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fifty nine

join:2002-09-25
Sussex, NJ
kudos:2

Why don't GFCI outlets fail completely

I pushed the "test" button in the master bedroom bathroom GFCI tonight. It's the last of the original GFCI outlets. I replaced everything else because they tripped with the high RF field from my ham radios.

Nothing. Yup, the GFCI was dead. But what's more worrisome is that the GFCI was now offering NO protection whatsoever... It still works as a regular outlet, sans ground fault protection.

Now riddle me this... Are they supposed to fail that way? To me it would make sense if they failed the other way - i.e. shut the power off and refused to turn back on until you replace the defective outlet. This way they are safe - they cut power unless they are providing ground fault protection.

TheMG
Premium
join:2007-09-04
Canada
kudos:3
Reviews:
·NorthWest Tel
said by fifty nine:

Nothing. Yup, the GFCI was dead. But what's more worrisome is that the GFCI was now offering NO protection whatsoever... It still works as a regular outlet, sans ground fault protection.

Thus why the instructions on most GFCI receptacles and breakers indicate to test them regularly, which very few people actually do.

said by fifty nine:

Are they supposed to fail that way? To me it would make sense if they failed the other way

The electronic circuitry in these receptacles detects an imbalance between live and neutral conductors, energizing a trip coil if the current difference exceeds a set threshold. Obviously, if the electronics fail (such as due to a power surge), they won't be able to energize the coil and trip the GFCI.


nunya
LXI 483
Premium,MVM
join:2000-12-23
O Fallon, MO
kudos:13
reply to fifty nine
I've had them fail "on" many times. That's one good reason to remember to test them often.
--
I just might be the most "licensed" S.O.B. you know.

Zach1
Premium
join:2006-11-26
NW Minnesota
reply to fifty nine
The latest designs are supposed to fail open and not reset. Leviton calls theirs Smartlock Pro and Pass & Seymour; SafeLock. The older designs often fail without any obvious indication of failure aside from the 'Test' button not working or, worse yet, failure to clear a real-world fault. Even with the new ones, it's recommended to test monthly.


fifty nine

join:2002-09-25
Sussex, NJ
kudos:2
I test mine monthly or so, which is how I found this one. With little kids in the house I'm replacing it with a TR GFCI receptacle so I'm ready when they start walking around.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to Zach1
said by Zach1:

The latest designs are supposed to fail open and not reset. Leviton calls theirs Smartlock Pro and Pass & Seymour; SafeLock. The older designs often fail without any obvious indication of failure aside from the 'Test' button not working or, worse yet, failure to clear a real-world fault. Even with the new ones, it's recommended to test monthly.

My last one in the bathroom failed that way. Tripped and would not reset. Bought it at Lowes.

westom

join:2009-03-15
kudos:1
reply to fifty nine
said by fifty nine:

Now riddle me this... Are they supposed to fail that way?

Yes. All original GFCIs failed that way - dangerously. Are another example of why homes should earth 'whole house' protection.

Those original generation GFCIs (ie based in National Semiconductor's LM1851) were recently replaced by a new design that will trip with power loss and will not reset if damaged.

lutful
... of ideas
Premium
join:2005-06-16
Ottawa, ON
kudos:2
reply to fifty nine
said by fifty nine:

Now riddle me this... Are they supposed to fail that way?

Most do ... American Society of Home Inspectors published a GFCI study in 1999:

21% of GFCI circuit breakers and 19% of GFCI receptacles tested did not provide GFCI protection. Yet, the circuit remained energized!

In the examined cases, failures of the GFCI sensing circuits were mostly due to damage to the internal transient voltage surge protection (metal-oxide varistors) that protect the GFCI sensing circuit. This damage resulted from voltage surges from lightning and other transients.

In areas of high-lightning activity, such as Southwest Florida, the failure rate for GFCI circuit breakers was more than 57%.


John97
Over The Hills And Far Away
Premium
join:2000-11-14
Spring Hill, FL
kudos:1
Reviews:
·Bright House Net..
·ooma
reply to fifty nine
The previous owner of my house was some kind of GFI fanatic... I had to remove a bunch of them because he had up to 3 or 4 of them in-line in some places. I now have about 5 or 6 spares left sitting in a box in my garage.

