Welding Cable Size for 200A (nominal) Inverter

[aesmith]

Hi,
The cables I have for Arc are a bit short at only 2m each for ground and rod holder, both 25mm2.
The MIG also included a rod holder, also 2m but only 16mm2. Both welders have 25/10 Dinse sockets.

My gut feeling is to stick with 25mm2 (I think that's max for those plugs). Would that be correct for cheap inverter, supposedly up to 200A, or would 16mm2 be just as good?

Also and related is there any problem using Dinse/Dinse extension lead, reusing one of the existing leads?

I suppose I'm assuming there's not going to be a problem simply from using longer leads. Maximum would be 9m total counting both supply and return.

Cheers

 

[hotponyshoes]

25mm Cable is about the biggest you cm physically fit into a 25/10 plug.

Advantages of bigger:
Bigger cable means less voltage drop over longer lengths although, unless you are running at maximum, you can just turn the welder up a bit to compensate.

Bigger cable will heat up less. Unless you are running hard constantly It's unlikely you'll ever melt a cable but heating/cooling cycles will degrade both the copper and the insulation so oversize cable will last longer.

Bigger cable is physically tougher. Has more conductors and thicker insulation so stands up to workshop abuse better.

Bigger cable usually works out cheaper in £/capacity. Ie, 50mm2 is cheaper per meter than 2 Lengths of 25mm2.

Downsides:
Higher initial cost (somewhat offset by higher scrap value at eol)

Heavier. Less flexible. More effort to coil and store.

Can put more strain on the machine sockets as you have more weight hanging off them.

Also:

Think about upgrading in the future. 16mm might well be fine now but might limit you if you want a bigger welder or need to do a big/long job in the future.

I am a overall fan of dinse extension leads.
My setup consists of several extension leads (male-female) between 4m & 6m.
They are all 35mm but I run upto 280a.

Advantages,
You can vary the setup, so if I am welding a trailer I can use a 3m ground lead and a 12m arc lead.
You only need the minimum length for the job so you do not have to drag unnecessary weight around or risk damaging cable unnecessarily.
They are easy to coil and store in shorter lengths.
If you damage the middle of a 6m lead you just cut out the damage, fit 2 connectors and gain 2x 3m leads!
Lower initial cost as you can just add to the collection when required.
You can use a lower cost cable for the extensions if you like. Then fit a shorter length of higher quality cable (flexibility & abrasion resistance) to the holder/clamp
I have 3 or 4 types of earth clamp so they just have 2/3m of lead on each then I extend as required.
You can then also fit trailing leads to stuff like tables, jigs, welding rotators that you just plug into an extension rather than have to fit the earth clamp when you want to use them.
Downsides,
The plugs/sockets can catch on stuff if you are trying to drag 3 coupled leads over a trailer chassis.
Plugs/sockets cost money.
If you don't have clean storage you may need to clean out the sockets occasionally and wire brush off the plugs.

In your shoes, I'd make up/buy some extension leads at least 25mm.
Plug your existing holder/earth into the end when required.
Then you can use your existing 16mm arc lead for access/flexibility/low fatigue and the 25mm one for the heavier jobs.

 

[zzr1200]

25mm cable is nice if you get the really flexible type.

Many many years ago I bought some yellow-ish twin rubber (butile?) shielded cable that was chemical/heat/oil resistance if I remember correctly.

Still using it for my inverter shoe box and it's really only very dirty, it's still in great condition, you get what you pay for.

5m earth cable 7m holder cable is my minimum suggestion

 

[aesmith]

Thanks. Good point about keeping the 16mm2 lead for light duty, the last job I was reaching around and under the trailer, but it was only 2mm rods @ 70A.

I also need to look at how bulky they are. It would be handy to be able to pack a set in the case with the MMA, but again these could be the 16mm2 if that's all that fits.

 

[hotponyshoes]

Depends on the cable.
Cheaper pvc cable is generally less bulky (smaller o/d) than more expensive rubber.
But it's less flexible (more memory effects) so the rubber is usually easier to store and handle.

Then there is the whole variety of other insulation & core types available...

 

[premmington]

I use 25mm cable in small dinse plugs.


Yeah you could get away with 16mm - but for the price difference - go larger...

 

[premmington]

25mm cable is nice if you get the really flexible type.

Many many years ago I bought some yellow-ish twin rubber (butile?) shielded cable that was chemical/heat/oil resistance if I remember correctly.

Still using it for my inverter shoe box and it's really only very dirty, it's still in great condition, you get what you pay for.

5m earth cable 7m holder cable is my minimum suggestion

I too always make stinger lead up longer than earth return.


7m and 5m is what I always spec up for workshop MMA welding leads. I also go to 4m for Euro mig torchs as well.

 

[aesmith]

Yeah you could get away with 16mm - but for the price difference - go larger...

Yeah, I'm not buying anything less than 25mm2. But I already have 2m x 16mm2 stinger and return leads that came with the MIG, so may use them in some situations.

 

[Ed.]

I personally, would stick with multi strand 25mm square cable preferably with the rubberized sheath (epdm)