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View Full Version : 2ga welding cable vs 2ga battery cable



Aric
08-01-2006, 11:55 AM
I need a new set of arc welding leads, nothing too long maybe 25ft.
Is there adifference between welding cable and battery cable? I'm under 200amps with this machine.

smithboy
08-01-2006, 12:09 PM
If they are the same gauge, I don't think there is any differnce in the wire, except for maybe the way it's braided...some jumper cable wire uses really thin strands to make it really flexible. My welding cables use thicker stands, so they are not as flexible. One thing that could be pretty different is the coating. I imagine most welding cable has pretty thick, fairly heat/spark resistant coatings, whereas jumper cables may not require that.

With all that said, I know of lots of folks who have used heavy jumper cables to do off-road welding and never had any problems.

tapwelder
08-01-2006, 12:29 PM
I use audio cable. It uses finer strands of wire to acheive the same guage. Though the coating is not as flexible. Especially when it gets cold. The stuff gets heavy when you got to stretch it out at 200 feet.

I would assume for like guages the coating is the major difference between battery cable and welding cable.

If you are debating then go with welding cable if you are going to use it for daily welding work.

MAC702
08-01-2006, 12:43 PM
When you say battery cable, are you talking about jumper cables or cable designed for permanent installation in your car between the battery and starter? The latter is very stiff because it has much larger strands because it doesn't need to be flexible.

The other issue is the insulation. Welding cable has a dual-purpose insulation and jacket that protects against constant abrasion. Cables designed for permanent installations are insulated, but they are not intended to serve the dual purpose of protection against constant abrasion.

Lockdown
08-01-2006, 02:12 PM
Big difference in Welding cable vs Battery cable.

1) The actual surface area of wire of Welding cable vs Battery Cable is much much greater for the welding cable. More surface area = less resistance = better voltage = more amprage = happier welders

2) I don't know what type of Welder you have, but most the time Battery cable is designed for DC currents (higher heat vs AC current) whereas Welding cable (if the power cord from the outlet) is AC current which is actually less heat.

3) Also what type of amprage are you pulling so that you need 2 ga? Pretty thick crap.

MAC702
08-01-2006, 02:23 PM
Big difference in Welding cable vs Battery cable.

1) The actual surface area of wire of Welding cable vs Battery Cable is much much greater for the welding cable. More surface area = less resistance = better voltage = more amprage = happier welders

2) I don't know what type of Welder you have, but most the time Battery cable is designed for DC currents (higher heat vs AC current) whereas Welding cable (if the power cord from the outlet) is AC current which is actually less heat.

3) Also what type of amprage are you pulling so that you need 2 ga? Pretty thick crap.
1. This difference is not nearly as great as you might think it is. The greatest reason by far for smaller stranding is the greater flexibility of the cable. For example, Table 310.16 (Ampacities) of the NEC makes no distiction between solid conductors and 19-strand conductors.

2. All but the cheapest AC buzzboxes are usually DC welders, including Aric's Miller engine-drive, if this is the unit he's looking to outfit. Again, with ambient temperatures and a welder's duty cycle (the machine AND the person), this difference is negligible.

3. #2 welding cable is actually one of the smallest available welding cable sizes and is recommended for 200A in lengths up to 50 feet, or 100A up to 200', regardless of process or polarity.

awright
08-01-2006, 03:16 PM
Lockdown, I think you are confusing surface area with cross-sectional area of conductors. At DC and line frequencies, cable resistance is purely and simply a matter of total cross-sectional area of copper (as well as the specific alloy of the copper), independent of the number of strands making up the cable. As MAC702 says, the reason for a large number of very small strands in welding cable is for maximum flexibility, which is also related to avoidance of fatigue-induced breakage at connectors.

At very high frequencies (which may include HF arc starting frequencies) a phenomenon sneaks into the situation called "skin effect," in which the electron flow is repelled from the center of the conductor strand and clusters along the outer surface of the individual strand. In this situation, the center region of the strand does not carry as much current as the skin, resulting in a higher effective resistance of the strand. This phenomenon arises at very high radio frequencies and has no bearing on welding cable performance.

