Workshop Bench with electrical supply??

[colinh]

Hi there,

I have got so sick of working on the floor I have decided to make myself a bench. I was thinking of adding a couple of sockets to the bench so the whole thing will be earthed. Would this have any implications when welding on it (all metal construction).

Cheers
Colin

 

[madkayaker]

No. The "earth" on the welder is isolated from mains earth

 

[brightspark]

No. The "earth" on the welder is isolated from mains earth

its actualy called a return not an earth

 

[colinh]

Brilliant, hopefully by the end of next weekend I will be up off the floor!!

Cheers
Colin

 

[madkayaker]

Just make sure you have a decent earth to the bench from the mains incase an electrical fault turns the bench live! I have in the past run a separate 4mm cpc to benches with sockets on them just in case from earthed point such as building frame work (earthed to mains with min 10mm to comply with bonding regulations)

 

[500e]

Fix sockets under front of bench with shallow shelf to slot electric tools in, even better if shelf is mesh so no sparks can sit & burn cables.
Nothing worse than sockets at back if bench , leaning across to turn on\off cables cluttering work space.

 

[GrahamGKD]

I had some trouble with this when I fitted electrical sockets under my bench. When you weld on the bench your weld return and the mains supply earth will be connected and I did once get a disconcerting flash off the casing of one of my welding sets (via it's mains earth). This happened when feeding wire.

Whether right or not (I am not a sparky) I got around my problem by using properly earthed metalclad sockets mounted to a plate under the bench and isolating the socket mounting plate from the bench itself using some isolating washers.

 

[lshigham]

I had some trouble with this when I fitted electrical sockets under my bench. When you weld on the bench your weld return and the mains supply earth will be connected and I did once get a disconcerting flash off the casing of one of my welding sets (via it's mains earth). This happened when feeding wire.

Whether right or not (I am not a sparky) I got around my problem by using properly earthed metalclad sockets mounted to a plate under the bench and isolating the socket mounting plate from the bench itself using some isolating washers.

Something a bit dodgy is going on there, the welding ''earth'' (it's not really an earth, just the negative/positive connection depending on configuration) and the mains earth are entirely seperate, they aren't connected at all.

 

[madkayaker]

Sounds more like a difference in potential between the bench and case due to one not being bonded correctly. It's not uncommon for the "earth" on the case being poorly connected in factory or hole being powder coated etc.

 

[GrahamGKD]

Something a bit dodgy is going on there, the welding ''earth'' (it's not really an earth, just the negative/positive connection depending on configuration) and the mains earth are entirely seperate, they aren't connected at all.

Yes, I understand that part, but if you are welding a lump of metal on the bench and you put your welding return onto it then you are connecting the two aren't you? The work is on the bench (so making a welding return connection to the metal bench) and the bench is bonded to the mains earth.

 

[MattF]

That you don't want to do. Your bench shouldn't be grounded to the mains earth connection too. Make sure your sockets are well isolated from the bench and you don't need to ground strap it.