GFCI's in Laundry room

[Jae Williams]

Why are GFCIs sucha good thing to have? SAFETY—

How long does it take a GFCI to shut down a circuit?
0.025 seconds

How long does it take a breaker to shut down a circuit?
3 seconds

How long does it take electricity to shut down an adult heart?
0.2 seconds

The time required to trip a breaker (up to 3 seconds) could allow a high draw motor to start and allow the draw to diminish before tripping the breaker. This could possible be a safety hazard, but a breaker won't tell you. The GFCI will trip (>0.025 seconds) before the draw can get to a hazardous level.

[Michael W. Gault]

Originally Posted by jwilliams4

Why are GFCIs sucha good thing to have? SAFETY—

No argument to that....

The time required to trip a breaker (up to 3 seconds) could allow a high draw motor to start and allow the draw to diminish before tripping the breaker. This could possible be a safety hazard, but a breaker won't tell you. The GFCI will trip (>0.025 seconds) before the draw can get to a hazardous level.

Nor to that...

Jae,

Are you for GFCI's throughout the house?
Do you believe some motor starts trip GFCIs?
Are those trips 'nuisance trips' or should I recommend a new refrigerator if the current ones' compressor is beginning to 'pull' a tad on startup and a "6ma" fault is detected...

And where do I begin to explain water and lint or dust as a conductor to ground (to a client) when her disposer trips the new GFCI's they installed but never tripped the old non GFCI circuits...

[Jae Williams]

I was merely attempting to simplify Gregs post so that even I could understand it.

I don't think I would get so technical as to explain dust and water paths. However, I have frequently used the 3 second to .025 second story and the client can understand that, easily enough. Especially when I throw in the part about how quickly it can cause death.

GFCI trips so much faster than the average breaker, and that is easily understood.

[Jae Williams]

Originally Posted by mgault

Are you for GFCI's throughout the house?
Do you believe some motor starts trip GFCIs?

I don't necessarily recommend it, but it wouldn't be a bad idea, would it?

Motor starts?? Only if the motor is faulty somehow (i.e. loose wire in the windings, bad bearing causing "drag" on the shaft) and drawing an excessive amount of current.

[Patrick Bolliger]

OK let me throw this in the post..
What about two prong appliances into a GFCI? Current "draw" at moment of startup (motors) maybe one thing but fault current via another path in the appliance is another thing.

This is where the physics of current, resistance and voltage get confusing to many people. A simple way to put it in a black box perspective is :

Current (amps) flowing in a circuit ( your appliance/ load) better have the same current values flowing out of the circuit.. (Example: one amp in ,one amp out in ... a perfect world just for simple example) Appliance internal circuit with resistance= load.

Sooooo we have a situation where fault current takes another path ( lets say the case of the appliance)..the GFCI should trigger (pop) when the "difference" is "registered" within the GFCI.. Hot to neutral or Neutral to ground... Am I just mucking up the water here folks for everyone...

Now add arching... to your GFCI..What happens? well you have a situation where the resistance is dropping very fast and current is getting very high..
But wait current value in and current value out should be the same right?
Hmmm Are there ACFI and GFCI built into one device?
.. For example the wire is loose in a washing machine (Hot side comes into contact with neutral terminal .. The load has just changed to practical no resistance..super high current at that very instant. POW! ...at that instant tremendous current has just passed at that point! Hopefully your OCPD will trigger.... The resistance went to practically zero ( in a perfect world).. Does your GFCI trigger... Your better hope so maybe.. It is not a AFCI..

The small point of resistance in a circuit ( I mean inside appliance here) has the greatest effect on current flow . I =V/R

Sorry if I am babbling on here... Thread drift ....

[Jae Williams]

Not babble--well explained.

[Jae Williams]

"What about two prong appliances into a GFCI? Current "draw" at moment of startup (motors) maybe one thing but fault current via another path in the appliance is another thing."

About two pronged outlets--

http://www.cpsc.gov/cpscpub/pubs/524.html

[whandley]

Hey Russ,

Aren't you finding that just about everything in a newly constructed home is AFCI/GFCI protected? Bedrooms, hallways off the bedrooms, bathrooms, kitchens, laundry rooms, wet bars, sub areas, garages, exterior patios, etc.

Living and dining room type areas are about the only receptacles not protected. Look at all the smoke alarms required in new homes, one in each level of the structure, each sleeping area, each hall way leading to sleeping areas, each room with a change in ceiling elevation greater than 24" off the hall way leading to a sleeping area. There just about everywhere except the kitchen and bathrooms.

[Greg Fretwell]

I don't have a problem with GFCIs everywhere but if you are not near a conductive path they really don't accomplish much. If you are sitting in your easy chair a piece of equipment could energize you to 120v and you would never know it. Neither would the GFCI. It is when you are easily grounded that the GFCI is necessary.As for the fact that defective equipment trips a GFCI, I don't know what you tell the customer. What do you tell them when you point out the frayed extension cords and overloaded outlets?

[Russel Ray]

Originally Posted by whandley

Hey Russ,

Aren't you finding that just about everything in a newly constructed home is AFCI/GFCI protected? Bedrooms, hallways off the bedrooms, bathrooms, kitchens, laundry rooms, wet bars, sub areas, garages, exterior patios, etc.

No. Our AHJs down here finally approved AFCIs in October 2005, so they won't start showing up in my inspections regularly until, oh, around, October 2006 or so. The new construction that I've been inspecting was all started prior to October 2005, so they weren't required. Permits pulled after October 2005 will require them, and it seems to be taking 9-12 months to build houses around here, and that's the fast schedule. Every dog and his cat has his finger in the building process here.

[Russel Ray]

Originally Posted by Greg Fretwell

As for the fact that defective equipment trips a GFCI, I don't know what you tell the customer.

Recommend further evaluation by a licensed electrician.

Originally Posted by Greg Fretwell

What do you tell them when you point out the frayed extension cords and overloaded outlets?

That extension cords (frayed or otherwise) and overloaded outlets are a major cause of fires in our homes and that adding extension cords does not provide more electricity. There's only so much electricity coming into the house, and if they find themselves using outlet multipliers or extension cords as permanent wiring, they need more outlets and possibly an increase in service capacity. Recommend consulting with a licensed electrician for options.

[jtedesco1]

Wired for Safety (video clip on safety of home electrical wiring, AFCI's and GFCI's) (transcript). Also, Higher Quality Version

[Patrick Bolliger]

Great video Joe.....How can I save it ??

[jtedesco1]

http://www.esfi.org/

See their Library and the order form for the video.

http://www.bussmann.com/library/docs...lash-Blast.pdf