Portable Generators

[CaptainConduit]

If you were given a choice to purchase a portable generator that you were wanting to use in both a stand alone application (power tools etc.) or foe backup application for your home. Would you choose a floating neutral genset or a non floating neutral genset? Why?

 

[suemarkp]

Floating because most household transfer switches don't switch the neutral. I don't care about grounding for portable tool use, and frankly I think it is safer without being bonded to earth. If you really want to bond it, adding a bonding jumper is easy (just make a "bonding plug" with a wire from neutral to ground). Removing a solid bonding that was not intended to be removed can be difficult.

 

[don_resqcapt19]

It is my opinion that the use of a portable generator for cord and plug connected 120 volt loads is a violation of 250.20. Such a system is required to be a grounded system and you can't have a grounded system if the neutral is floated. Yes I am aware that a number of portable generators intended for use with cord and plug connected equipment as sold with the neutral floated. It is my opinion that such a generator cannot be used to supply premises wiring. Based on the Article 100 definition of premises wiring, it is my opinion that the cord between the generator and the load is premises wiring.
Don

 

[CaptainConduit]

How would you make a bonding plug? Would you then need to use GFCI protection in the stand alone application?

 

[suemarkp]

Buy a replacement plug. Put a #10 between the neutral terminal and the grounding terminal. System is bonded while that is installed. If all you have are GFCI receptacles on the generator, this bonding plug may pop the GFCI's and is not really in the right place, so you need to use a non-GFCI receptacle or find an internal point in the wiring compartment to do this bonding.

GFCI's will aid safety of a generator, grounded or not. But if it isn't grounded, it would be rare to get a leakage path or shock that will trip a GFCI. If the generator frame made a good enough ground electrode and you have a N-G bond, then perhaps GFCI's would help. Nothing is going to save you if you get between the neutral and hot of the same branch circuit.