Grounding of standalone portable equipment

[Shells]

This is probably a very basic question but grounding of portable air compressors, welding plants, lighting towers, temporary generators etc - is it really required? Based on NEC, as long as it is a separately derived system, grounding is not required, at least for portable and vehicle mounted generators. However, it seems like it may be required in some locations based on the local codes/AHJ etc. If the equipment is diesel powered then I am guessing you may want to for static electricity?



Any advice you can offer would be appreciated.

 

[petersonra]

This is probably a very basic question but grounding of portable air compressors, welding plants, lighting towers, temporary generators etc - is it really required? Based on NEC, as long as it is a separately derived system, grounding is not required, at least for portable and vehicle mounted generators. However, it seems like it may be required in some locations based on the local codes/AHJ etc. If the equipment is diesel powered then I am guessing you may want to for static electricity?



Any advice you can offer would be appreciated.

If by grounding you mean connecting to the earth via a grounding electrode system, my opinion is you gain almost nothing whether it's required or not so I wouldn't be all that worried about it for temporary equipment.

 

[Shells]

If by grounding you mean connecting to the earth via a grounding electrode system, my opinion is you gain almost nothing whether it's required or not so I wouldn't be all that worried about it for temporary equipment.

yes, referring to connection to earth via grounding electrode system. Thanks for the input

 

[petersonra]

yes, referring to connection to earth via grounding electrode system. Thanks for the input

Think about it. How many people using a portable gas powered welder would bother to pound two ground rods first to weld for 15 minutes then pull the ground rods out. It just isn't happening.

My opinion a portable gas-powered welder is a type of generator and thus if it's required for a regular generator an earth connection would be required for it. But there's just no real point in doing so.

 

[kwired]

When you connect said generator to a premises wiring system, the premises system should already have a GES, your ungrounded source becomes grounded when you connect to a premises system. Proper method is usually to run separate grounded and EGC conductors between the premises wiring and the source and have no bonding of the grounded conductor at the source.

 

[Fred B]

This is probably a very basic question but grounding of portable air compressors, welding plants, lighting towers, temporary generators etc - is it really required? Based on NEC, as long as it is a separately derived system, grounding is not required, at least for portable and vehicle mounted generators. However, it seems like it may be required in some locations based on the local codes/AHJ etc. If the equipment is diesel powered then I am guessing you may want to for static electricity?



Any advice you can offer would be appreciated.

Might want to look at 250.30 and 250.34 again. Exception has quite specific criteria.