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We normally get 20+ 2.5mm rods out of a full charge on our Lorch sets and as we have 3 in the building we can always borrow another battery to finish the job
- Thread starter balmerchris
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We normally get 20+ 2.5mm rods out of a full charge on our Lorch sets and as we have 3 in the building we can always borrow another battery to finish the job
Badger1bear
If your not on fire, then your too far away
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Kemppi advertise their minarc mig 200 as being able to run off of a 100 mtr extension lead. With the idiots in our place I would not run a huge extension lead because they would run over it !
Now if you had said pedestal rotary arm pillar mag drill that would of been a different matter because that needs a 14.3 amp fuse, I will see if I can dig a picture out
Now if you had said pedestal rotary arm pillar mag drill that would of been a different matter because that needs a 14.3 amp fuse, I will see if I can dig a picture out
rtbcomp
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https://en.wikipedia.org/wiki/Oxyhydrogen
http://www.watertorch.com/faq/faq2.html
Google "Browns Gas" Welding
daleyd
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Not as a commercially available and viable solution to weld steel (I believe the gas is sometimes used in some aspects of jewellery manufacture), I'm happy to be corrected if you can provide a credible link though
Note the keywords there^^
brightspark
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depending on what type of cable used at 100 meters it will be roughly 1kw using 2.5 cable 2 kw 4.0mm
Presumably when running off mains, the portable battery welder only needs a light duty mains cable, as it will be able to charge up 100% of the time whereas you are welding intermittently. So even a long thin mains cable shouldn't be a problem ?
brightspark
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correct
that's It in a nutshell. if u want it at 200 meters there's no problem as long as u double the csa size of cable .eg 6 or 10mm and use a joint box and reduce the beginning to 2.5mm to fit the 13 amp plug 
MattH
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But all your comments are based on your 17th edition experience of acceptable voltage drops in circuits.
This is a portable appliance and as said can probably very easily deal with a 5-10% sag that would be totally unacceptable in fixed wiring.
Why's it so hard to believe? The literature that Richard referenced didn't say the welder can be supplied with a 100m cable with no supply voltage drop (and no one is arguing it would), it said with such a setup there would be no output current drop.
It's an inverter an to a certain extent it doesn't care about the exact input voltage as the first thing it is doing is rectifying it to DC.
rtbcomp
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It may be able to accept a lower voltage, but to deliver the same power it will have to up the current, which will cause a further voltage drop, and so on until the inverter stops or the cable overheats.
Being able to run on a lower voltage assumes that the extra input current will be available, which wouldn't be the case on an under-specced extension.
Being able to run on a lower voltage assumes that the extra input current will be available, which wouldn't be the case on an under-specced extension.
MattH
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That's assuming it's maxing out the available current on a short lead to start with.
It's not out of the realms of possibility that Lorch et al are leaving themselves a bit of capacity to account for these situations.
The fact is we don't know how it is being done and to say that it can't be done because of voltage drop on the supply side is just plain wrong.
rtbcomp
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I'm assuming nothing of the sort and neither am I saying it can't be done. All I'm trying to do explain what I reckon happens if you don't use a suitable extension lead, ie
MattH
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OK. If you plug it in with a Pussy Cat it wont work either.
MattH
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Weeeeellllllll...
While that part of the statement isn't exactly false, it's not strictly true either...
An inverter welder is in essence a switch mode type power supply, and the tolerance of variable voltage input is entirely dependent on the design.
I remember computer PSUs that had a voltage selector on the back, where you had to select either 220v or 240v and if you put it in the wrong place it'd drastically shorten it's life and/or occasionally cause output faults.
Simply rectifying the input to DC doesn't guarantee any resilience to a fluctuating/high/low voltage input at all. Because it's smoothed straight away it can tolerate a limited dip or surge for a few cycles with no ill effect but if you feed it 20% under spec it'll either refuse to work or possibly fail.
What makes the difference is the next stage and how that DC is subsequently handled.
One way is to actively monitor the input and adjust the modulation to suit - but this would have the possible implication of increasing the current draw to try and maintain the voltages which would lead to the 'runaway' of 'volts drop, increase current, volts drop more, increase current more, volts drop more, increase curr...boom'.
The other way would be to regulate the DC part of the supply down to whatever is considered a suitable expectation. Say you decide a 25% drop might happen, if you choose to regulate it down to 70% of the input it'll happily cope with it and not have any requirement to drag more current through - until the voltage drops below that expectation.
Yet another way (that can more efficiently cope with wider voltage variations) is to have an 'automatic' version of the old fashioned voltage switch above - so you handle the incoming voltage slightly differently in stages/groups/bands/whatever.
Those aren't the only ways to do it, but it might show that there are ways to allow a machine to run on theoretically undersized extension leads that would never work based on conventional wisdom or transformer machines.
Oh, and battery machines may well have the capability to operate in a 'UPS' fashion (mentioned in a previous post - output always run off battery, irrespective of whether mains is present).
Oops, textwall, sorry
I agree with everything you have said.
Just didn't want to be pointlessly longwinded about it
Jim Davey
R H Davey Welding Supplies Ltd
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