Number of outlets

Status
Not open for further replies.

sparks1

Senior Member
Location
Massachusetts
OK so your basic assumption here is that more connections increases the total circuit impedance to the point the breaker will not open during a fault.

Well if you raise the impedance enough you may well put the instantaneous trip out of the picture but you have not put the thermal part of the breaker out of the picture.

If the high impedance circuit has so much impedance it cant trip the thermal part of the breaker it also is not drawing enough current to hurt the conductor.

As far as an over temperature at a specific connection, keep in mind your theory says this high impedance is caused by multiple connections in the circuit, that means the power being dissipated is not at one connection causing high temps, it is a little bit of loss at each connection. And truthfully it will take a ton of properly made connections to cause this to happen at all.

As has been pointed out the length of the circuit conductors has a lot more to do with it than the number of connections.

The people you are calling morons are some very dedicated electricians who hang at these forums because they are into their jobs. They do care about safety, but they want the code to be written with facts, not opinions and personal preferences.

I hope you hang around.
Just for the record...I didn't start byusing the M.... Word . Someone else made reference to it perhaps it was there assumption. Name calling does not belong here. Stick to the point if you have got something worthwhile to say.
 

sparks1

Senior Member
Location
Massachusetts
Just for the record...I didn't start byusing the M.... Word . Someone else made reference to it perhaps it was there assumption. Name calling does not belong here. Stick to the point if you have got something worthwhile to say.

Sure a circuit breaker is nothing more then an over current device to protect the circuit from short circuit current and ground faults . It's nothing more then a bi metal strip liked to a mechanism to open a set of contacts when the breaker become overloaded, short circuit and ground fault.Smaller sizes are rated 10 k AIC (available interrupt current )
Which is more then sufficient for that propose except they don't response fast enough if at all?? I have talked to several local electrician and they concurred this problem with certain brands of breakers ( I won't mention brand names here as Someone else has previously done so.but getting back to the number of outlets why do you think manufactures developed this technology aside from profit. It is most likely a call from public opinion that some should be done because of all the issues with high impedance circuit that would prevent a standard breaker to operate. Have s good day!
 

480sparky

Senior Member
Location
Iowegia
Well, tell ya what. The minute the 2017 comes out (this October or so), rip the page in the back out to make a proposal for the 2020.

Fill it out, attach your documentation, and send it in.

Arguing and bickering on an innernets forum isn't going to change the NEC. Fill out the paperwork, submit it, and let us know when the ROP comes out what the result is.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
Something to ponder.

If the resistance of the circuit is high due to the number of outlets and that resistance is enough to cause an OCPD not to trip due to lower current, that same low current applies to the conductors. If only 14 amps can flow through the OCPD, the same applies to the conductors.

The problem of voltage drop (which also relates to current drop) is more an issue of convenience than safety.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
...but getting back to the number of outlets why do you think manufactures developed this technology aside from profit. It is most likely a call from public opinion that some should be done because of all the issues with high impedance circuit that would prevent a standard breaker to operate. Have s good day!
It was a product developed because a report from the CPSC said there are a large number of dwelling unit fires that are caused by arcing faults that are not being cleared by the currently available OCPDs....note that no one has even proved that self sustaining arcing faults even exist at dwelling unit voltages.

It had nothing to do with high impedances...in fact it was made clear early on in the process that the AFCI could not detect "joule heating" which is most likely caused by a high impedance connection.

They were not designed to work when the circuit impedance limited the fault current....the do no even look for a parallel arcing fault unless the current is 75 amps or greater.
 

kwired

Electron manager
Location
NE Nebraska
Well, tell ya what. The minute the 2017 comes out (this October or so), rip the page in the back out to make a proposal for the 2020.

Fill it out, attach your documentation, and send it in.

Arguing and bickering on an innernets forum isn't going to change the NEC. Fill out the paperwork, submit it, and let us know when the ROP comes out what the result is.

I don't think he can do that. They call proposals "Public Input" now and I think you have to do them via internet now, and AFAIK they only accept PI via "e-submission".
 

sparks1

Senior Member
Location
Massachusetts
Something to ponder.

If the resistance of the circuit is high due to the number of outlets and that resistance is enough to cause an OCPD not to trip due to lower current, that same low current applies to the conductors. If only 14 amps can flow through the OCPD, the same applies to the conductors.

