Thread: Another stupid sparky question

Originally Posted by Michael G

What is the definition of a "flexible cord"? I have a 8m 3 phase extension cord that I use for my mill (20A). I've always wondered whether it should be replaced as while it flexes it looks more like the sort of cable you would strap to a tray.

I've wondered the same thing. I always thought it meant that each cable was a multi-strand cable, which is more flexible than if each were solid copper but also more prone to failure and voltage drop as a function of overall size.

Originally Posted by Michael G

Getting back to only being slightly off topic,




What is the definition of a "flexible cord"? I have a 8m 3 phase extension cord that I use for my mill (20A). I've always wondered whether it should be replaced as while it flexes it looks more like the sort of cable you would strap to a tray.

Michael

The definition of " flexible cords" realy revolves arround appliances..and as somebody quoted before runs out of puff at 4mm2.

I'll have to have a bit of a wade thru the standards to find the correct terms for heavier cables.......until a couple of years ago it was pretty common to see "orange circular" used for three phase extension cords and things like, connecting machines and wiring portable switchboards on construction sites....( hell I used to own an orrange circular 3 phase extension cord myself)....well the authorities came down on it like a tonne of bricks.......truth is it was never legal to use stranded cables in moving applications.

If the cable you have is ...orange.....stiff....and has a number of strands in each conductor you can count without taking your shoes off....it probably should not be used as a portable cable.

In sound and lighting, we regularly see three phase extension cords in the 30 & 40 amp range........the clipsal 32 or 40 amp 3 phase socket is pretty well an industry standard back stage.
The next step up the ladder is the blue 60 amp plug ( cant remember than brand) this is common in OB compounds & was broached as a standard connector by the ABC in the 80's for the commonwealth games & its stuck..pretty well.......wired up with 10mm2 flexible.....that takes a bit or rolling up

I'll have a wade thru the standards when I get the time.

cheers

Originally Posted by soundman

In sound and lighting, we regularly see three phase extension cords in the 30 & 40 amp range........the clipsal 32 or 40 amp 3 phase socket is pretty well an industry standard back stage.

That's what mine originally was - a 50A stage cable with clipsal fittings.

Originally Posted by Karl Robbers

Seeing as we are talking cables and plugs here, I thought I'd drop in this little gem.
I recently acquired a welder and when I unrolled the power cable, in among the rolls of cable was an adaptor lead. 20A male 3 phase to 32A female 3 phase, connected by around 4MM 3C + E flex. I surely do not need to go into dramatic detail about how naughty this is, nor the pitfalls of such practices, but you will never guess what else I found on the lead. A genuine, bona fide, super dooper test tag
This welder originally came from a large fabrication workshop that exports work both Australia and Worldwide. I cannot categorically say that it was they who set up the lead and had it tagged, but I doubt that the private citizen who I acquired the welder from, (cost a fortune too - a whole six pack of Boags Premium Light!), would have bothered with testing and tagging.

My (new from factory) 250amp mig came with a 2.5mm lead and a 15amp plug. I complained and they told me to rewire to 6mm twin&earth and send me a welding helmet to shut me up.
I since bought 6 meter of flexible black rubber cable in 6mm twin and earth and a clipsal 32 amp plug. the 2.5mm lead would have melted had I welded 10mm plate. The manufacturer logic? if people see the 32 amp industrial plug they wouldn't buy the machine. Yes, from the horses mouth.

As far as your adaptor, I must say that not long ago 4mm was rated for 32 amp and had been so for eons. It is now de-rated to 20 amp and you need 6mm for 32 amp.

Originally Posted by Marc

My (new from factory) 250amp mig came with a 2.5mm lead and a 15amp plug. I complained and they told me to rewire to 6mm twin&earth and send me a welding helmet to shut me up.
I since bought 6 meter of flexible black rubber cable in 6mm twin and earth and a clipsal 32 amp plug. the 2.5mm lead would have melted had I welded 10mm plate. The manufacturer logic? if people see the 32 amp industrial plug they wouldn't buy the machine. Yes, from the horses mouth.

As far as your adaptor, I must say that not long ago 4mm was rated for 32 amp and had been so for eons. It is now de-rated to 20 amp and you need 6mm for 32 amp.

