Mobile DC Welding Machines

[junmal]

Anybody familiar with this machine which is powered by a diesel engine generator and produce DC output in the range of 400 amps to 500 amps and manufactured by Miller and Lincoln Electric. My question: is there a need to ground or earth this unit as what is being done here in our construction site. An earthing cable is bonded to the body of the machine and the other end is connected to a 3/4" diam earth rod and embedded on the ground. Length of the rod is about 2 feet. These units also has an 230 volt ac outlet source for small electric power tools. And with this an 30 mA RCCB was fitted as ground fault protection. If no earthing needed, why not?? Thanks for any response provided.

 

[roydm]

I don't recall having to ground these however it makes perfect sense from a safety point of view. Without the utility outlet you wouldn't need it.
Adding the ground fault protection is a good safety measure without that you run the risk of electrocution especially with multiple grounded metal tools.

Roy

 

[ScottyUK]

If you are using the 230V outlet then you must earth the machine. Rubber tyres won't pass 30mA to allow the RCD to disconnect the source in the event of an earth fault.


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If we learn from our mistakes I'm getting a great education!

 

[itsmoked]

Great point Scotty.

Keith Cress
kcress -

http://www.flaminsystems.com