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Rob Spiegel
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Re: Shocking indeed
Rob Spiegel   6/13/2013 4:05:16 PM
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Thanks GTOlover. One of the patterns I'm seeing is that they discard their older white box appliance that has worked great for 25 years -- all mechanical, no electronics -- in favor of a preferred color and the electronics whiz. And of course, the new one fails.

Rob Spiegel
User Rank
Blogger
Re: Shocking indeed
Rob Spiegel   6/13/2013 4:01:12 PM
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Yes, Chuck, and there are two patterns that match these quality problems time-wise: more electronics and outsourcing.

Rob Spiegel
User Rank
Blogger
Re: Shocking indeed
Rob Spiegel   6/13/2013 1:25:15 PM
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Hey Naperlou. JennAir left a comment here. I passed it on to Bernard and asked him to let us know how the conversation turned out.

jlawton
User Rank
Gold
Re: Circuit breaker?
jlawton   6/13/2013 1:07:50 PM
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That may be how it connects, that may be what it's sold for, that may be a useful circuit that protects reasonably well for a lot of purposes, but you just can't "prove" that the current that the circuit detects ACTUALLY flowed into a node (ground) the load isn't even connected to. Certainly it's a FAULT current detector, but I defy you to prove it's a GROUND fault current detector. Semantics maybe, but nonetheless the premise isn't really valid, I don't care how many connection schematics or usage manuals or any other diagrams or material you try to use to "prove" your assertion, sorry!

Rob Spiegel
User Rank
Blogger
Re: JennAir on the line
Rob Spiegel   6/13/2013 1:01:26 PM
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Hi Jordan, Nice to see you weigh in. I'll make sure Bernard gets your message.

JennAirUSA
User Rank
Iron

JennAirUSA   6/13/2013 12:55:35 PM
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Hi Bernard, my name is Jordan and I am a representative of JennAir. I am terribly sorry to learn of the experience you have had with your range and sincerely hope no one was hurt.  So we can look into this further review, please reach out to me via e-mail at JennAir.Digital@JennAir.com with ticket number 48193. Also, please include your name, your complete contact information with the model and serial number of your range. 

Ann R. Thryft
User Rank
Blogger
Re: Shocking indeed
Ann R. Thryft   6/13/2013 12:49:59 PM
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Battar, it's both. Before receiving UL or other such approval, usually there's an internal QA cycle so the product doesn't fail those external tests.

RPLaJeunesse
User Rank
Iron
Re: Circuit breaker?
RPLaJeunesse   6/13/2013 12:07:18 PM
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My point is that GFCIs are not for use just on unbalanced lines like you seem to believe. That may be true for 115VAC GFCIs, but not all GFCIs. For a 2-pole GFCI to work properly the load neutral need not even be connected (although the GFCI must have its neutral line connected). Perhaps this will help, from http://w3.usa.siemens.com/powerdistribution/us/en/product-portfolio/circuit-breakers/residential-circuit-breakers/gfci/pages/gfci.aspx?tabcardname=Wiring%20Diagram 

GFCI Wiring

jlawton
User Rank
Gold
Re: Circuit breaker?
jlawton   6/13/2013 11:39:48 AM
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I can't for the life of me understand what your problem is here. The "center tap" of the pole pig for the line phase serving this area is of course grounded. A "standard" GFCI uses a differential current transformer which typically services just one side of this transformer. The entire premise is to ensure that the exact amount of AC current that flows out of the "hot" leg is returned through the wiring provided for the return circuit, if instead it goes to ground through an alternate path that's a fault and upon detection the circuit would of course be opened. If you were to try to make this work on a circuit that's wired only across two hot legs, you only have the two legs to sense current on, NEITHER of them is "ground current" per se so there's no way to sense a fault to ground, all you could do is sense a "sneak path" to the opposite hot side of the transformer but what good is that? A GFCI doesn't have any "magical" abilities, it just senses current differences in order to detect problems that cause it to sense certain problems by working the way it's designed to work. I don't know how this got so far off topic anyway, from all we can tell there wasn't even a GFCI at the circuit level so in the case at hand there wasn't any protection at all, the worst possible case!

RPLaJeunesse
User Rank
Iron
Re: Circuit breaker?
RPLaJeunesse   6/13/2013 10:32:51 AM
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I would consider "the same" leakage from a balanced (with respect to ground) pair (e.g. 230V home power) would imply either two identical leakage impedances occurring simultaneously (highly unlikely) or a line-to-line bridge which, by its nature, is not a ground fault. Admittedly, bridging the lines could be quite deadly nonetheless, but may constitute a double fault (i.e. product design dependent). For a single point of influence to affect both lines of a balanced pair equally it would have to be at the center point of balance, which by nature is 0V and hence not a point of danger for causinng electric shock. Similarly having "the same" leakage from an unbalanced pair (e.g. 115V) to be a double fault condition, as there would need to be two simultaneous leakage paths of wildly different impedances, occurring at exactly the same time. Again, highly unlikely. 

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