Another phenomenon that might come into effect is heat dissipation ability of different cable types. This could get pretty complex to analyze as a heat transfer calculation and I have no idea what the result would be regarding the performance of various cable types. Simplistically, a larger cable O.D. results in larger surface area for transfer of heat to the air, possibly giving an advantage ot welding cable. On the other hand, thicker insulation would impede heat transfer from the copper to the air. An additional factor would be the thermal conductivity of the insulation material. My personal bias would be to trust the welding cable manufacturers to properly balance out all these factors.

Perhaps if people are considering alternatives to welding cable for economy they could consider using cheaper cable for semi-fixed, long runs that are not dragged around, walked on, driven across, subjected to sparks, spatter, and ozone, etc., as is most welding cable, then use shorter stingers of welding cable on the working end of the long, protected, run.

Additionally, there is no difference in heating of the cable between AC and DC current of a given RMS (Root Mean Square)amperage. RMS amperage is always implied in statements of AC current unless otherwise noted for some very unusual reason. The RMS value of DC current is the same as the average or the "DC current."

awright

zapster
08-01-2006, 04:49 PM
i've used jumper cables "clamp to clamp" when the ground was not long enough...
no biggie..

...zap!

prop-doctor
08-01-2006, 06:42 PM
I too have used jumper cables for the grd. in my tig work --and have used them in a quick fix on arc as the stinger ---but wouldn t do it every day .. the as the ground it works

Lockdown
08-01-2006, 07:07 PM
Lockdown, I think you are confusing surface area with cross-sectional area of conductors. At DC and line frequencies, cable resistance is purely and simply a matter of total cross-sectional area of copper (as well as the specific alloy of the copper), independent of the number of strands making up the cable. As MAC702 says, the reason for a large number of very small strands in welding cable is for maximum flexibility, which is also related to avoidance of fatigue-induced breakage at connectors.

Maximum surface area in my mind cross-sectional area. Also I'm talking about from the OUTLET to the WELDER (AC Power). Not from the WELDER (DC Power) TO THE GUN. Sorry for the caps just making sure thats what your commenting on.


At very high frequencies (which may include HF arc starting frequencies) a phenomenon sneaks into the situation called "skin effect," in which the electron flow is repelled from the center of the conductor strand and clusters along the outer surface of the individual strand. In this situation, the center region of the strand does not carry as much current as the skin, resulting in a higher effective resistance of the strand. This phenomenon arises at very high radio frequencies and has no bearing on welding cable performance.

Yes your correct, electrons flow on the outside of the wire, not on the inside.


Another phenomenon that might come into effect is heat dissipation ability of different cable types. This could get pretty complex to analyze as a heat transfer calculation and I have no idea what the result would be regarding the performance of various cable types. Simplistically, a larger cable O.D. results in larger surface area for transfer of heat to the air, possibly giving an advantage ot welding cable. On the other hand, thicker insulation would impede heat transfer from the copper to the air. An additional factor would be the thermal conductivity of the insulation material. My personal bias would be to trust the welding cable manufacturers to properly balance out all these factors.

Larger OD = more area to disipate heat inside the wire and out, but again heat dissipation is not the most important issue of the wire. The issue is, at a certain amprage, at time "X", at length "Y", how long will that wire survive before the wire seperates and what would be a safe design factor? I doubt the engineers of wire are overly worried about having adaqute air flow or heat dissapation through a S.O. cable.


Additionally, there is no difference in heating of the cable between AC and DC current of a given RMS (Root Mean Square)amperage. RMS amperage is always implied in statements of AC current unless otherwise noted for some very unusual reason. The RMS value of DC current is the same as the average or the "DC current."

RMS Amprage is one thing, but using a AC designed wire on a DC current has always been taught to me as a no-no thing to do simply because the DC current will create more heat due to not alternating and giving a "breather" time.

