ESAB DTB 250

[GavJ]

Hi All, its getting about time to change my wee Migtig inverter for something more substantial. Been looking at one of these ESAB machines and it says it can be run on a single phase supply. I assume a 3 pin domestic plug wont cope? Whats my options? Im pretty sure the consumer unit in my workshop can cope with a 16 amp round plug, not so sure aboout the wire from the house to the workshop though? Whats sort of draw can I expect, I normally have my inverter set at a about 100 amp for general work (200 amp machine)
ta
Gavin

 

[tigdlo]

The manual isn't totally clear but it looks like it needs a 50A fast blow fuse with 10mm2 cable or 63A slow blow fuse with 16mm2 cable with a primary current of 68A @ 230v, thats the cable from the wall not the one supplying your workshop. If you are ever going to use it at max current I would be concerned about the supply to the house not just the house to the workshop especially of the house is occupied while you would be welding.

You may get more responses opening a thread about running big transformer tig welders off a domestic supply.

 

[GavJ]

Thanks tigdlo, Im no spark but rhe current seems really high for a domestic supply... might be better with a small inverter....

 

[aesmith]

To put this in context the transformer feeding our house is only 64 amp. If you don't know what size cable you have from the house to workshop, a photo of the devices at each end might enable some educated guesses. Does the supply come from a breaker in the house consumer unit, or is it split off between the meter and the consumer unit with its own switch/fuse/breaker?

 

[GavJ]

The feed to the garage was installed before we bought the house, we have had a consumer unit fitted and when that was done I left a seperate breaker for the garage but the electrician couldnt find the feed. Its underneath a tiled kitchen floor somewhere and its connected to the sockets ring main...... At the garage end the wires are reasonably substantial, I would say they are larger than 2.5mm but not as large as 6.0mm.

 

[sg66]

Should be a simple enough process of removing fuse or tripping mcb's till you locate the feed that no knocks off the garage, if its spurred off a ring main I wouldn't be drawing more than 16amp

 

[GavJ]

Hi SG66, it is off the socket ring main which has a 32amp breeaker, this just feeds a small extension so largest load would be if missus plugs in the iron while Im in the garage. Other than that its only a TV and some lights.
The house was built by a private builder and has some unusual features.... the ring mains are wired with multi stranded oversized wires rather than normal twin & earth, no idea of their capacity but either way I agree that 16 amp should be my limit to be safe.

 

[AVI_8]

The feed to the garage was installed before we bought the house, we have had a consumer unit fitted and when that was done I left a seperate breaker for the garage but the electrician couldnt find the feed. Its underneath a tiled kitchen floor somewhere and its connected to the sockets ring main...... At the garage end the wires are reasonably substantial, I would say they are larger than 2.5mm but not as large as 6.0mm.

That would concern me not knowing where the power is coming from, do you have a solum under the house so that you can trace the supply to the garage.
You mentioned that the supply was more than 2.5 and less than 6mm which will probably be a 4 MM which has a current loading of 37 Amps clipped direct or 30 amps through a conduit from the tables I’m looking at and you’d need a 32 amp socket if you’re using the welder at full power, personally I’d want that running of its own dedicated breaker.
How far is your garage from the house and is it attached? Would there be easy access to run a 10mm SWA from the house to the garage consumer unit?

 

[aesmith]

If your garage supply is a spur off a 32A ring with no form of fuse or breaker between, then should be run with cable capable of carrying the full 32A. Current carrying capacity depends on installation method as well as cable size, but with that caveat 4mm2 cable should comply.

As I understand it, because the 16A and 32A commando plug/sockets don't have their own fuse, they should only be connected to a matching circuit and breaker. Meaning you shouldn't have a 16A socket on a 32A ring, as a fault could exceed the rating of the socket without tripping the breaker.

 

[GavJ]

Garage is about 10m away from house, I dont know if the wire is in coduit, it is as it appears through concrete floor in garage but may not be all the way to the house. Maybe in future I will run a new dedicated feed but means digging up tarmac driveway!!
There is only about 10" below flloor at this end of the house and the floor is partially tiled and partially laminate so would be a major undertaking to lift the boards.

 

[aesmith]

You refer to a consumer unit in the garage. If that's on the end of the 4mm cable then I'm pretty sure you'd be good to fit a 16A breaker for your welder socket. In Scotland this work wouldn't be notifiable, so although it needs to comply with wiring regulations you don't have to involve local authority Building Control.

 

[GavJ]

Thanks