I didn't have an issue so much with the 4mm cable as the 20A male to 32A female adaptor, particularly as the welder was rated to draw around 27A and the fact that it proudly wore a testing tag.

Nothing says success quite like excess, might as well as go the whole hog and get the extreme end of the spectrum. Quick google, first hit, they supply 20m 16mm2 63a extension cables, which are "ultra flexible" what more could you want?

Originally Posted by LordBug

Nothing says success quite like excess, might as well as go the whole hog and get the extreme end of the spectrum. Quick google, first hit, they supply 20m 16mm2 63a extension cables, which are "ultra flexible" what more could you want?

To find one on gum tree for 1/3rd the price.

I was looking for 3P extension cords for the mens and found an almost new 20M 32A Tenex extension cord for $80.
When I told him it was for a mens shed he made it $50!

Originally Posted by BobL

To find one on gum tree for 1/3rd the price.

Exactly. I paid $50 for 40m of 50A cable with Clipsal fittings. A bit rough and not tagged but integrity is fine. A secondhand stage cable with associated scuffing. I want more like that, not spending $500 for something similar.

Originally Posted by Karl Robbers

Seeing as we are talking cables and plugs here, I thought I'd drop in this little gem.
I recently acquired a welder and when I unrolled the power cable, in among the rolls of cable was an adaptor lead. 20A male 3 phase to 32A female 3 phase, connected by around 4MM 3C + E flex. I surely do not need to go into dramatic detail about how naughty this is, nor the pitfalls of such practices ...

I've been thinking about this. Supposedly my welder can auto-adapt to different input voltages. Given it has a 32A three phase plug, how else could I plug it into a house supply, other than with a patch cable like that? Sure, if I tried to pull 200A I would expect it to blow breakers but if I wanted to TIG 100A it should be fine. It's an academic question anyway, since my welding cart probably weighs a good 120kg and is hardly portable.

I would guess that you would be expected to fit the correct plug for the application.
Don't forget that if you halve the voltage supplied, then you need double the amperage to accomplish the same task.
Multi voltage machines are generally designed to cater for different markets rather than swapping on a regular basis or the use of patch leads.

Thinking about leads and plugs on an old Jetwelder I have. I acquired it from an Instrument section workshop that was closing about 18 years ago. It had been converted to single phase use when I picked it up and as I live on a rural block with a SWER power supply I left it as it was as no chance of getting three phase power where I live.
I use it from time to time as I have other welders I use more often. It has always worked ok so I have never changed anything, also not tagged but only used here in my personal workshop.
I will now try to attach a photo, first time for me on this forum.

That is a 3ph extension?. which one is the lead for the welder?
I had that type of plugs on an old Lincoln welder I bought second hand and replaced it with a clipsal. If the welder was converted to single phase you can change the plug to a single phase plug. What does your powerpoint look like?

Marc, Maybe my information was not clear enough. The lead from the welder is a thick orange cable connected to the male plug sitting on top of the welder. This plugs into the female plug next to it which is connected by a short cable to the three pin 240V plug shown. When I use this welder I plug it into a 240V 15A outlet. I only separated these for the photo. This adaption was done in the workshop by one of the electrical fitters as there was not always a suitable outlet available where some welding needed to be done.
I have not changed anything but I know I could fit a single phase 15A plug directly to the welder. I don't know how the orange cable is connected as I have never looked internally at this. It works ok as is so I haven't changed anything.
Regards

The picture a couple of posts up looks to be a simple 130 amp stick welder.

The plug arrangement is and always was illegal...as I have posted before..a lot of this sort of stuff happened in workshops in the past.

Now if this is a simple relativly low output stick welder, it is highly unlikly to be anything other than a single phase item.

Most likelyy it has beed wired to plug into a 3 phase outlet but only use a single phase.

So the question is...is it wired to run active to neutral...thus 240 V or active to active and thus 415V.

If it runs poperly via that butcherous adaptor from a standard single phase power point....I would be fairly sure that it is a single phase 240v welder.

What should be done is, a standard 15 amp plug and flex be fitted to the unit and the butcerous and illegal cable work scrapped.

cheers