Aric
08-01-2006, 08:49 PM
I wasn't thinking jumper cable wire. something like this:
http://cgi.ebay.com/ebaymotors/2-GAUGE-AWG-BATTERY-WIRE-CABLE-20-Feet-BLACK_W0QQitemZ140013197196QQihZ004QQcategoryZ3357 4QQrdZ1QQcmdZViewItem

This stuff too stiff? It is for the miller Bluestar DC engine drive. Mostly as a second set of leads, because over the weekend the welder ended up in one truck and the leads in another :(

Sober_Pollock
08-01-2006, 09:10 PM
AC Wire? DC Wire?

I'm an industrial electrician who works on AC variable frequency drives and DC variable speed drives. Up to 1000 (Thousand) horspower. Every day.

You guys are losing me with the AC wire and DC wire?

MAC702
08-01-2006, 09:39 PM
AC wire v. DC wire? Is there some difference in the copper alloy that I don't know about? RMS value has EVERYTHING to do with this. And the point is that this is ALL WAY OUT OF THE SCOPE of the OP.

And yet you want to say that surface area is the same as cross-sectional area in your mind. I must be missing something you're trying to say.

And since the OP is asking about welding leads, not AC power leads to the machine, why did you bring it up in the first place?

MAC702
08-01-2006, 09:52 PM
I wasn't thinking jumper cable wire. something like this:
http://cgi.ebay.com/ebaymotors/2-GAUGE-AWG-BATTERY-WIRE-CABLE-20-Feet-BLACK_W0QQitemZ140013197196QQihZ004QQcategoryZ3357 4QQrdZ1QQcmdZViewItem

This stuff too stiff? It is for the miller Bluestar DC engine drive. Mostly as a second set of leads, because over the weekend the welder ended up in one truck and the leads in another :(
It would be for me! You pays your own money and makes your own sacrifices, though...

Sober_Pollock
08-01-2006, 09:55 PM
Not being a welder expert, I would like to know the open circuit voltage that blue star is capable of.

The wire in that E-Bay listing says it is rated for 50 volts or less. This would be a function of the insulation it has on it. In other words, the insulation on this wire might not be up to the voltages this welding machine can produce.

This would make all the rest of this discussion a moot point.

Although, I still want to know the difference between "AC wire" and "DC wire"

OH, and by the way, since this is an engine driven welding machine, it does NOT have an AC power cord, which makes that whole discussion moot also!

MAC702
08-01-2006, 10:06 PM
Excellent point. I don't find the OCV listed in the specs sheet for the current production, but it COULD be as high as 70 - 80V. I'll check the manual.

There is no difference in (in fact there is no such thing as) AC or DC wire. If you are measuring the peak values of AC amperage, it will be higher. Which means a 480A DC load has the same heat in the wire as a 600A AC load, and can use the same wire. Except we measure RMS values of AC amperage anyway, so that brings us right back to the same 480A, regardless of polarity. My best quick attempt at a nutshell.

MAC702
08-01-2006, 10:09 PM
Excellent point. I don't find the OCV listed in the specs sheet for the current production, but it COULD be as high as 70 - 80V. I'll check the manual.
The manual for a Bluestar 185 DX shows the OCV to be between 62 and 76V, depending on the settings.

Sober_Pollock
08-01-2006, 10:52 PM
The manual for a Bluestar 185 DX shows the OCV to be between 62 and 76V, depending on the settings.

That's kinda what I was figuring.

Aric, stay away from that cable on E-Bay. (Unless of course your making battery cables)

The insulation isn't adequate for use as welding cables. I'm betting that you'll run into this a lot with "Battery" type cables having lower voltage ratings since they're usually meant for lower voltages.

Watch that insulation rating.

Sober_Pollock
08-01-2006, 11:05 PM
There is no difference in (in fact there is no such thing as) AC or DC wire. If you are measuring the peak values of AC amperage, it will be higher. Which means a 480A DC load has the same heat in the wire as a 600A AC load, and can use the same wire. Except we measure RMS values of AC amperage anyway, so that brings us right back to the same 480A, regardless of polarity. My best quick attempt at a nutshell.

