Would you.....

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I went on a service call to a large custom home that was only a couple of years old. The home was wired with #14 and the runs were quite long. The homeowner worked out of his home and had an office set up on the upper level. The panel was in the basement.

He had a lot of computer equipment, laser printers, etc. His voltage kept dropping low enough that his computers would shut down. He had a power monitor connected to the computers and he could see the voltage dropping.
I can't remember the exact voltage drop but it was something like 12 to 15 percent when I checked it with my voltage drop tester.

I ended up running a dedicated #12 20amp circuit to the room and the voltage drop measured about 5 percent if I remember right. Anyways it solved the problem he was having.

It seems to me on some of these very large homes, like this one, that the #14 guage runs can become quite long and seem to have quite a bit of lighting on them so that when anything with a siginificant load is plugged into an outlet voltage drop can become a problem. His breakers were holding up fine it was his computers that were having problems with the voltage drop.

He may very well have had the same problem even if the wiring was #12 but the larger wire I'm sure would have helped with the voltage drop. I think a lot of it comes down to running #14 to cut costs but also loading up the circuits too much to save money as well. They load up the circuit with can lights and run the receptacles off the same circuit as well.

I can see this as becoming more of a problem when they have to install AFCI breakers for all the circuits. They'll try to skimp on the number of circuits as much as possible to reduce the number of AFCI breakers they install.

Does anyone do voltage drop calculations when running these circuits in overly large homes?

Often times they don't install panels throughout the home but install everything in an equipment room located in the basement. This can lead to some long runs by the time you get up to the upper levels.
 
aline said:
I went on a service call to a large custom home that was only a couple of years old. The home was wired with #14 and the runs were quite long. The homeowner worked out of his home and had an office set up on the upper level. The panel was in the basement

Does anyone do voltage drop calculations when running these circuits in overly large homes?

Often times they don't install panels throughout the home but install everything in an equipment room located in the basement. This can lead to some long runs by the time you get up to the upper levels.
Click to expand...

Exactly, make efficent.
 
aline said:
I went on a service call to a large custom home that was only a couple of years old. The home was wired with #14 and the runs were quite long. The homeowner worked out of his home and had an office set up on the upper level. The panel was in the basement.

He had a lot of computer equipment, laser printers, etc.
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What is your point? That homes should be wired with the expectation that everyone is going to run a server, mainframe and print shop out of their bonus room? NOBODY, no matter how large or expensive a home is, should expect that whatever they choose to do, is going to be adequate.



...It seems to me on some of these very large homes, like this one, that the #14 guage runs can become quite long and seem to have quite a bit of lighting on them so that when anything with a siginificant load is plugged into an outlet voltage drop can become a problem. His breakers were holding up fine it was his computers that were having problems with the voltage drop.

He may very well have had the same problem even if the wiring was #12 but the larger wire I'm sure would have helped with the voltage drop. I think a lot of it comes down to running #14 to cut costs but also loading up the circuits too much to save money as well. They load up the circuit with can lights and run the receptacles off the same circuit as well.[/quote]

#14 isn't run to "cut costs." #14 is run because that is adequate and all that is required. In a large home, using #14 will also result in a greater quantity of circuits when the 3 watts per sq. ft. rule is used to determine how many general purpose circuits are needed. I doubt anybody considerd voltage drop unless the HRs are nearing 100 feet.

I can see this as becoming more of a problem when they have to install AFCI breakers for all the circuits. They'll try to skimp on the number of circuits as much as possible to reduce the number of AFCI breakers they install.
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Wiring to minimum code is not skimping. And I'd venture a guess that the AFCI rule won't change the number of circuits at all, because in a spec home you're already running the minimum number of circuits.

And don't think for a minute that just because a home is a large McMansion that it's not a spec home. Don't let the granite countertops, stainless appliances, and spacious bathroom and tray ceilings fool you. They're still built at the lowest possible cost.

Does anyone do voltage drop calculations when running these circuits in overly large homes?

Often times they don't install panels throughout the home but install everything in an equipment room located in the basement. This can lead to some long runs by the time you get up to the upper levels.
Click to expand...

This custom homeowner's problem was simple. He was overloading his circuits. If he had #12 initially, he'd probably have another computer and another printer and he'd STILL have problems with overloaded circuits.
 
Ok, we are discussing design issues, and it's easy to critique someone else's electrical design. HRs too long, Voltage drop, too few circuits, etc. The problem with such discussions is they leave the most important element of electrical design out of the discussion: What sort of design was the HO willing to pay for?

