Bought a big Arc Welder that blows fuses.

  1. johnna Member

    Hi everybody, first post!
    I've used the search function and have gathered a fair bit of info, which leaves me looking for a little confirmation before I engage someone to do the job.
    I have recently bought a powerful Arc welder form Germany. I have removed the Schuko plug and have replaced it with a 13amp fuse three pin item. The Welder fires up and will weld, but blows fuses and trips the fusebox for fun!
    I use the welder in my garage (built into the house) and the existing sockets in there are upon the downstairs ring. Even when the welder is turned right down, it trips the protectors out.
    Next to the red trip switch for the downstairs ring is a 'Spare' red trip switch upon my fuse board. All of this section is RCB protected. The house is only 12 years old by the way...
    Also, the wall the fuse box is upon backs onto the garage wall.

    So, is it feasible to have an electrician install a 32amp socket within the garage, with a short length of thick meaty supply cabling running through the wall to this spare 32amp trip switch in the fuse box?
    I'd be keen on doing a lot of prep myself, such as drilling the hole through for the wiring and even feeding the cable through it, so the electrician need only wire it up, inspect the job and record his satisfaction.

    Are my plans workable?

    Thanks in advance.

    The folks over at DiYNot have suggested that a 16amp welder should not trip the 13amp fuses or the 32amp downstairs ring, but all the advice here suggests it would.
    Please help!
     
  2. English Steve

    English Steve Senior Bumpkin

    Hi Johnna, and welcome.

    I am not an electrician, but you should be able to run a feed for your welder into the garage as you describe.
    Please would you post more detail about the welder, as I wouldn't have thought it should trip the main 32a breaker. Make, model, min/max currents would give other more knowledgeable people on here the opportunity to comment on your set-up.

    Regards

    Steve
     
  3. Wozzaaah

    Wozzaaah The wizard of woz Staff Member

    Messages:
    12,748
    Wiltshire, UK
    Hi John, first things first, welcome to the forum fella :hug:.
    You need to tell us a bit more about the machine, what make and model is it and what does the data plate say on the back regarding supply rquirements? If you're not sure how to understand all the figures on the data plate, post a pic of it and we'll explain it. You do say it's a big arc welder so it will probably need more than 13 amps and with a lot of protection devices, if the plug fuse blows it will trip the protector too.
     
  4. mishka

    mishka Is it me?

    Messages:
    250
    Cambridge, UK
    Hi,
    When you say:
    do you mean the RCCD protector? I would have thought the plug fuse would go before a current trip. If it is the RCCD then that's a BIG indication something is majorly wrong and is nothing to do with the load your welder may be putting on the socket.
     
  5. Wozzaaah

    Wozzaaah The wizard of woz Staff Member

    Messages:
    12,748
    Wiltshire, UK
    I suppose it could also be a faulty or over-twitchy rcd/rccb, we have one that trips as soon as a lighbulb blows. There's still a good reason why the plug fuse is blowing though, the fact that you can actually use it means that it's probably just that a 13A supply is not enough for it. Regarding a dedicated 32A supply, no problem at all with that, 32A should be ample for anything you use in there.
     
  6. mishka

    mishka Is it me?

    Messages:
    250
    Cambridge, UK
    A Schuko plug is only rated up to 16A, so its unlikely this welder needs anything more than that. If the welder is blowing fuses and trips even on the lowest setting that still indicates *something* is amiss.
     
  7. johnna Member

    Oh Knickers!
    Thanks for the replies fellas.
    I bought this arc welder:
    http://cgi.ebay.co.uk/ws/eBayISAPI....m=370031526048&ssPageName=STRK:MEWN:IT&ih=024

    Specs:
    Model Electric welder BESG250
    Mains supply 230 ~ 50 Hz
    Protection class IP21
    Input capacity 3.7 kW
    Fuse 16 A
    Welding current (90- 250 ) A
    Diameter of electrode (2.5- 4) mm
    Dimension 475 x 300 x 375 mm
    Net weight 22.0 kg
    Gross weight 23.6 kg


    Is that any help? I hope the welder isn't fubarred...
     
