GFCI's and the why?

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I am not sure I understand the question. If something fails, why do you expect it to behave as though it had not failed?
 
MichaelHoltJr said:
When a GFCI fails, why does it continue to provide power through the circuit though the protection from electrical shock is still present? Why not have the device completely deenergize the circuit in its entirety?
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The new ones are not supposed to reset if they go bad but I do not think any just shut down on their own.
 
MichaelHoltJr said:
When a GFCI fails, why does it continue to provide power through the circuit though the protection from electrical shock is still present? Why not have the device completely deenergize the circuit in its entirety?
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I don't know if you have noticed but they put a "test" button on the device and have a recommended test period.

Do you think that you can design a device that will constantly test it's self and still fit in a box and still sell for under $20.

What I'm saying is that it's one thing to wish for a perfect device and other to actually design and build said device.

Now the good news is that with technology constantly improving one day you will probably see a device that will not only shut it's self down but call you on your cell phone ( brain implant ) and let you know it's bad.
 
I think what Michael may be referring to is that sometimes a GFCI even when tripped allows a small amount of current to pass thru to the other outlets. This happened to my friend recently. He tripped the gfci and thought he could work downstream. Much to his surprised he got a bit of a rude awakening.
 
Dennis Alwon said:
I think what Michael may be referring to is that sometimes a GFCI even when tripped allows a small amount of current to pass thru to the other outlets. This happened to my friend recently. He tripped the gfci and thought he could work downstream. Much to his surprised he got a bit of a rude awakening.
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Did he replace the GFCI device with a new one? I would consider this to be a defective device.

As far as I know ( I'm actually brain dead ) a properly functioning GFCI will not allow current flow when tripped. Since you would have no idea if it's working properly it's important to test the circuit.
 
Dennis Alwon said:
I think what Michael may be referring to is that sometimes a GFCI even when tripped allows a small amount of current to pass thru to the other outlets. This happened to my friend recently. He tripped the gfci and thought he could work downstream. Much to his surprised he got a bit of a rude awakening.
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Interesting, you got my attention. Even though you freind may have not followed good safe electical practices and procedures I woud have probably done the same thing as he did an assumerd that a tripped GFCI outlet meant that the circuit was disconnected which sounds reasonable.
It is a good topic to be brought up in that shoulod one assume that a tripped GFCI be considered a disconnect? This should be an eyeopenner in that we should turm off the breaker and de-energize the circuit.
But when he said he was bit it doesn't take much current to make you sit up and take notice. A common 7w night light is rated 60ma which is way moy that the 10-20ma "can't let go" level.
Thanks for the heads up and a leason learned.


Electric Current
(1 second contact) Physiological Effect
1 mA Threshold of feeling, tingling sensation.
10-20 mA "Can't let go!" current - onset of sustained muscular contraction.
100-300 mA Ventricular fibrillation, fatal if continued.
 
I cannot say that all gfci will do that as I have worked on them with the receptacle tripped. I would assume this is not the case in general however I have seen voltage on the load side of dimmers when the dimmer was off.
 
Older GFCIs would fail in the energized conduit. Pipe threaders will cause them to fail I found out. the UL product standard has been changed twice in the last 8 years, and the GFCIs no longer fail energized, and have some means to tell you they have failed, light on, or light off.
 
Also if the gfci was wired incorrectly, they will trip, but still have power. I guess I should have said the older ones would do that, as Iwire said the new ones should not work if wired incorrectly.
 
Dennis Alwon said:
I think what Michael may be referring to is that sometimes a GFCI even when tripped allows a small amount of current to pass thru to the other outlets. This happened to my friend recently. He tripped the gfci and thought he could work downstream. Much to his surprised he got a bit of a rude awakening.
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Has to be defective. If it lets current through how is it supposed to protect people? Maybe a welded contact?

tom baker said:
Older GFCIs would fail in the energized conduit. Pipe threaders will cause them to fail I found out. the UL product standard has been changed twice in the last 8 years, and the GFCIs no longer fail energized, and have some means to tell you they have failed, light on, or light off.
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To your first two sentences::?:?

To the last one - efforts have been made to make them fail to deenergized state - is there any gurantee they will always do so? Mechanical devices do fail. Welded contacts would seem to me to bypass any GFCI driver circuitry whether it works or not.
 
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