I'm not addressing anyone in particular but I really love Super-Electrician's who enjoy criticizing designs they see as inferior to those they would create. Not every electrical system I design is super duper. If my customer is paying for a "Class A" job, that's what I deliver, if they want to spend the least amount of money possible while still being legal, I can deliver that too.

Electrical wiring is not one size fits all. Some of my jobs are true masterpieces, others are code compliant and minimalistic in design. All of my jobs meet NEC codes and exhibit journeyman level craftsmanship, but it's the design that is different.

I can blow through tract homes all day at $2.70 a foot or I can wire a custom home with an over engineered electrical system and 4 subpanels, if someone's willing to pay for it.

The customer is entitled to get what they pay for. If they want a house wired in #12 and flex conduit and they're willing to pay for it, that's what they get. If their primary concern is cost, they will be getting #14 and plastic boxes. It doesn't make me an inferior contractor, it means that not all my customers are wealthy.

What may seem like an inferior design to some, may actually be a rather elegant solution for a customer on a tight budget.
 
My point is if you're going to run a 15 amp circuit 150 feet and factor a load of 12 amps what size wire would you need to meet the recommended 3% voltage drop?

You should be able to load a 15 amp circuit with 12 amps and not have a voltage drop of 15%. To me thats poor design. I don't blame the electrician though. Lowest price gets the job.

According to this calculator you would need a #8.
http://www.elec-toolbox.com/calculators/voltdrop.htm
 
satcom said:
So your lost in space also!
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LOL... Not exactly....I saw the light ...

star-wars-smiley-008.gif




satcom said:
I give up, time to enjoy the better things in life.
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Come to the not-so-dark side, Luke....
star-wars-smiley-023.gif



satcom said:
If everyone is happy, with the way they layout the circuits, so be it. The code does not guide efficent work, it only gives you a base to start from. There are no rules, laws, or standards that tell you to do efficent jobs.
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I have yet to come across a satisfactory answer as to why to use #12 exclusively.
In a previous existance, I was a member of the the Church of the #12. I was converted by some crazy coot...I am now a member of the Church of the Alimighty Backstabber.

If someone can convince me to join the Church of the Reformed using compelling arguments, I will consider it.

car-smiley-004.gif

Until then, it'll be all #14 unless a larger conductor is required.
 
aline said:
My point is if you're going to run a 15 amp circuit 150 feet and factor a load of 12 amps what size wire would you need to meet the recommended 3% voltage drop?

You should be able to load a 15 amp circuit with 12 amps and not have a voltage drop of 15%. To me thats poor design. I don't blame the electrician though. Lowest price gets the job.

According to this calculator you would need a #8.
http://www.elec-toolbox.com/calculators/voltdrop.htm
Click to expand...

Why are we assuming it will ever see 12A?

Why not assume 3A...or 0A...or 30A...just as long as we are assuming :roll:

It all boils down to this:
The customer shall receive only what the customer has paid for.


If they know they are running a money printing business in their business, it would be prudent to let the EC in on the secret.
 
HaskinsElectric said:
Ok, we are discussing design issues, and it's easy to critique someone else's electrical design. HRs too long, Voltage drop, too few circuits, etc. The problem with such discussions is they leave the most important element of electrical design out of the discussion: What sort of design was the HO willing to pay for?

I'm not addressing anyone in particular but I really love Super-Electrician's who enjoy criticizing designs they see as inferior to those they would create. Not every electrical system I design is super duper. If my customer is paying for a "Class A" job, that's what I deliver, if they want to spend the least amount of money possible while still being legal, I can deliver that too.

Electrical wiring is not one size fits all. Some of my jobs are true masterpieces, others are code compliant and minimalistic in design. All of my jobs meet NEC codes and exhibit journeyman level craftsmanship, but it's the design that is different.

I can blow through tract homes all day at $2.70 a foot or I can wire a custom home with an over engineered electrical system and 4 subpanels, if someone's willing to pay for it.

The customer is entitled to get what they pay for. If they want a house wired in #12 and flex conduit and they're willing to pay for it, that's what they get. If their primary concern is cost, they will be getting #14 and plastic boxes. It doesn't make me an inferior contractor, it means that not all my customers are wealthy.

What may seem like an inferior design to some, may actually be a rather elegant solution for a customer on a tight budget.
Click to expand...
I completely agree with what you're saying. Voltage drop is not a concern with the electrical code and is a design issue but I don't think most electricians even bother to mention to the homeowner that they may wish to increase the number of circuits or have larger wire installed for longer runs to reduce voltage drop problems.

This could be a way to increase their profits if they can upsell the design. Most homeowners are too cheap to buy into this though.