The problem of voltage drop (which also relates to current drop) is more an issue of convenience than safety.

This is the point I'm trying to make .Voltage drop is is the problem there's no disputing that... vd is the total impedance of the circuit starting from the utility transformer. The PO wire is ok due to its size . The total distance is the total impedance component plus the load current plus the number of outlets plus power strips plugged in lowers the available fault current at outlet. Sure you can run a larger wire such as a # 12.
So add one have suggest we should number 12 to correct the vd.
If you start out with 14/2 and run 125' and add in all of the above and dry walk over everything well guess what
The number don't lie ... You do the math .. and if you design yours circuit this way it is wrong!!! This is my professional opinion. As member we of the public I have every right to correct what has been done wrong for years
It simply sloppy workmanship and poor design with no testing of circuits and breakers required after installation to protect member of the public
 

roger

Moderator
Staff member
Location
Fl
Occupation
Retired Electrician
It simply sloppy workmanship and poor design with no testing of circuits and breakers required after installation to protect member of the public
And that is your opinion that is not shared by most if any in this thread.

You've been shown how to submit a PI, if you really believe this is a problem submit one, and FYI, a good number of members here have had proposals accepted.

Roger
 

480sparky

Senior Member
Location
Iowegia
This is the point I'm trying to make .Voltage drop is is the problem there's no disputing that...

So voltage drop is the issue, and not the number of receptacles/outlets on the circuit?

What's the problem then? Voltage drop is already addressed in the Code.



.......This is my professional opinion..........

You have no leg to stand on then. If you want to over-engineer your jobs, you're more than free to do so. But don't force the rest of us to conform to your opinion.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
It simply sloppy workmanship and poor design with no testing of circuits and breakers required after installation to protect member of the public

Protect them from what?

Voltage drop has not been shown to pose a hazard to persons or property.

The first words of NFPA 70 are:

90.1 Purpose

(A) The purpose of this Code is the practical safeguarding of persons or property from hazards arising from the use of electricity.

So, if there is no hazard, right off the get go, the Code does not apply.

(B), paraphrased, says the code applies to safety and does not address efficiency, convenience or future expansion.

The number don't lie ... You do the math .. and if you design yours circuit this way it is wrong!!!

(C), paraphrased, says the Code is not intended to be a design manual.

Your concerns about circuit designs, be they correct or not as a matter of your opinion, or correct or not for real world application, are not concerns of the NFPA.

The FPNs about voltage drop come right out and say the issue of voltage drop is efficiency, and FPNs (or Informational Notes) are for information only and are not enforceable parts of the Code.

When you suggest that design requirements should be enforceable by law, that's fine, it's just that the NEC isn't the document that would cover that. An entirely different set of codes for design would have to be written up and then adopted by jurisdictions to become law.
 

sparks1

Senior Member
Location
Massachusetts
So voltage drop is the issue, and not the number of receptacles/outlets on the circuit?

What's the problem then? Voltage drop is already addressed in the Code.





You have no leg to stand on then. If you want to over-engineer your jobs, you're more than free to do so. But don't force the rest of us to conform to your opinion.

Ok then stay tuned...
I would like to thank you all for your replys
It's all good discussion . We can agree to disagree and before I bring this thread to a final conclusion ... I leave you with this question to ponder for the next code cycle
It a simple question that no one here has yet answered
How many outlets can you put on a residential branch circuit?
Thank again!
Best regards,
Sparks 1
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
Ok then stay tuned...
I would like to thank you all for your replys
It's all good discussion . We can agree to disagree and before I bring this thread to a final conclusion ... I leave you with this question to ponder for the next code cycle
It a simple question that no one here has yet answered
How many outlets can you put on a residential branch circuit?
Thank again!
Best regards,
Sparks 1


There is no limit. I can wire an entire room that has 100 duplex receptacles and have then on one circuit and it would be code compliant. You cannot find anything in the code that would say otherwise unless you are wiring for specific equipment
 

roger

Moderator
Staff member
Location
Fl
Occupation
Retired Electrician
How many outlets can you put on a residential branch circuit?
Thank again!
Best regards,
Sparks 1

More than a bushel basket full, I know because I've done it. :thumbsup:

Roger
 
Status
Not open for further replies.
Top