Thread: Another stupid sparky question

Thank you Marc and Karl for your comments. When I posted the original photo I expected a response but it took a while.

The instrument workshop was at a power station in Qld and the adaption connection was probably done in the 1980s and I acquired the welder in the mid 1990s. I have other welders as shown on another topic I started so I rarely use this one, only when it was the closest to where I was welding. Now I won't use until I get a proper plug and cable.

I took some photos of the only information plates on the welder, one on the front and one on the back. I will attach them for your information.

Ahh yes as we suspected a straight forward single phase welder.

entirely suitable for a 15 amp circuit.

Don't let a bit of past dodgyness putt you off what was and probably still is a damn fine stick welder.

Give us some pictures of the cable that is fitted.....it may well be that it is the factory original cable..and if in good condition, may simply require the fitting of a normal 15 amp plug top.

Yanks being yanks...they may have gone overboard on the cable......have a look at the diameter....it may fit into a standard 15amp heavy duty plug top...this is the one with the standard soft plastic back cover...the HD version has a larger cable entry.

Otherwise you may have to go to the industrial style plugtop...still conventional 3 pin form but with a hard plastic backshell and a cable clamp.

If the whole cable looks a bit dodgy..and you don't want to be far from the 15 amp outlet...the chepaest option is to buy an off the shelf 15 amp caravan lead and chop the socket off....it will cost you less than the same length of 15 amp cable and a plugtop.

Don't forget to cross the T's and dot the I's and make sure it gets a good look over and Test & tag.

They simply don't build welders like that any more.

cheers

Sorted. Made in Australia into the bargain.
The plate states 40x.076 cabling which is near 3mm, so if you use 4mm flex you will be laughing.
As an aside, I was in at my friendly welder repairer today picking up my Transpulse 350 and there in a pile were a heap of leads that were condemned after inspection. They were the good old orange 3C+E building cable.
Now if they can just catch up with the motor rewinder down the road that has 6" nails for his main supply fuses.......
For a laugh.
guide to fuse replacement.jpg

[QUOTE=Karl Robbers;1817271]
The plate states 40x.076 cabling which is near 3mm, so if you use 4mm flex you will be laughing.


The plate actually says 40 x .0076 which I assume would be inches, it works out to be quite small so 3 or 4mm would be fine.

Its a 15 amp machine, so using the guidelines I posted above, standard 1.5mm2 three core flex will be just fine in shortish lengths.


From memory that is 30/0.25.mm

Its a high start current 15 amp application.

If you wanted to go beefy, you could go 2.5mm2 and that should fit in a 15 amp heavy duty plug top properly.


here is another bit of information.

as long as the cable is Australian approved flex you can establish the cross sectional area by counting the strands.

24 strands at 0.20....is 0.75mm2 or 7.5 amp flex
32 strands at 0.20...is 1mm2 or 10 amp flex
30 strands at 0.25..is 1.5mm2 or 15 amp flex
50 strands at 0.25...is 2.5mm2 or 20 amp flex
56 strands at 0.30..is 4mm2 or 25 amp flex.

To be australian approved it must conform to the stranding...the intent is that the cable can be identified by counting.

so you strip the cable back and count the strands......that was part of the trade test back when I sat for my licence.

These days though most cable has it all printed on it every foot or so.....most is moulded...though, some is printed in ink, which can come off in use and cleaning.

Note that below 1.5mm2, the current raring is 10 amps per mm2..above that there is a thermal mass issue that meand there needs to be a derating.

cheers

[QUOTE=Techo1;1817289]

Originally Posted by Karl Robbers

The plate states 40x.076 cabling which is near 3mm, so if you use 4mm flex you will be laughing.


The plate actually says 40 x .0076 which I assume would be inches, it works out to be quite small so 3 or 4mm would be fine.

Oops, my mistake. That makes it closer to 1.2mm.
For what it is worth, I would still put a nice chunky lead on the old girl. Welders like their juice.

Sorry to harp on the matter but just to clarify.

If you look at the second spec plate in the post above.

ASC97-1964 is referenced at the top of the plate...that will be a government or military standard that predates Australian standards as we now know them...it also dates this machine to the late 60s or early seventies..in the pre metric period.

The plate gives a rated current consumption of 12 amps.....which is what it would consume averaged in normal continuous welding at the full rated output of 130 amps.

It state the Maximim short circuit current draw is 29 amps...that is how much it would draw with the dial all the way up and the rod firmly stuck.

Most electrical appliances draw considerably more than their rated input current for short periods.....this is why standard circuit breakers are specificed as holding at twice their rating for a full 60 seconds

So it is well within the 15 Amp format.....

If the guidelines I mentioned earlier in this thread are followed......( for high start current applications)15 meters or less of 1.5mm2 cable there will be less than 5% voltage drop in the cable.

Personally I would keep the mains cable on a welder under 5 meters it gives plenty of flexibility to get the machine near the job and a cable that is short enough to manage.

