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Is grounding obsolete?
GFCI receptacles are now allowed in some area's for replacement of old parallel blade receptacles. As these are usually fed by ungrounded cable.
If GFCI recepts. were to be made manditory for all outlets, then grounded cable would be unnecessary. Is this possible in the future? |
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And besides, if the GFCI fails in the closed position, then a ground would certainly be helpful. No, there is just no substitute for a real ground. GFCIs are a last ditch effort to keep people safe. |
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Honestly, the old nongrounding receptacles are fine for 90% of the house. Practically every lamp, TV, and appliance has only a 2 wire cord anyway. I personally feel much safer with proper grounding than betting my life on a GFCI tripping. |
Well, I suppose that if someday we only use non-conductive plastics to make our machines with, and no exposed metal parts, and our equipment doesn't require a ground for some kind of signal reference, then maybe all we would need is a 2-wire circuit. Seems to me though that metal will always have some use in our machines, at least for the foreseeable future, so grounding is essential.
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I can't imaging an all-plastic washing machine. Dryer? Forget it.
3-wire systems are here to stay. I don't even like the fact that most power tools have only 2 wire. I guess I'm an old fashioned fart. I prefer the safety of the 3rd wire. I suppose that in Europe, where I understand they use a 220V system which is not referenced to Earth (through a CT on the transformer), no 3rd wire is necessry, since no current would ever flow to Earth in such a system. |
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No, if you look at 250.114, These cord and plug items require a grounding conductor, and a GFCI cannot be used in lieu of that. 250.114 Equipment Connected by Cord and Plug Under any of the conditions described in 250.114(1) through (4), exposed non–currentcarrying metal parts of cord-and-plug-connected equipment likely to become energized shall be grounded. Exception: Listed tools, listed appliances, and listed equipment covered in 250.114(2) through (4) shall not be required to be grounded where protected by a system of double insulation or its equivalent. Double insulated equipment shall be distinctively marked. The exception to 250.114 recognizes listed double-insulated appliances, motoroperated hand-held tools, stationary and fixed motor-operated tools, and light industrial motor-operated tools as not requiring equipment grounding connections. (1) In hazardous (classified) locations (see Articles 500 through 517) (2) Where operated at over 150 volts to ground Exception No. 1: Motors, where guarded, shall not be required to be grounded. Exception No. 2: Metal frames of electrically heated appliances, exempted by special permission, shall not be required to be grounded, in which case the frames shall be permanently and effectively insulated from ground. (3) In residential occupancies: g. Tools likely to be used in wet or conductive locationsa. Refrigerators, freezers, and air conditioners b. Clothes-washing, clothes-drying, dish-washing machines; kitchen waste disposers; information technology equipment; sump pumps and electrical aquarium equipment c. Hand-held motor-operated tools, stationary and fixed motor-operated tools, light industrial motor-operated tools d. Motor-operated appliances of the following types: hedge clippers, lawn mowers, snow blowers, and wet scrubbers e. Portable handlamps (4) In other than residential occupancies: a. Refrigerators, freezers, and air conditioners b. Clothes-washing, clothes-drying, dish-washing machines; information technology equipment; sump pumps and electrical aquarium equipment c. Hand-held motor-operated tools, stationary and fixed motor-operated tools, light industrial motor-operated tools d. Motor-operated appliances of the following types: hedge clippers, lawn mowers, snow blowers, and wet scrubbers e. Portable handlamps f. Cord-and-plug-connected appliances used in damp or wet locations or by persons standing on the ground or on metal floors or working inside of metal tanks or boilers |
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There is no reason to worry about your drill being ungrounded because it's Class 2 double insulated. Pretty much everything these days is Class 1 (grounded), Class 2 (double insulated), or Class 3 (low voltage wall wart transformer). Class 0 ungrounded is about a hair away from being banned world wide, and really only still exists for very limited things like table lamps. |
Realize as well that AC line filters, which are common on things like switch mode power supplies and variable frequency drives, intentionally "leak" current to ground. Take away the ground and the filter won't work as well. And I think the future holds a lot more SMPS and VFDs too.
And as InPhase said above, GFCIs can malfunction too. Several years ago I got bit by a tile saw. I later punched the test button on the GFCI it was plugged into. Nothing. Apparently they all say "Test Monthly" for a reason. (Although I do understand that more recently made devices are supposed to be much better in this regard.) |
Everybody is of the opinion that grounding is important at this time.
With GFCI recepts, ground protection is necessary, as a means of tripping the circuit breaker! However, if AFCI breakers were used, then this would negate the necessity of the ground. Grounding may increase the cost of wiring by as much as 25%, think of the savings to be had in this regard. |
I suspect as GFCI/AFCI is required in more areas, SMPS makers will have to tighten up their ground leakage. It is possible to do active filtering without leaking as much to ground. Also they can use better Class X/Y caps that don't leak as much.
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