document I see that even they drift across the line in their use of the terms grounding vs bonding. Grounding is grounding and simply connecting two pieces of metal together is 'bonding'. The old train of thought is slow to go I suppose.

[Broccoli1]

Except tires don't stop lightning. Common false myth. The protection of staying in your vehicle is because you are wrapping yourself inside a metal skin that will conduct the lightning around you if it should strike your car.

Mac- he said when the machine is on a Skid-direct contact with Terra Firma :)


Same rules apply here for Mobile Power-

"Generators mounted on trucks or trailers shall be completely insulated from earth by means of rubber tires, rubber mats around metal stairways and rubber mats under any type of lift-gate or jacking device. Metal supports for trailers shall be insulated by means of wooden blocks. Safety tow chains shall be secured so as to not touch the ground. If complete insulation is not possible, a grounding electrode system shall be installed per the California Electrical Code, Article 250-83 (c) or (d)."

[Broccoli1]

Well it is Bonding AND Grounding:) but because this is a Genset/Welder, folks forget that the Genset is the Power Source- Not the PoCo- so the Grounding is to itself- The Frame

The ground can be the earth (PoCo) or in the case of portable generators, the frame of the generator which will serve as a large conducting body that serves in place of the earth.

[Sandy]

The ground can be the earth (PoCo) or in the case of portable generators, the frame of the generator which will serve as a large conducting body that serves in place of the earth.

:D Yeh I see that. ;) Just doesn't make sense to call anything other than 'ground' ground. :) Altho in my tiny little world we do the same quite a bit, depending on who all is involved. If there is a chance for confusion then we try to referrence it to something such as 'frame ground', 'earth ground', 'case ground' and the like. Common language so to speak. Make sure everyone is talking about the same 'ground'.. :)

[Sberry]

4. The generator is mounted on a vehicle
and the generator frame is bonded to the
vehicle frame."" Right, bonded but no ground rod required. Seems to me in one of these codes I have seen some limitations to genset size also? Or does that refer to GFCI?

[griff01]

After going to All the brands tech schools, the only definative answer to the machines grounding bolt is for lightning strikes, say if the unit was on a skid on the actual ground, then you'd pound in a ground rod and connect that stud. That would prevent the electronics in the welder from being zapped.

Since the welder is already off the ground whilst on a truck isolated from the earth ground via your tires, there is no need to connect that stud bolt. We have had problems with Stupid inspectors that want an earth ground pounded in and that stud connected to it. Though now the welder isn't isolated, and different soil conditions would be more of a saftey concerns, as well as more likelyhood for lightning strikes.


Tires being an insulator is a common misconception. The main ingredient in tires is "carbon black". It is in itself a good conductor. When mixed with other chemicals the conductivity is reduced but is still present.

Griff

[cruizer]

Yep, that why I said "more likelyhood of lightning strikes" when using a earth ground stake. Anyways, all welders have thier neutral bonded to the welder frame, leastwise all in the last 15 years or so.

[MAC702]

Yep, my mistake. I read it wrongly. Thanks.

[Broccoli1]

More info :D:D

http://159.105.83.167/Portals/0/WP%20Safety/Portable%20Generators%20qnd%20OSHA%20Construction% 20Standards22.pdf

[Sandy]

More info :D:D


:)Man o man, is it easy to see how easy it is to get side tracked on terminolgy. :)

[MAC702]

I think it's more of a "tangent" than a "side track"... :p

[JTMcC]

Tires being an insulator is a common misconception. The main ingredient in tires is "carbon black". It is in itself a good conductor. When mixed with other chemicals the conductivity is reduced but is still present.

Griff


I've worked many a day/night up in the banberry's (just above the mills), where all of the raw ingrediants going into the tire are mixed. Lamp black is certainly a portion of the mix but not by far the "main ingredient" in the plants I worked in. Every tire recipe I saw go down the (short) conveyor into the banberrys was mainly real rubber, next was synthetic rubber, then lamp black (or carbon black) plus a lot of top secret things in very small amounts.

You can go home and shower for an hour, and when you next start to sweat the carbon black comes out of your pores ; ), lot's of OT to be had there tho no place for slackers.

JTMcC.

[JTMcC]

Post number 15 clearly states that the tires do in fact insulate. Other posts dispute that.

Tomorrow morning i'm going to max out my biggest welding machine, at about 515 amps, hook the stinger and the ground to an automobile tire and see for myself :)

Results to follow. Same bat time, same bat station.

JTMcC.

[MAC702]

I'll make sure to clarify that my post was in regards to lightning, which is far higher voltage than welding machines or line voltage to a typical residence or from a typical generator.

I will agree that typical tires are adequate insulation for these things. All insulation is rated for a specific voltage; amperage SHOULD be irrelevant.

If the voltage is high enough, ANYTHING can conduct. Okay, maybe I shouldn't say "ANYTHING," but you get the idea.

[BC_Hardwire]

JTMcC !!
I hope you dont try this tire experiment with it fully inflated! :eek:
Kaboom!

