On Sunday 27 December 2015 18:21:33 John Thornton wrote:

> The VFD filter has no place to connect a neutral... only hots and
> ground.
>
Goody.  But if it works, hey!

> On 12/27/2015 5:10 PM, Gene Heskett wrote:
> > 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.
> >
> > After an hours searching thru it, and its the 1996 issue, a 240 volt
> > single phase line w/o a neutral is legal if it goes only to that
> > machine AND the machine was designed for that power configuration,
> > eg is designed to run on 240 for everything.
> >
> > IOW if it goes anyplace else in the building besides that machine,
> > it has to have a neutral too.  And of coarse grounded is a given.
> >
> > So in your case, you can utilize a 240-120 stepdown that is NOT an
> > autoformer.  And from whats been said, that is what you are doing.
> >
> > However, speaking as a C.E.T., not having the neutral so that the
> > filters you are installing can ship their noise back up that
> > separate circuit, effectively isolated from what is supposed to be a
> > nice quiet ground, does seem like it would put a lot of the absorbed
> > noises into the grounding system. And unless putting the filters in
> > fixes it, making me just a worry wart, I believe this may be much of
> > your noise problem.
> >
> > Since we've come 19 years into the future since my copy of the NEC
> > was put to bed & sold, with more efficient (and more noise
> > sensitive) ways to do things now, I'd expect that a current copy of
> > the NEC would more than likely have some additions designed to head
> > off problems like this.
> >
> > Unfortunately a current copy is now at or somewhat north of a 120
> > dollar bill.
> >
> >> 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
> >>
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> >
> > Cheers, Gene Heskett
>
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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>

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