In these large homes I see these circuits exeeding 100ft. quite often.

I'm not saying the contractor should just do this at his own expense but should at least make the customer aware of it. Maybe even have him sign something saying he was too cheap to pay for a better design so if he experiences problems down the road he has noone to blame but himself.
 
By the way I install #14 too just like everyone else around here.
I just think if the runs are going to become exsessivly long that I should at least let the homeowner know that voltage drop could become an issue.
I would let him decide if he wants to spend the money to do anything about it.

Why would the homeowner mention to you what he plans to plug into his outlets?

He has no clue about electrical. He doesn't know about voltage drop, amperage, etc. He's getting a brand new multi million dollar home. Surely in his mind his new electrical system ought to handle anything he's going to plug into it.
 
HaskinsElectric said:
Ok, we are discussing design issues, and it's easy to critique someone else's electrical design. HRs too long, Voltage drop, too few circuits, etc. The problem with such discussions is they leave the most important element of electrical design out of the discussion: What sort of design was the HO willing to pay for?
Click to expand...

Or, the builder/developer. There are times when the HO is not even part of the equation by the time the rough wiring starts.
 
aline said:
By the way I install #14 too just like everyone else around here.
I just think if the runs are going to become exsessivly long that I should at least let the homeowner know that voltage drop could become an issue.
I would let him decide if he wants to spend the money to do anything about it.

Why would the homeowner mention to you what he plans to plug into his outlets?

He has no clue about electrical. He doesn't know about voltage drop, amperage, etc. He's getting a brand new multi million dollar home. Surely in his mind his new electrical system ought to handle anything he's going to plug into it.
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He also has no reason to expect that anything he plans on doing has been taken into consideration.

Often, homeowners expect that they'll be able to draw 3 baths and run the UG sprinklers simultaniously. Or they won't feel a pressure loss in a shower if a toilet is flushed. Just because they tend to assume that a brand new house today will have none of inconveniences and quirks of an older home.

Minimum code isn't bad, it's just not adequate for anything beyond minimum expectations.
 
frenchelectrican said:
it pretty weak right now on between USD/EURO

1,000.00 USD = 673.33 EURO

1,000.00 EURO= 1,485.15 USD

as today exchange rate.

Merci, Marc
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Yes, the US dollar is weak. If he got paid 4700 Euros he might even make a profit after the exchange.:rolleyes:
 
LawnGuyLandSparky said:
This custom homeowner's problem was simple. He was overloading his circuits. If he had #12 initially, he'd probably have another computer and another printer and he'd STILL have problems with overloaded circuits.
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So is connecting equipment that draws 12 amps on a 15 amp circuit considered overloading the circuit? I would think that if he was just overloading the circuit the breaker would trip instead of his computers shutting down due to low voltage. It's also possible that if he had #12 wire maybe that would have been just enough to keep the voltage drop low enough to not shut down the equipment.
Does this mean that anytime equipment is having problems due to voltage drop it's because the equipment is overloading the circuit and not because the wire wasn't sized properly to reduce the voltage drop to an acceptable level?

Celtic said:
Why are we assuming it will ever see 12A?

Why not assume 3A...or 0A...or 30A...just as long as we are assuming
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If you pay for a 15 amp circuit wouldn't you assume you should be able to load the circuit with 12 amps without so much voltage drop that your equipment shuts down? I sure wouldn't expect to maintain the 5% voltage drop that's recommended though.

If I was assuming 0A I wouldn't even bother running a circuit and if I was assuming 30A I wouldn't be running #14. :)
I assume 12 amps because I feel I should be able to load a 15 amp circuit with 12 amps without having problems.

My point is to just say wiring a home with anything other than #14 wire is a complete waste of time and money isn't necessarily true. It depends on the situation and whether or not they're willing to pay for it. I know this is a design issue and not a code issue and people aren't willing to pay for it but I wouldn't agree that it's a waste of time and money to run #12 in some cases.
 
today's update...

today's update...

Well the electrician started running wire today. My buddy was at his house late this afternoon so I stopped in to look around. Want to know what $4700 buys when the EC provides the wire? A master bath and smaller bath that are side by side sharing receptacles. Hmm..I think that could be a violation. Wires stapled above the box properly, but no secondary staple close to the top plate, and there is no slack in the wire. He also pulled a run that rides over the dryer vent duct. On the bright side, he did run a dedicated circuit to the washing machine receptacle. However, that run passes through the first floor framing and the only support is a hole in a brace between two studs. No staples at all and the ceilings are 9 feet.

Hmm...maybe I should take pictures :grin:

c2500
 
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