  8. johnna Member

    Now funnily enough we had problems with Irons that tripped out the system, but also when a bulb goes, the system trips out.
     
  9. johnna Member

    [​IMG]

    [​IMG]

    1-50/60hz

    u1 = 220v

    1Max = 68Amp

    1eff = 22.4Amp
     
  10. mishka

    mishka Is it me?

    Messages:
    250
    Cambridge, UK
    Might be worth buzzing it through with an insulation tester to check the insulation to the output terminals. If you have access to a PAT tester that would be better still - check with each output terminal as "earth". Any leakage there would upset an RCCB.

    I see Berlan are keen with their specmanship :)
     
  11. mishka

    mishka Is it me?

    Messages:
    250
    Cambridge, UK
    Or, it *might* just be the initial surge on striking an arc. Might be worth wiring it up to a spur on its own, with an MCB specified for high inrush currents, like a type D.
     
  12. johnna Member

    I imagine that there would be a bit of a surge with it.
     
  13. Wozzaaah

    Wozzaaah The wizard of woz Staff Member

    Messages:
    12,748
    Wiltshire, UK
    Hang on a mo, if i read that correctly the specs say 16A fuse but the data plate says 68A max and 22.4A eff? :confused:
     
  14. mishka

    mishka Is it me?

    Messages:
    250
    Cambridge, UK
    Yes ... hence my comment on the creative specmanship ;)
     
  15. johnna Member

    Please explain the implications of this to me...


    ...please!
     
  16. Drains

    Drains Yeah, nah.

    Messages:
    7,707
    Location:
    Sefton, South Island, NZ
    Er, John, it's a 250A MMA set, right? A 140A set will happily blow 13A fuses at full power, once it warms up, so I wouldn't expect yours to work too well on a little supply. You need a 63A supply to use it at full power, but do you need to run 5mm rods?

    You might be in trouble with this one as it only seems to go down to 90A, which means the smallest rod you can run on it will be a 2.5. Forget positional work except with bigger rods.
     
  17. johnna Member

    Aw knickers! I wasn't looking to run it on much above 3mm rods anyway with 2.6/2.5 being the most usual.

    Billix! Could I run it from a petrol/ diesel generator?
     
  18. Drains

    Drains Yeah, nah.

    Messages:
    7,707
    Location:
    Sefton, South Island, NZ
    Oops, sorry John, it says 70A. That's better. You'll be able to do plenty on 2.5's then.
     
  19. weldequip Forum Sponsor

    Messages:
    5,203
    Location:
    England
    You would normally be able to run thin rods (1.6 & 2.0mm) from an AC arc set before it started to pop fuses, but that's from a set with the more usual 40amps or so minimum setting. That fella is 70amps minimum which puts it into 2.5mm minimum rod size territory (as Si says). Try wiring it into a heavier supply (16 or 32amp electric cooker type) & if it's still popping fuses on minimum it's a return job ;)
    weldequip
     
  20. piman Member

    Messages:
    1,609
    Location:
    Oswestry Shropshire
    Hello Johnna,

    3.7Kw at 240 volts is nearly 20 amps at 0.8 (nominal) power factor.

    You do need to identify exactly what is tripping and what sort of device it is.

    There is a confusing range of circuit breakers now, rccd now normally called rcb which only sense out of balance current between live and neutral (basically if all the current out is not returning the breaker trips) and rcbo's which do that and also sense overcurrent. Basic circuit breakers also come in different types depending on the type of load supplied . Normal domestic breakers (Type B I think) are more sensitive to overcurrent than type C which are designed for inductive surge currents such as motors and transformers (as your welder is).

    From what you have posted I would say that a 13 amp plug and socket is too small. I think that a 32 amp supply is required, as the next lower size is 16 amp which I feel is also too small.

    Alec
     
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