boc 200c tripping rcd

[minimog]

hi just got a second hand boc 200c mig it welds great but every now and then it trips the 35amp rcd (ive never had it do this with my cebora tig star or a 180a weco inverter set) i can do a couple of welds then all of a suden pull the triger and it trips i reset the breaker and its fine
im running 45 amp supply with a 35a rcd to a 32a blue plug
any one has any idea why
thanks
tristan

 

[rtbcomp]

Welcome to the forum.

Do you mean RCD (Earth fault trip) or MCB (Overload trip)?

 

[madkayaker]

for starters can you clarify if you mean RCD or MCB? however 35A isn't a size i would expect either to be! also a 32A socket must be protected by a 32A circuit protective device not a 45A.

RCD tripping is not unheard of with welding equipent as they can be quite a high leakage current to earth as there a big transformer.

 

[minimog]

thank you for the welcome

i have a 45 incoming supply for my unit then i have two fuse distribution board (one 10a for the lights and a 35a for the sockets) both these have rcd pluged into them(persume they are earth fault trip)







sorry its a 30a (ge minitrip)

 

[madkayaker]

sound like the welder is to big for the wireing but as you only have a 45A incomer there is not alot of spare capacity to do any thing with it without tripping out further up the system. would be best to get a decent spark in to have a look with the view of maybe changing circuit protective devise type or caracteristic but without seeing the job very difficult to give a defenitve safe answer

 

[minimog]

no probs just wondering if there was a prob with the welder like i said its never blown with the other welders ive pluged into it
cebora tigstar ac/dc tig set or my weco inverter mig set at full power

 

[madkayaker]

some welders do seam to pop breakers easier than others but there a inductive load so the start up currents can be very high. I have the same problem with a site transformer its got a 10A fuse in it but will frequently pop a 32A beaker. i also have a 6.5kva one that has a 30A fuse and it has never tripped a 32A braker

 

[minimog]

so if i try a fuse in (they left the original fuses)when the breakers was fitted and see if that stops the problem

 

[madkayaker]

could well do. even better if it was a real fuse instead of fuse wire.

 

[GrahamGKD]

Would a 'C' curve MCB be worth a try Madkayaker?

 

[madkayaker]

if its what i think it is you can only get a B type. i think its a plug in mcb. a BS88 fue is the ideal solution as there equvalant to a D type but will give disconection at a lower falut current than a D type. fuse wire would stand the inrush better but disconection can be an issuess on older systems and there is a real risk of people useing thicker wire!


once want to a house where the lighting was wired in 1mm equivalent (old imperial stranded stuff) and the home owner had got fed up with it blowing after he had fitted 20 haligon lights in kitchen so had used 2.5mm wirefor the fuse. anyone spot the issues?

 

[brightspark]

if its what i think it is you can only get a B type. i think its a plug in mcb. a BS88 fue is the ideal solution as there equvalant to a D type but will give disconection at a lower falut current than a D type. fuse wire would stand the inrush better but disconection can be an issuess on older systems and there is a real risk of people useing thicker wire!


once want to a house where the lighting was wired in 1mm equivalent (old imperial stranded stuff) and the home owner had got fed up with it blowing after he had fitted 20 haligon lights in kitchen so had used 2.5mm wirefor the fuse. anyone spot the issues?

the imperial was called 3/o29 now 1.omm ive seen a lighting circuit on a callout with 16 amp fuse wire wrapped round fuse holder 4 times the guy wired a new light up on end of the circuit wrong and turned on . it melted the full circuit back to the mains blew the fusebox up and knocked the boards cutout fuse out he said have i done much damage i said noooo just about 500 quids worth

 

[madkayaker]

i would have charged more than £500. board will have wanted £120 for them to replace the £3.50 fuse

 

[brightspark]

i would have charged more than £500. board will have wanted £120 for them to replace the £3.50 fuse

50 quid round our way 15 quid if i do it cos i keep the cutout fuses and i got the seals of ebay i just do the callouts some other poor b//er has to go rewire it after i put report in

 

[madkayaker]

when we all get nice new smart meters you wont be able to pull the fuse as it will send an alarm signal. there is a proposal of allowing sparks to register to pull the fuse but the board are not giveing in!

 

[minimog]

thanks for the replys ive refitted the original 30a fuse and its been fine no probs with tripping