Residential Wiring

[kwired]

I have never been called back for overload issues on a 15 amp circuit.

I have, well maybe not so much called back because I put in a 15 instead of a 20, but simply because more than one circuit should have been run in the first place with what they are using. Doesn't happen too often in dwellings unless they are using space heaters or portable AC's though.

 

[James L]

To make my point, let me take it to the extreme:

Even ten 15a circuits can not supply certain loads that one 20a circuit can.

Every single plug-in load in my house, except one, functions fine on a 15 amp circuit.

The only one that can't is a hot pot with griddle. It draws 2000 watts.

Two fun facts about that:
1) it's still higher than 80% of a 20 amp circuit

2) I don't use it in my bedroom

 

[kwired]

mostly when vacuuming, because they tend to turn on all of the lights.

Haven't seen them tripping breakers for the most part in that situation but rather having issues with other items on the circuit because of voltage drop when the vacuum is running. 30 some years ago seen a television that the display went wacky whenever vacuum was used on same circuit - 15 amp circuits involved on that one - on top of that it was mobile home and possibly had some poor connections in those self contained devices you didn't need a separate outlet box for. Today cheap LED lights might not like voltage drop - even if it is deemed an acceptable level.

 

[andyman]

I think what it comes down to is that 15A receptacle circuits are inferior, especially if they are sharing the load with anything other than just recpt. If electricians wire 20A #12 receptacle circuits you will likely not have any nuisance tripping because of someone plugging in a vacuum or if the exterior receptacles get used for someones EV or whatever skill saw or something like that. You can still use 15A receptacles on a 20A circuit, that's the way I do it.

 

[James L]

I think what it comes down to is that 15A receptacle circuits are inferior, especially if they are sharing the load with anything other than just recpt. If electricians wire 20A #12 receptacle circuits you will likely not have any nuisance tripping because of someone plugging in a vacuum or if the exterior receptacles get used for someones EV or whatever skill saw or something like that. You can still use 15A receptacles on a 20A circuit, that's the way I do it.

Of course 15 is inferior to 20
And 20 is inferior to 30

I think this business about nuisance tripping is boogeyman myth stuff. It can happen, but nowhere near what the sensationalist over-reactionaries would have us believe.

One time a lady told me that when she plugs in her vacuum by the bed it trips the breaker. But if she plugs it in by the door it doesn't. My advice? Don't plug it in by the bed

 

[andyman]

Of course 15 is inferior to 20
And 20 is inferior to 30

Right, but the argument seems to be that 15A receptacle circuits are just as good as 20A which myself and others have found to not be the case. I am not ok with getting a call after completing a project with a customer having problems with our install. If I wire your house and you are tripping breakers I feel obligated to find a solution. Unless of coarse you are doing something out of the ordinary. If you call me because your vacuum trips a circuit when you plug in next to the bed I'm going to go out and take the receptacle out and find our why that is happening.
If they made a 30A receptacle that was configured for 15A cord ends that could be best

 

[LarryFine]

If they made a 30A receptacle that was configured for 15A cord ends that could be best

The receptacle and its ampacity itself is not part of the problem we're discussing.

Plug-in loads have changed over the years. Most receptacles were "lighting outlets" decades ago.

Now we have loads in living rooms, dens, bedrooms, etc., that we never imagined years ago.

 

[nizak]

Right, but the argument seems to be that 15A receptacle circuits are just as good as 20A which myself and others have found to not be the case. I am not ok with getting a call after completing a project with a customer having problems with our install. If I wire your house and you are tripping breakers I feel obligated to find a solution. Unless of coarse you are doing something out of the ordinary. If you call me because your vacuum trips a circuit when you plug in next to the bed I'm going to go out and take the receptacle out and find our why that is happening.
If they made a 30A receptacle that was configured for 15A cord ends that could be best

 

[VirutalElectrician]

Even with all 15a circuits, dividing the lights and receptacles onto separate circuits would help.

This. In fact, I've often wondered why it isn't code. Stumbling around in the dark because your appliance tripped a breaker kinda sucks.

 

[LarryFine]

This. In fact, I've often wondered why it isn't code. Stumbling around in the dark because your appliance tripped a breaker kinda sucks.

Exactly the reasoning behind separate receptacle circuits in kitchens, baths, garages, etc.

 

[ptonsparky]

The receptacle and its ampacity itself is not part of the problem we're discussing.

Plug-in loads have changed over the years. Most receptacles were "lighting outlets" decades ago.

Now we have loads in living rooms, dens, bedrooms, etc., that we never imagined years ago.

What are they? Everything in my household draws less current than it did 20 years ago. (No portable electric heaters.)

 

[kwired]

What are they? Everything in my household draws less current than it did 20 years ago. (No portable electric heaters.)

We have things we never imagined, no significant load for a majority of it though.

 

[James L]

I think the only thing I've seen in a bedroom that would overwhelm a 15 amp circuit was an elliptical machine.

But I'm not wiring a fitness center. I'm wiring a house. They can pay for a dedicated circuit for that machine if they want one

 

[LarryFine]

What are they?

I'm not suggesting we should necessarily wire bedrooms like kitchens, I'm just comparing the electrical loads we plug in now to the past, when a bedroom had maybe a ceiling light, a clock, and one or two lamps.

For example, in my bedroom, I have a 56" TV, a FIOS DVR, a stereo system, a DVD player, a halogen lamp (w/LED bulb), a floor fan, two clocks, a laptop computer, three USB chargers, plus a ceiling light/fan.

My son and his girlfriend are staying here for a while, and they have a mini-fridge, a hot-plate, a large TV, a computer system, a gaming system or two, a box fan, their USB phone chargers, and two or three lights.

Other homeowners may convert a spare bedroom into a home office complete with a full computer system w/printer, or a home-theater/media-room/game-room with an audio/video system approaching mine.

My point is that we use much more power these days than we did years ago, when we started with a single 30a circuit for entire homes, followed by 60a fused services with four 120v circuits for the entire house.

 

[readydave8]

I haven't been seeing problems with vacuums plugged in to 15 amp circuits, just space heaters and kitchens with many portable appliances and few circuits (usually 20 amp in kitchen)

 

[LarryFine]

I haven't been seeing problems with vacuums plugged in to 15 amp circuits . . .

I certainly have, such as at my brother's house.

As I said, all the lights and the vacuum, and poof!

 

[norcal]

I certainly have, such as at my brother's house.

As I said, all the lights and the vacuum, and poof!

Dyson & AFCI's?

 

[LarryFine]

Dyson & AFCI's?

No, construction in the late '70s; just too few circuits.

 

[Rick 0920]

No, construction in the late '70s; just too few circuits.

The NEC is minimum standards. The very LEAST we can do to get by. Take a 3,000 sq.ft. house for example. Figure 3va per sq. ft. for your 15A circuits to calculate your minimum number of branch circuits. 3,000 x 3va = 9,000 divided by 15a x 120 = 1800
9,000 divided by 1800 = 5!!!!! Who would only put (5) 15A circuits in a 3,000 sq.ft. house for lighting and general use receptacles????
If we wire buildings according to minimum standards, we SHOULD expect minimum results.

 

[ptonsparky]

If you charge minimum, build minimum