For example, I have a 10x16 shed out back with water and electric. The electric feed runs from a GFI on the exterior of the house out to the shed (buried) where it came out to a GFI outlet, then up to a light switch with another GFI outlet next to it.

The GFI on the exterior of the house died (wouldn't reset). I removed the redundant GFI's in the shed and replaced them with regular outlets. Then I used one of the removed GFI's to replace the failed one.
--
So put me on a highway, and show me a sign.
And take it to the limit one more time...

lutful
... of ideas
Premium
join:2005-06-16
Ottawa, ON
kudos:2
said by John97:

The GFI on the exterior of the house died (wouldn't reset). I removed the redundant GFI's in the shed and replaced them with regular outlets.

Some photos of catastrophic failure of outdoor GFI (?) outlets: »forums.mikeholt.com/showthread.p ··· t=133031

I wondered why electricians do not use circuit breakers incorporating GFCI function for all bathroom/garage/shed/outdoor outlets. I will ask for that as I plan to upgrade my panel.


cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7
said by lutful:

I wondered why electricians do not use circuit breakers incorporating GFCI function for all bathroom/garage/shed/outdoor outlets. I will ask for that as I plan to upgrade my panel.

Cost. $30-40 for a GFCI breaker vs. $8-10 for a GFCI outlet. That's big box store pricing. I don't know what a supply house pricing would be, but I can't imagine that the pricing wouldn't be at least proportionally similar.


Portmonkey
My watch stopped
Premium
join:2004-04-09
Southern IL
Depending on how many outlets, it's sometimes cheaper to buy the breakers like in a basement that tends to flood on occasion or a large kitchen with several outlets near the counter-tops, especially when you get a discount for being a regular customer that usually makes a large purchase. I don't know much about this stuff (slowly learning) and just volunteer to help sometimes on the big jobs, but often see the GFCI breakers getting installed.
--
We've gone from the way things really are, to how someone wants them to be.

Speedy Petey

join:2008-01-19
said by Portmonkey:

Depending on how many outlets, it's sometimes cheaper to buy the breakers like in a basement that tends to flood on occasion or a large kitchen with several outlets near the counter-tops, especially when you get a discount for being a regular customer that usually makes a large purchase.

Nope. Still MUCH more expensive.

You only need ONE $15 GFI receptacle to do the SAME job as a $50 GFI breaker. 99.9% of the time the CUSTOMER is not willing to pay the extra cost. I do NOT get why this would be blamed on the electrician.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to lutful
said by lutful:

said by fifty nine:

Now riddle me this... Are they supposed to fail that way?

Most do ... American Society of Home Inspectors published a GFCI study in 1999:

21% of GFCI circuit breakers and 19% of GFCI receptacles tested did not provide GFCI protection. Yet, the circuit remained energized!

In the examined cases, failures of the GFCI sensing circuits were mostly due to damage to the internal transient voltage surge protection (metal-oxide varistors) that protect the GFCI sensing circuit. This damage resulted from voltage surges from lightning and other transients.

In areas of high-lightning activity, such as Southwest Florida, the failure rate for GFCI circuit breakers was more than 57%.

You would be surprised at the number of circuit breakers that won't trip and clear an overload. We had to resort to an expensive test set and manpower to routinely test them. These devices gives those not trained in the field a false sense of protection


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to lutful
said by lutful:

said by John97:

The GFI on the exterior of the house died (wouldn't reset). I removed the redundant GFI's in the shed and replaced them with regular outlets.

Some photos of catastrophic failure of outdoor GFI (?) outlets: »forums.mikeholt.com/showthread.p ··· t=133031

I wondered why electricians do not use circuit breakers incorporating GFCI function for all bathroom/garage/shed/outdoor outlets. I will ask for that as I plan to upgrade my panel.

After looking at some of the pictures I wonder "Do you feel safer" being forced to install these devices? Another fallacy of the NEC.


fifty nine

join:2002-09-25
Sussex, NJ
kudos:2
reply to westom
said by westom:

Those original generation GFCIs (ie based in National Semiconductor's LM1851) were recently replaced by a new design that will trip with power loss and will not reset if damaged.

