# Nuisance tripping???



## tdsaysell

Please can anyone help me i cant find a technical definition for the term NUISANCE TRIPPING. I think it is to do with discrimination of protective devices however iam not 100% sure and I cant seem to find any information on this term anywhere

Please could someone help me Thank you?


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## Buck Parrish

"Frequency of Occurence" Is some times used with AFCI and GFCI . A normal breaker should not have "nusance tripping".


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## tdsaysell

Thanks but it doesn't really help me what are AFCI and GFCI.


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## RIVETER

tdsaysell said:


> Thanks but it doesn't really help me what are AFCI and GFCI.


You're kidding, right?


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## Grimlock

tdsaysell said:


> Thanks but it doesn't really help me what are AFCI and GFCI.


Sometimes AFCI / GFCI breakers trip because of events that mimic trip conditions.

Examples:

Voltage drop on a circuit fed by a GFCI Breaker can cause the breaker to trip due to loss in the electrical wiring greater than 6ma.

Cheap surge protector power strips can cause GFCI and AFCI breakers to trip due to the MOV shunting to ground at a low clamping voltage.

Any surge in the electrical system can cause a temporary malfunction of a GFCI and AFCI which can be called "NUISANCE TRIPPING" also.


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## RePhase277

RIVETER said:


> You're kidding, right?


Do you guys never notice this is the UK section? The terms are different between the US and UK. A GFCI is an RCD in England.


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## Grimlock

InPhase277 said:


> Do you guys never notice this is the UK section? The terms are different between the US and UK. A GFCI is an RCD in England.


RCD?

What does that stand for?


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## Bob Badger

RIVETER said:


> You're kidding, right?


How is that helpful other than stroking your own ego? 

(Much like this post)


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## Zog

tdsaysell said:


> Please can anyone help me i cant find a technical definition for the term NUISANCE TRIPPING. I think it is to do with discrimination of protective devices however iam not 100% sure and I cant seem to find any information on this term anywhere
> 
> Please could someone help me Thank you?


Nuisance Tripping is a dirty word in my book, 99% of the time that term is used it means someone just dosen't understand what is going on. 

I don;t htink you will find a real definition anywhere, but as a breaker guy, to me it means the breaker is tripping at a I/t faster than it should, this can be caused by mechanical issues withing the breaker, trip unit failure to defaut settings, failed or improper CT sizing/taps. 

Why do you ask and what type of breaker are you refering to? The reasons and solutions will vary greatly depending on the type of equipment you are refering to .


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## Grimlock

Nevermind, I got it:

*R*esidual *C*urrent* D*evice (*RCD*),


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## Bob Badger

Grimlock said:


> RCD?
> 
> What does that stand for?





> *R*esidual *C*urrent *D*evice. This is a sensitive switching device that trips a circuit when an earth fault is detected.


In our terms it is more GFP than GFCI.


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## Grimlock

Bob Badger said:


> *R*esidual *C*urrent *D*evice. This is a sensitive switching device that trips a circuit when an earth fault is detected. .


Too late, your slow today, what happened? Too busy stroking your ego in post #8? :jester::laughing:


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## Bob Badger

Grimlock said:


> Too late, your slow today, what happened? Too busy stroking your ego in post #8? :jester::laughing:


Yeah!:laughing:


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## RIVETER

*nuisance*



InPhase277 said:


> Do you guys never notice this is the UK section? The terms are different between the US and UK. A GFCI is an RCD in England.


 Oh, I'm sorry...I thought it was the Univ. of Kentucky. My bad.


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## RIVETER

*Nuisance*



Bob Badger said:


> How is that helpful other than stroking your own ego?
> 
> (Much like this post)


That is not what I was stroking...but thanks for noticing.

P.S. Is the UK really in England?


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## Grimlock

RIVETER said:


> That is not what I was stroking...but thanks for noticing.


Information overload.....


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## RIVETER

Grimlock said:


> Information overload.....


OK, I'm sorry. Could you define Residual current device, and explain how it comes into play?


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## Bob Badger

RIVETER said:


> That is not what I was stroking...but thanks for noticing.


Pretty sure I could not see that little thing even if I was there, never mind from a few thousand miles.:whistling2:


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## Bob Badger

RIVETER said:


> OK, I'm sorry. Could you define Risidual current device, and explain how it comes into play?


Do you know what GFP is, or are you going to play dumb about that as well?


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## RIVETER

*Nusiance*



Bob Badger said:


> Pretty sure I could not see that little thing even if I was there, never mind from a few thousand miles.:whistling2:


I've heard that many times before, it doesn't hurt anymore.:laughing:


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## Bob Badger

RIVETER said:


> I've heard that many times before, it doesn't hurt anymore.:laughing:



:thumbup::thumbup:


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## Grimlock

RIVETER said:


> OK, I'm sorry.


 
If you're sorry then you'll be here in five minutes with a can of PVC cement to help glue my head back together.










Scotchkote is an acceptable alternatiive.


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## RIVETER

*nuisance*



Bob Badger said:


> Do you know what GFP is, or are you going to play dumb about that as well?


I think I know...but what makes you think that am playing?


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## Bob Badger

RIVETER said:


> I think I know...but what makes you think that am playing?


Yes, I think sometimes you ask questions that you already know the answer to.

If not this time I apologize.

It is my limited understanding that an RCD unit functions much like a GFCI but with a higher trip setting.


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## RePhase277

Bob Badger said:


> Yes, I think sometimes you ask questions that you already know the answer to.
> 
> If not this time I apologize.
> 
> It is my limited understanding that an RCD unit functions much like a GFCI but with a higher trip setting.