The biggest that is practical is 2.5mm2, because that will fit properly in standard 15 amp heavy duty plug tops.

I'd still keep the cable at 5 meters max.....remember you need to have that cable unrolled and laid out when working with the welder for heat reasons.

cheers

Originally Posted by soundman

I'd still keep the cable at 5 meters max.....remember you need to have that cable unrolled and laid out when working with the welder for heat reasons.

cheers

Excellent advice.
If you look at welders in an industrial setting, they always put the welder close to the power outlet and extend the work and electrode leads as required. Lincoln for example list tables of lead sizes required for runs of up to 70 odd metres.

Yeh well I would not say that it is wise to run long runs of electrode leads much of the time.

In the past...in the days of big heavy iron bassed welders, long welding cables where pretty common because it was just not practical to drag a big heavy welder all over the job.

But these days, in the age of electronics and welders that weigh less than a lunch box.
Running 240V cabling becomes more practical.

In the past on big workshp structures and on site building welding.
The welder sat on the ground and moved very little and blokes dragged big heavy leads up the ladders and all over the scaf.

These days the tradesman has the welder slung over his shoulder and the earth and electrode leads may be as short as 2 meters.

Running the majority of the length in 240V flex will be a hell of a lot cheaper and more practical that running serioulsy heavy welding cables.

Keeping all cables as short as possible will always improve welding perfomance......but there are limits of practicality.

Almost without exception welders and all tools as manufactured have minimum length leads fitted.....purely on a cost basis.

It will be rare to see a new welder fitted with any less or any more than 1.2 meters of mains cable ( 1.5 if the factory is being generous)...because that is the absolute mimimum practical and the minumum required by the standards.

Of course many welding manufacturers and welding suppliers will recommend the use of long, big heavy welding cables.....because they will make good money selling them, where they would be unlikly to get any sale at all, if 240v flex was used.

Arround the average workshop, 5 meters of cable will allow getting the welder closer to the job without either getting in the way or hampering performance.

Longer than that and you need a good heavy extension cord.


Then we get the pretty well universal reccomendation against using extension cords with things like welders and compressors.

There is absolutly no reason why extension cords should not be used with welders, compressors and other high demand machines......AS long as those extension cords are of adequate size and properly managed from a safety point of view.

Consier those tables I posted earlier and that they are bassed on 5% maximum voltage drop.

As it stands all my welding & cutting machines have factory fitted cables, and I use a 20 amp 2.5mm extension cord to get to where I want to work.

A 5 meter cable on those machines would get me to where I want them......they may well get them when they come out of warranty and I have the time and inclination.

If I was running a stick welder on something like a trailer frame...yes I would still use long heavy earth and electrode leads, purely because it is not practical to drag the machine all over the job and I do not have a lunch box stick welder.

cheers

Had a bit of time recently so took the cover off the Lincoln Jetwelder featured in some earlier posts. Not a lot of welder inside the space but works ok. Removed the power supply cable but took the attached photos before. Some dust inside and quite a few mud wasp nests which is normal in this area, which means every small cavity or space in equipment has to be covered or plugged. Even a compressed air blow gun will be blocked if not used for a week or so.
Anyhow to get back to the welder I expect to get the power lead replaced with new lead with a 15A plug.
Some of the insulation around the transformer appears a bit brittle but nothing major.

Photos show general inside views including power cable connections and other end of cable that came out of the original 3 Phase plug. Also a couple of views of the welding current selector. Comments welcome.
Regards, Normanby

Many years left in the old girl yet.

Interesting..its a tap change welder rather than a reactive slug welder.

Limited settings...but that is less of a problem than some think.

There are a few things that need a bit of a clean and tidy.....but with a little attention and a new mains cable you'll get another 30 years out of it no worries

Two things that are a little concern.

I'd prefeer to see the welding cables terminated on either binding posts or moder twist connectors...easily done...this would give more options on welding cables used and be a little more robust

Note that the neutral wire is not in the terminal block with the active.......seems that this neutral wire to the transformer has broken short at some time.
Some sort of better arrangement would be nice.

a screw up gland and a P clamp would be good for the mains cable entry.....two nuts on the earth screw is the old specifcation...but that seems to have been dropped in the stsndards....still a good idea.

cheers

Originally Posted by soundman

Interesting..its a tap change welder rather than a reactive slug welder.

Limited settings...but that is less of a problem than some think.

I am guessing that this is the Australian made version of the Lincoln tombstone welders.
As far as I can gather, the Jetwelders were a very basic entry level machine, but as with most equipment from that era, were built to the same standards as thir flagship range.
Stud or Binzel type outputs would be a nice touch with the Binzels probably being the cheaper option, (use 35/50's in preference to the smaller 10/25's).
The duty cycle of that machine could easily be improved by the addition of a cooling fan and venting if desired as another upgrade.