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William K.
User Rank
Platinum
Re: Circuit breaker?
William K.   6/14/2013 5:43:12 PM
NO RATINGS
Why in the world would a garage door beome electrified just because the grounding circuit on the opener failed??? Only if there was an unintended short circuit in the opener would that happen. Failure of a safety system does not intrinsicly cause a dangerous situation, it only allows it to potentially happen. Most of the time the failure of the intentional (frame) ground does not lead to any problems at all, since most equipment and appliances seldom develop short circuits to the frame. On rare occasions such faults do happen, and in those instances a properly functioning frame ground will prevent a shock hazard from developing. So it would be a public service to avoid spewing misinformation about the degree of hazard arising from the failure of a safety system. While the failure of the frame ground could allow an unsafe condition to develop, it does not automatically create a dangerous situation with an actual danger present. 

William K.
User Rank
Platinum
Re: Shocking indeed, and plastic control panels
William K.   6/14/2013 5:33:05 PM
NO RATINGS
There are a few plastics that would serve quite well as a front-mounted control panel on an electric cook-top. They are some of the more expensive thermoset plastics, not the cheap thermoplastcs preferred by so many maufacturers. Thermosets are at a disadvantage in that unusable parts can't be simply reground and re-melted. But they can have much higher heat-deformation temperatures and they can be stronger, with better electrical properties and reduced moisture absorbtion. But those benefits are ignored by those companies that choose to provide much less quality along with many more features.

Jim_E
User Rank
Platinum
Re: Garage Door Opener
Jim_E   6/14/2013 3:20:59 PM
NO RATINGS
I was wondering why my garage door opener (house built in 2005) has a GFCI on the garage door opener.  Now I know!

 

Rob Spiegel
User Rank
Blogger
Re: Shocking indeed
Rob Spiegel   6/14/2013 1:06:21 PM
NO RATINGS
Thanks Kenkish. I'm surprised we haven't seen this one in our flow of Monkeys. 

kenish
User Rank
Platinum
Re: Shocking indeed
kenish   6/14/2013 12:14:27 PM
NO RATINGS
I was shopping for a new, higher-end range and the saleswoman in a big box store was surprisingly savvy and helpful.  She steered me away from Jenn-Air, and showed me why (they carried the brand).  The front-mounted control panel was semi-rigid plastic.  The first time boiling water or hot grease spills on the panel, guess what happens?  I purchased a similar range from GE with a glass touch panel.   Hopefully Jenn-Air has corrected this.  The engineer or accountant who chose plastic must never have used a cooktop!

kenish
User Rank
Platinum
Re: Circuit breaker?
kenish   6/14/2013 12:06:45 PM
NO RATINGS
Not only the 110VAC fan, but also any 110VAC light bulbs in the range!  Adding to your comment, there is some confusion in several other posts between a circuit breaker and a GFCI.  A CB protects against overcurrent but not ground faults while a GFCI is exactly the opposite.  A line protected only by a CB will still do a great job electrocuting someone unless there is a GFCI as well.

Total tangent...a new part of the Electrical Code requires garage door opener outlets to be GFCI protected.  If the neutral goes open, the garage door opener, rail, and the entire door (if it's metal) will be energized.  There's been a handful of electocutions when people touched a "hot" door.

OLD_CURMUDGEON
User Rank
Platinum
Re: Circuit breaker?
OLD_CURMUDGEON   6/14/2013 8:21:55 AM
NO RATINGS
  I think in the discussion above there is one point that is being misinterpreted.  I'm almost sure that the author's reference to the circuit breaker was the 2-pole breaker in his main distribution panel.

  Furthermore, historically for electric ranges w/ knob-control, when the burners are on low heat settings they are powered at the 120v level.

  Also, please be aware that up until a recent NEC (NATIONAL ELECTRIC CODE) code change, it was permissible in standard one & two family dwellings to use the either #8 or #6 2-wire /w GND for connection of the range.  The exact wire size was determined by the total ampacity of the range.  The code discusses this as 10KW above & below.  This allowable connection also existed for electric clothes dryers.  They were typically fed from a #10 2-wire w/GND cable (ROMEX, BX, etc.)  The one exception to this code rule was for mobil homes.  For both the cook range AND the clothes dryer, they required a different connection.  In both cases, the cables had to be a "3-wire w/GND" cable.  When the connections to the supplies were made with attachment cordsets & receptacles, there are NEMA designations for each configuration.  The latest NEC rules however dictate that electric ranges AND clothes dryers be connected with the appropriate "4-prong" cordsets, IF NOT directly wired to the feed cable, since both appliances are considered to be permanently placed.  The point is that the previous code revisions allowed the NEUTRAL AND the (green or YELLOW/GREEN) conductor to be the SAME physical piece of wire.  Now, however, with the recent change, the circuiting must be done so that the NEUTRAL conductor and the GROUNDING counductor ARE two separate physical pieces of wire.  One final note regarding conductors..... the NEC provides definitions for these conductors.  The NEUTRAL conductor is the "IDENTIFIED" conductor in cordage, and it is the GROUNDED conductor in such electrical distribution systems.  The GREEN, YELLOW/GREEN or BARE conductor is the GROUNDING conductor, normally carrying NO current, in position simply as a "safety" conductor. 

 

Rob Spiegel
User Rank
Blogger
Re: Shocking indeed
Rob Spiegel   6/14/2013 12:43:44 AM
NO RATINGS
Are companies blind to it, Chuck? We're getting tons of examples. It seems industry wide.

Charles Murray
User Rank
Blogger
Re: Shocking indeed
Charles Murray   6/13/2013 7:39:32 PM
NO RATINGS
That's unfortunately true, Rob. If I look back at my mother's old gas range, made by a company called Chambers, reliability problems were virtually non-existent. The same cannot be said, however, for today's electronics-laden appliances.

Leigh
User Rank
Silver
Induction
Leigh   6/13/2013 6:53:23 PM
NO RATINGS
Our latest kitchen has induction.

I'm not sure how popular induction cooking is in the USA, but essentially you get a flat glass top with capacative controls.

The power and control of induction is streets ahead of thermal elements or gas cooktops.

Advantages: Fast heating (can be cooking eggs in <15secs). Excellent Control. Super easy to clean. Cook surface remains cool. Energy efficient. No chance of electric shock!

Disadvantages: Glass top can be cracked or scratched (which is why we use silicone pads under cookware). Your cookware needs to be induction compatable.

 

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