mcb advice

[Alex.]

Afternoon all
I went to use my welder today, first time after I'd run a new 2.5mm cable out to the garage. Sadly the mcb feeding the sockets tripped as soon as I tried to feed the wire to the torch! The welder is a SIP Handymig, and has always run OK from a 13A socket until I tried to 'improve' things. The rest of the supply is from a 32A MCB in the house CU through a 16A in a small CU in the garage. The garage CU wasn't there before so I feel that must be the problem but 16 being greater than 13 I don't see how...

 

[brightspark]

it will be a b type breaker and more sensitive than a 13 amp fuse. try changing it to a c type and it will handle the inrush current on start up failing that change to a 20 amp c type

 

[daleyd]

Can You the welder from a socket in the house just to discount the welder itself being the problem? Worth a try as a quick first test.

 

[dobbslc]

As above, the 13 amp fuse will take a fair bit of surge it pop it but a 16 amp b type mcb won't, just swap it for a c type mcb and you'll be ok.
Assuming the welder is ok...

 

[rikrobson]

How long is theatre. You could have a voltage drop just enough to trip the mcb.

 

[Alex.]

Thank you all. I put in a type C 16A mcb and the welder is back in action. Just got to improve the operator now.......