[Sandy]

I'll make sure to clarify that my post was in regards to lightning, which is far higher voltage than welding machines or line voltage to a typical residence or from a typical generator.

I will agree that typical tires are adequate insulation for these things. All insulation is rated for a specific voltage; amperage SHOULD be irrelevant.

If the voltage is high enough, ANYTHING can conduct. Okay, maybe I shouldn't say "ANYTHING," but you get the idea.

Exactly. Tires aren't classified as a conductor for sure. Most individual insulators on local power distribtution aren't rated much above 16kva new. That's why they are configured in stackable bells so they can add bells for more air gap at high potential locations. At some point it doesn't matter what the insulation factor is, high enough voltage is going to jump the gap anyway. Tires only provide so much gap between the vehicle and earth.

My guess is that a high profile, clean, dry, and non-steel belted tire is a better insulator than a low profile, dirty, wet, steel belted tire any day. ;)

[JTMcC]

I messed up today and let work interfere with my mad scientist duties.
Tomorrow I shall attempt to bring the tire to life!

JTMcC.

[Broccoli1]

I messed up today and let work interfere with my mad scientist duties.
Tomorrow I shall attempt to bring the tire to life!

JTMcC.

http://i210.photobucket.com/albums/bb122/EdConley/JTMcC.jpg

[JTMcC]

Broccoli 1 you can mock me, make fun of me, ridicule me all you want.......now.

But you will be strangely silent when the day comes that I AM ruling the world from my secret laboratory.

JTMcC.

[JTMcC]

I maxed out one of my machines, at 507 measured amps, and put the leads to the right front tire. The tire exploded, ripping the front fender half way in two and bending the shock absorber and drag link.
The tire then caught fire and set my mustache and shirt on fire. While I was putting that out the truck became fully engulfed, the fuel tanks on the truck and the machine were almost full, and blew fuel onto my front porch, igniting the house. Both oxy bottles let off, fueling the house fire further, the shack was burnt to the ground.
When the acytelene bottles went, they launched, one landing a quarter mile away on the neighbors roof, another total loss. It doesn't matter tho as the wildfire started by the other acy bottle would of burned both houses down anyway. That's the only bright spot.






J/K. Nothing happened. Absolutely nothing. Back to the drawing board.

JTMcC.

[griff01]

I've worked many a day/night up in the banberry's (just above the mills), where all of the raw ingrediants going into the tire are mixed. Lamp black is certainly a portion of the mix but not by far the "main ingredient" in the plants I worked in. Every tire recipe I saw go down the (short) conveyor into the banberrys was mainly real rubber, next was synthetic rubber, then lamp black (or carbon black) plus a lot of top secret things in very small amounts.

You can go home and shower for an hour, and when you next start to sweat the carbon black comes out of your pores ; ), lot's of OT to be had there tho no place for slackers.

JTMcC.

You are right on the carbon black coming out of the pores. For days!!

The carbon black does not go "down the short conveyor" though. It is dropped directly into the mixer (banbury) via a chute as it would not stay on an open conveyor.

Also, there is less "real rubber" (natural rubber) than carbon black in a modern tire.

I have never seen lamp black used in any tire mix.


Griff

[JTMcC]

Tires being an insulator is a common misconception.
Griff


I still don't agree with that. I know they won't conduct 500 amps at around 30 volts, and won't conduct 120 v at whatever amperage household current comes out at.
Maybe they will magically conduct 220 or 440 but my experiments with tires and electricity are over for now.

The term "lamp black" is used interchangably in my experience with "carbon black" in the plants, I have no doubt you are right that it is incorrect usage, but I refere to carbon black in both cases.


JTMcC.

I haven't worked up in the banberrys for several years, but the memories remain strong ; )
The smell reminds me of money.

[griff01]

I still don't agree with that. I know they won't conduct 500 amps at around 30 volts, and won't conduct 120 v at whatever amperage household current comes out at.
Maybe they will magically conduct 220 or 440 but my experiments with tires and electricity are over for now.

The term "lamp black" is used interchangably in my experience with "carbon black" in the plants, I have no doubt you are right that it is incorrect usage, but I refere to carbon black in both cases.


JTMcC.

I haven't worked up in the banberrys for several years, but the memories remain strong ; )
The smell reminds me of money.

I do admit I am splitting hairs with the terminology on the tires not being an insulator, rather a poor conductor.

And you are indeed correct about the memories and the smell!!!

Griff

[JTMcC]

Griff01, do you work in a tire plant?

I spent some precious time in Goodyear plants (working for contractors). My Father in law retired as an electrician/electronics dude after 38 years for GY, now he instructs in their electical apprentice program run thru the local University.

JTMcC.

[JTMcC]

You should give up on welding for a living; you’d make more money as a comedian! :cool::D:D:D


Thanks for the advise, but I'm afraid the rugrats would soon be starving if I took that course ; )


JTMcC.