On Sunday 27 December 2015 17:07:15 John Thornton wrote: > I've built a bunch of automation machines for Briggs and Stratton and > they never pull a neutral only 3 240v hots and a ground. We always > have a control transformer for the 120v stuff... I have the same here > now. > That would also work as long as the machine frames are grounded, and a control transformer is used for the 120 volt loads. But my curiosity is aroused so I'll drag my copy of the NEC down & read a while. Later.
> On 12/27/2015 3:52 PM, Gene Heskett wrote: > > On Sunday 27 December 2015 16:17:20 John Thornton wrote: > >> well there is no neutral because it's a 240vac circuit only... > > > > The only reason there is not a neutral is that the wire was never > > pulled. And I am not sure that missing neutral is NEC kosher. My > > copy is now 17 years old, so I think I'd check a newer one to be > > sure. With it, you wouldn't need the stepdown and isolation tranny > > because you would then have a pair of 120 circuits available in the > > machine. But those loads MUST return on the neutral, they cannot > > use the static ground. > > > >> On 12/27/2015 12:16 PM, Bruce Layne wrote: > >>> On 12/26/2015 06:51 PM, John Thornton wrote: > >>>> There is no neutral in the machine, only L1 L2 and GND. The > >>>> Neutral for the house is bonded to ground at the panels. > >>> > >>> Electrician's Joke: > >>> > >>> Q: What's the difference between neutral and ground? > >>> A: About six inches. > >>> > >>> There's a very good reason the return current is carried on the > >>> neutral and the ground should not carry any current in normal > >>> circumstances, but we do need to understand that electrons don't > >>> care about our conventions. They're just as happy returning via > >>> the ground wire. They don't know that the green wire is off > >>> limits for all but emergency traffic. > >>> > >>> The concept of ground/neutral functional equivalence is also a > >>> real life saver for anyone who might otherwise consider standing > >>> barefoot on a basement floor while hot wiring any line powered AC > >>> circuit. > > > > Cheers, Gene Heskett > > ---------------------------------------------------------------------- >-------- _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
