Quick Electrial Question

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"Those of you who think you know it all, are very annoying those who do."

You know not that of which you speak.
There *is* energy in the magnetic field surrounding the inductor. Just _where_ do you think that energy came from?
When power was applied some electricity went _into+ the device that did _NOT_ come out as electricity *at*that*time*.
Similarly, when power is removed, some electricity comes out _after_ the switch is opened. Just _where_ do you think that energy comes from?
hint, it is *stored* in the electromagnetic field.

*snicker* Just where do you think the 'back emf' comes from when power is suddenly removed from an inductor?

'Male bovine excrement' applies. You even stated one situation you call 'impossible'. To wit: 'A changing voltage through an inductor, may create a phase-lagged current.' If you measure the *instantaneous* current _before_ and after the 'phase-shifting' device You *will* see different values. Draw a sine-wave, measure the instantaneous (not 'peak', or 'mean) amplitude at any given point during full cycle. Now measure the instantaneous amplitude at a slightly different phase of the waveform. Unless the two points you chose are symmetric around a maxima or minima of the waveform the *INSTANTANEOUS* amplitude _will_ be different.

And a *transient* phase-shift within a device _can_ cause a sufficient 'instantaneous' current difference (measured on opposite sides of the phase-shift) to trip an old-style GFCI.
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Robert Bonomi wrote:

Eric, Doesn't it just warm your heart to see people take a thread and make it their own! Reminds me of a guy I knew who was outstanding in his field. ; )
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On 9/6/2011 11:59 PM, Bill wrote:

Of the two, Robert is the only one who should have warmed yours.
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Swingman wrote:

Yes, I would like to make it clear that his was the only reply I was referring to (since it seemed like rant).
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"Bill" wrote in message Eric, Doesn't it just warm your heart to see people take a thread and make it their own! Reminds me of a guy I knew who was outstanding in his field. ; )
==============Must have been a farmer!
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On 9/7/2011 12:59 AM, Bill wrote:

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On 9/4/2011 8:09 AM, Dave wrote:

motors will often trip GFCI's that is why they should never be used on refrigerators, disposals, diswashers and sump pumps and the like.
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Steve Barker
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I know of complete factories that are GFCI protected and most high voltage protection systems that include 87 (IEEE) GFI protection.
They can and should be used but will find defective wiring.
-------------------- "Steve Barker" wrote in message
motors will often trip GFCI's that is why they should never be used on refrigerators, disposals, diswashers and sump pumps and the like.
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Steve Barker
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Well you are absolutely wrong.
New code requires that the sump pump be plugged into a gfi. So What do you say to that... Any basement circuit requires it.
I had an inspection recently and they were trying to ding me on that, but my inspection was not related to that. And I argued, that when the house was built that was what was called for.
On 9/4/2011 11:44 PM, Steve Barker wrote:

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On 9/5/2011 9:25 PM, tiredofspam wrote:

I am not wrong in saying they should not be used on motors. It's been proven that motors can cause false trips on gfci's.
Plus, very few AHJ's are on the "new" code. And _I_ for one will never put a sump pump on a gfci. Code or not. And I'm not gonna look it up, but i think you're wrong.
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On 9/5/2011 10:25 PM, tiredofspam wrote:

Only if it's in an unfinished basement (or unfinished portion of a basement), or a crawl space. And that's not new, either: that provision dates from the 2008 Code, maybe earlier.

I say, you're mistaken.

Not true.
GFCI protection is required *only* in unfinished basements and unfinished portions of partially finished basements:
"...receptacles ... in the locations specified ... shall have ground-fault protection ... Unfinished basements -- for purposes of this section, unfinished basements are defined as portions or areas of the basement not intended as habitable rooms and limited to storage areas, work rooms, and the like ..." [2011 NEC, Article 210.8(A)(5)]

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Again, tell that to my local inspector. GFCI's were required in my finished basement. Every outlet had to be on a protected ckt.
On 9/6/2011 6:51 AM, Doug Miller wrote:

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On 9/6/2011 10:34 PM, tiredofspam wrote:

One of two things, then: either you live in a jurisdiction that has adopted more stringent rules than those specified by the NEC, or your local inspector doesn't know or doesn't understand the NEC.
The NEC is only a model, a suggestion. In and of itself, it has no force at all; it acquires the force of law *only* when it is adopted as the governing regulation by state law or municipal ordinance -- and such jurisdictions are free to adopt it in toto, or in part, or with such exceptions or additions as they see fit. It's entirely possible that your jurisdiction has done exactly that. That's not unheard of, you know: the Chicago electrical code, as I understand it, is *based* on the NEC, but has numerous additions (e.g. all wiring must be run in conduit, no Romex allowed) that appear to stem as much from a desire to keep union electricians employed as from an understandably morbid fear of widespread fires.
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On Tue, 06 Sep 2011 22:46:05 -0400, Doug Miller

...or is making up his own rules as he goes along. BTDT.
<...>
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On 9/6/2011 11:44 PM, snipped-for-privacy@att.bizzzzzzzzzzzz wrote:

Well, I was trying to be nice... but yeah, that can happen too. Still (IMHO) falls into the category of "doesn't know or doesn't understand the NEC", though.
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On Wed, 07 Sep 2011 14:05:23 -0400, Doug Miller

I had an inspector (not electrical) that knew the code, and even told me what the code was, "but I want you to do it this way...". I didn't want to piss off the inspector, so...
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On 9/6/2011 10:44 PM, snipped-for-privacy@att.bizzzzzzzzzzzz wrote:

this is the most likely option . And he needs to be challenged. There IS an appeals process and a committee.
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wrote:

...and, of course, retaliation. He was eventually fired for incompetence (he failed the exam three times before that, though).
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[ sneck ]

Chicago Electrical code bears only a vague resemblance to the NEC. Most jurisdictions cite a particular year of the NEC (or of the BOMA -- Building Owners and Managers Association -- code, which incorporates by reference the NFPA -- National Fire Prevention Association -- code, which incorporates the NEC by reference) as 'base', and then add any additional jurisdiction- specific rules.
The Chicago building code specifications for electric wiring does *NOT* do that. Everything is specified directly in the local code. And the code itself is a 'swamp'. I once had a 'difference of opinion' with a building inspector over an electrical issue, and we spent a good five minutes citing code 'exceptions' back and forth at each other. Chicago code does -not- say 'this section rules _unless_ the exception in xyz applies', it says "if this condition is met, then section xyx does not apply". Chasing the applicable exceptions to a given section is a challenge. And the section that contains an exception to the base-line rule, may itself be subject to an 'exception' in a far-removed section of the code. "lather, rinse, repeat" applies.
I eventually prevailed over the electrical inspector, having reverse- engineered the code one step further than the inspector had. And he 'went away unhappy', having _not_ collected a payoff over the purported 'code violation'.
Chicago electrical code allows some things that are forbidden by NEC, and forbids other things that are allowed by the NEC. There is a fair amount of 'coincidental' overlap on the basics, but a *lot* of difference in the 'details'.
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Yup! Here come's the old "I wasn't there but this is what really happened" and "I know more than your Inspector does"
Maybe Dougy has learned something about not telling **you** what happened **to you** from the other side of the world.
Funniest yet... Dougy has professed to the world, repeatedly, he has filtered me and has his mouth gagged, for once. Stamping his feet as he bangs his head against the wall, pacing, trying not to burst a #14cu in his head.
Hook, line, and GFI.
--------- "tiredofspam" wrote in message
Again, tell that to my local inspector. GFCI's were required in my finished basement. Every outlet had to be on a protected ckt.
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