Define trip with power loss.

New GFCI outlets I've installed to replace the old ones don't trip with power loss, unless you mean when they fail to provide protection.

It would also be pretty annoying to go resetting GFCIs all over the house every time there is a power dip or power cut.


fifty nine

join:2002-09-25
Sussex, NJ
kudos:2
reply to Portmonkey
said by Portmonkey:

Depending on how many outlets, it's sometimes cheaper to buy the breakers like in a basement that tends to flood on occasion or a large kitchen with several outlets near the counter-tops, especially when you get a discount for being a regular customer that usually makes a large purchase. I don't know much about this stuff (slowly learning) and just volunteer to help sometimes on the big jobs, but often see the GFCI breakers getting installed.

I don't know why a GFCI breaker would be cheaper when you can chain regular outlets to the "load" terminals and have protection on them.


cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7
reply to Jack_in_VA
said by Jack_in_VA:

After looking at some of the pictures I wonder "Do you feel safer" being forced to install these devices? Another fallacy of the NEC.

Reading the explanation of what caused the failure, I don't see how the GFCI is particularly at fault. There is obvious signs of severe corrosion on the terminals and it was used in either an unprotected box and/or a marine environment. It wasn't designed to function in such an environment so how exactly is it suppose to protect in one?

But to answer your question, yes, I do feel safer. Yes they may fail in a manner that they don't provide protection. But they can also do their job and trip protecting you. If they weren't there at all, it would be guaranteed that they would not provide protection.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
To bet you life on a device that may or may not work is foolish. I know how to make myself safe working on electrical but the general population does not. False assumptions are dangerous.


fifty nine

join:2002-09-25
Sussex, NJ
kudos:2

1 recommendation

said by Jack_in_VA:

To bet you life on a device that may or may not work is foolish. I know how to make myself safe working on electrical but the general population does not. False assumptions are dangerous.

I don't bet my life on GFCI outlets. However they are an extra layer of protection. Hypothetical example - you're in the bathtub taking a hot bath. There's a light fixture above it. Earthquake rumbles through and your house is damaged to the point where the fixture falls into the tub with a live wire. You've taken precautions but sh*t happened. The GFCI is there as a fallback so you don't get killed.

It's like having airbags, seatbelts and other safety features in cars. You may be the safest driver in the world but some drunk or idiot on the cellphone could come plowing down the wrong way and hit you head on.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
said by fifty nine:

I don't bet my life on GFCI outlets. However they are an extra layer of protection. Hypothetical example - you're in the bathtub taking a hot bath. There's a light fixture above it. Earthquake rumbles through and your house is damaged to the point where the fixture falls into the tub with a live wire. You've taken precautions but sh*t happened. The GFCI is there as a fallback so you don't get killed.

Fixture falls into tub....Light fixtures generally are not on GFCI protected circuits but let's assume it was. GFCI defective and doesn't trip....results = disaster. Anyone who puts their life in a device that is known to have problems is foolish.


cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7
reply to Jack_in_VA
said by Jack_in_VA:

To bet you life on a device that may or may not work is foolish. I know how to make myself safe working on electrical but the general population does not. False assumptions are dangerous.

No one is betting their life. A GFCI isn't designed to give anyone a false assumption that they can recklessly use electrical devices in wet or unsafe conditions anymore then seatbelts and airbags give a driver a license to be reckless. They are there as a precaution but not as a end all be all failsafe.


fifty nine

join:2002-09-25
Sussex, NJ
kudos:2
reply to Jack_in_VA
said by Jack_in_VA:

Fixture falls into tub....Light fixtures generally are not on GFCI protected circuits but let's assume it was.

Doesn't have to be a light, it could be a plugged in hairdryer or electric shaver on the countertop that fell into the tub.

GFCI defective and doesn't trip....results = disaster. Anyone who puts their life in a device that is known to have problems is foolish.

That's assuming the GFCI is defective. If it's not there in the first place there is no chance of it saving your life. If it's there and working (which is why you test it frequently) then it has a chance of being another layer of protection.

It's like wearing steel toed boots. You don't drop hammers on your foot but just in case one does drop on your foot it won't crush your toes.