Yeah, I believe, from my lurkings on UK and Australian forums, that RCDs generally trip at 30 mA.


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## Grimlock

InPhase277 said:


> Yeah, I believe, from my lurkings on UK and Australian forums, that RCDs generally trip at 30 mA.


AFCIs trip at 30 mA.


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## Zog

Grimlock said:


> AFCIs trip at 30 mA.


No they don't. They don't trip at any current, they use specific arcing voltage waveform signatures pre programed into the embedded chip. 

http://www.afcisafety.org/files/AFCI8pager.pdf


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## Zog

Really? 26 posts and only a few trying to help the OP, much less address it? All the rest bickering, really representing the USA well there guys. Save that for the IBEW forum.


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## Grimlock

Zog said:


> No they don't. They don't trip at any current, they use specific arcing voltage waveform signatures pre programed into the embedded chip.
> 
> http://www.afcisafety.org/files/AFCI8pager.pdf


At 30 mA a Cutler Hammer combination AFCI trips like a GFCI does at 6 mA. I wasn't saying that that was it's only function, just that it trips at 30 mA (In addition to its other attributes).

I'll see if I can find a spec on it.


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## Bob Badger

Zog said:


> No they don't. They don't trip at any current, they use specific arcing voltage waveform signatures pre programed into the embedded chip.
> 
> http://www.afcisafety.org/files/AFCI8pager.pdf


Zog, there is a GFP function in each AFCI, I am not sure of the trip setting but it is included along with the signature mapping.


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## Bob Badger

Zog said:


> Really? 26 posts and only a few trying to help the OP, much less address it? All the rest bickering, really representing the USA well there guys. Save that for the IBEW forum.


Ah there is not a lot to more to say, you pretty much covered it here



> I don't think you will find a real definition anywhere,


To me 'nuisance tripping' is a slang term that is used differently by each person.


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## Zog

Grimlock said:


> At 30 mA a Cutler Hammer combination AFCI trips like a GFCI does at 6 mA. I wasn't saying that that was it's only function, just that it trips at 30 mA (In addition to its other attributes).
> 
> I'll see if I can find a spec on it.


Combo? Well that's different. That's like saying cheeseburgers are made from potatoes and then say, well they come with fries that are made of potatoes.


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## MDShunk

Zog said:


> Combo? Well that's different. That's like saying cheeseburgers are made from potatoes and then say, well they come with fries that are made of potatoes.


Actually, I'm not sure you'll find an AFCI breaker on the market now that doesn't also trip on a 30ma current imbalance.


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## Bob Badger

Zog said:


> Combo? Well that's different. That's like saying cheeseburgers are made from potatoes and then say, well they come with fries that are made of potatoes.


The terminology "Combination type AFCI" does not mean an AFCI/GFCI combination. 

The 2008 NEC now requires the use of combination type AFCIs.


From EC&M


> The combination-type AFCI combines the protection of branch/feeder circuits with increased sensitivity as well as added protection for cord-and-plug-connected equipment.







> What is the difference between a Combination Type AFCI and a Branch/Feeder AFCI?
> 
> The Siemens Combination Type AFCI provides protection against all three types of arcs (series, line-to-neutral, and line-to-ground). The Combination Type meets all the 1999 and later NEC® requirements. It is specifically required by the 2005 NEC® beginning January 1, 2008.
> 
> The original Branch/Feeder AFCI’s provided protection against only two types of arcs (line-to-neutral and line-to-ground). It could used to meet the requirements of the 1999-2002 NEC® and the 2005 NEC® until January 1, 2008.


From here http://www.peterspirito.com/afci_faq.htm#4


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## RyanM

*Continuous Loads*

I know about continuous loads and how they are calculated per NEC. I have never ran across any instances where I had to calculate for continuous loads except for motors. I know circuit breakers only draw about 80% of their rating and for a 20amp that is about 16 amps. Lets say, that I wanted to install some lighting at a commercial builiding that will be on for at least 3 hours and the light is using 18 amps. Should I use a 20 amp breaker or 25 amp breaker? I know the 20 could trip due to heat. Anybody that has experience in this area please respond!!!!


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## tdsaysell

Grimlock said:


> RCD?
> 
> What does that stand for?


 Residual Current Device


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## Carultch

Grimlock said:


> If you're sorry then you'll be here in five minutes with a can of PVC cement to help glue my head back together.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Scotchkote is an acceptable alternatiive.


Is your skull made out of Schedule 40 or Schedule 80?


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## dmxtothemax

RIVETER said:


> Is the UK really in England?


 Me thinks it is other way around !

England is in U K !

I think UK is England, Scotland and Ireland together.


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## dmxtothemax

InPhase277 said:


> Yeah, I believe, from my lurkings on UK and Australian forums, that RCDs generally trip at 30 mA.


You are correct !

But 10ma are also available
but are only used in hospitals and schools.


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## dmxtothemax

tdsaysell said:


> Thanks but it doesn't really help me what are AFCI and GFCI.


AFCI = Arc Fault Circuit Interuptor,


GFCI = Ground Fault Circuit Interuptor.
It's the same as a RCD.


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## Ontario

tdsaysell said:


> Please can anyone help me i cant find a technical definition for the term NUISANCE TRIPPING. I think it is to do with discrimination of protective devices however iam not 100% sure and I cant seem to find any information on this term anywhere
> 
> Please could someone help me Thank you?


*Nuisance Trip* - The unintentional tripping of a circuit breaker/fuse.

(The term 'unintentional' meaning other than in the interests of safety or testing.)


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