Sure Mac, rain on my parade, I was fixin to have some fun with that one!:laugh:

I once sent a purchasing clerk to an electrical supply house with a list of stuff to get that included "Three Phase LU400 High Pressure Sodium Light Bulbs".

The worst part was that the guy behind the counter, without batting an eye, said "We're all out of them" and sent her to another supply house!

By the time she got back, she was mad enough to kill me.

Sandy
08-01-2006, 11:10 PM
For what welding leads go through over a span of time, I wouldn't mess with anything less than standard 300/600 volt insulation. They get trampled on, molten splatter, drug across sharp shavings, wrapped around hot steel, left in the sun and all kinds of use and abuse. Start off with minimal insulation and it won't be long before your bringing worms to the top every time you run a bead just because of leakage. :)

Washman
08-02-2006, 12:59 AM
Wow !

Some of you guys really put a lot of intelligent thought into this cable discussion. I must say I'm impressed with the research and amount of knowledge put forth in your answers.

But I think perhaps ya should have just told him battery cables were made for batteries and welding cable was made for welding. Special made for a special purpose.

Sorry dude ... I personally understand Welding cable is pretty expensive stuff!

But it's the best thing for welding. It has been properly designed and manufactured for the welding industry.

Use Welding cable for welding... Battery cables for Batteries

Don't be cheap this is not a good place to save money! Sorry if I hurt your feelings I don't mean to, just telling it as I see it.

Washman

wizard
08-02-2006, 01:02 AM
Well all this talk about current and voltages is well and good but one thing that I've not seen mentioned here is the Quality of JUMPER cables. You can buy good ones if you know where to dhop or you can buy junk. Honestly all the welder needs is a low impedance path to the work piece, some JUMPER cables can't even provide that for motor starting much less anything else. Interestingly the chepa cable oftne don't evne mention the gage of the wire, nor the make u of the rest of the components.

As to other battery cables that you might buy at an electrical supply house in bulk, electrically they will perform just like the same gage welding cables. What they won't do is perform mechanically like a set of welding cables unless you are real careful about insulation specifcation. There is also the issue of mechanical flexibility of the actual conductors and the temper of those conductors.

You can get flexible cables or stiff cables. The cables flexibilty is the result fo the combination of the flexibility inherent in the conductors and the inslutation. Alll of this varies with temperature..

What it all boils down to is that you get what you pay for. The cable manufactures go to the trouble of making welding cables for a good reason. Lets face it the market for weldign cables isn't that huge, there has to be a pay off for the manufacture to go about making special products like welding cables.

Dave

wizard
08-02-2006, 01:19 AM
For a fisheman that may be reason enough to call it a day and scopp up those worms.

Thanks for the humor Sandy

Dave




Start off with minimal insulation and it won't be long before your bringing worms to the top every time you run a bead just because of leakage. :)

Aric
08-02-2006, 10:52 AM
thanks eveyone.

Lockdown
08-02-2006, 01:47 PM
And since the OP is asking about welding leads, not AC power leads to the machine, why did you bring it up in the first place?


SORRY READ THE ABOVE QUESTION WRONG. Please don't throw rocks at the box I live in... I was wrong apologize. :sleeping: :blush2:

onefastduc
08-02-2006, 02:33 PM
Aric,
Is this what you are looking for? Good Price.

http://cgi.ebay.com/25-ft-1-Guage-Black-Welding-Cable-New_W0QQitemZ320013281796QQihZ011QQcategoryZ67042Q QrdZ1QQcmdZViewItem

MAC702
08-03-2006, 01:28 AM
SORRY READ THE ABOVE QUESTION WRONG. Please don't throw rocks at the box I live in... I was wrong apologize. :sleeping: :blush2:
We all do it. No biggie. We're glad you're here, and keep on contributing!