It's also like using a transfer switch. You can be careful and backfeed your panel via the dryer outlet in the event of a power outage because we all know you're always careful and remember to turn off the main breaker first... at least until you forget when you're tired and it's dark. A transfer switch eliminates that possibility. Yes the switch can be defective and backfeed anyway but so what, it's a remote possibility.


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3
reply to Jack_in_VA
said by Jack_in_VA:

After looking at some of the pictures I wonder "Do you feel safer" being forced to install these devices? Another fallacy of the NEC.

If you liked GFCI’s being pushed by the code, your going to love the “smart outlet” aka electrical fault circuit interrupter (EFCI) that is being proposed as a new code requirement.

It is described as;

"The EFCI installed in an electrical outlet will automatically configure its trip level to match whatever electrical device is plugged into its receptacle. When an electrical device plug is installed, the EFCI reads the safe limit from a RightPlug® tag embedded in the plug. RightPlug uses wireless transponder communication defined by ISO 14443B to transfer electrical device power ratings from the device plug to the EFCI. The tag read range is designed to be less than 1 cm (about 3/8”). The following picture shows a tag molded into an electrical plug (translucent computer-generated view - below)."

“An EFCI outlet continuously looks for a tag within its read range on each receptacle. When a tag is placed within its read range, an EFCI will read the hold current level from the tag and set a trip level above the hold level. For example, if it reads a Level 8 hold current, it will pass 4 Amps and trip on over-current conditions. If the tag is removed from the read range, the EFCI returns to a maximum 15 Amp trip level for a 15 Amp outlet or 20 Amps for a 20 Amp outlet (default). When another device tag comes within its read range, the EFCI will adopt a new trip level associated with that hold current.”

»www.2d2c.com/efci.php
»www.rightplug.org/

Wayne
--
"It is sobering to reflect that one of the best ways to get yourself a reputation as a dangerous citizen these days is to go about repeating the very phrases which our founding fathers used in the struggle for independence." - Charles A. Beard


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
OMG

I note from their website that safety is not even mentioned but "Smart Energy" sure is. The amount of "control" these smart energy advocates want is simply alarming. They not only will have the ability to monitor and control our overall usage "smart meters" but will have the ability to monitor each individual usage connected to a receptacle etc.

KEY OBJECTIVES

Maintain, expand and distribute the RightPlug standard.
Develop and maintain standard compliance procedures.
Manage licensing of the RightPlug trademark(s).
Promote adoption of the RightPlug standard worldwide.
Provide internet-based product authentication services.

SMART ENERGY

Smart Grid, Smart Meters and Smart Appliances are all playing a part in helping us to conserve energy and reduce greenhouse gas emissions. Unfortunately, the cost of "smart" prevents it's application in lower cost products that make up the majority of electrical devices.

RightPlug digital encoding, in conjunction with RightPlug compatible Smart Outlets, enables "not-so-smart" electrical devices to interact with the smart grid with minimal extra cost in the appliance. Increasing the number of devices that can interact with Smart Grid technologies drastically increases the efficacy of demand response and cost reduction efforts.


49528867
Premium
join:2010-04-16
Fort Lauderdale, FL
kudos:3
said by Jack_in_VA:

OMG

I note from their website that safety is not even mentioned but "Smart Energy" sure is. The amount of "control" these smart energy advocates want is simply alarming.

Not to mention the cost, a $4.99 plug at Home Depot once wised up will run say $24.99 and a 50 foot "smart" extension cord maybe what $75.

Wayne

--
"It is sobering to reflect that one of the best ways to get yourself a reputation as a dangerous citizen these days is to go about repeating the very phrases which our founding fathers used in the struggle for independence." - Charles A. Beard


SparkChaser
Premium
join:2000-06-06
Downingtown, PA
kudos:4
Reviews:
·Verizon FiOS
reply to fifty nine
First paragraph

Electrical Fault Circuit Interrupter (EFCI)

Electrical Fault Circuit Interrupters (EFCI) are designed to protect against top electrical fire ignition causes including poor connections and high resistance points in branch circuit wiring, overloads in utilization equipment and open neutral connections.