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15 vs 20 amp circuits

That would almost make sense if circuits always remained in the same
usage and with the same loads on them. When someone decides they need to
add something to the circuit or upgrade lighting things can change
dramatically and the 14ga circuit that was feeding the old circular
flouro in the kitchen may suddenly be feeding several halogen populated
cans and a pile of halogen under cabinet and soffit lighting in a
kitchen remodel.

Obviously one should take into account potential expansion, but that's
not a good reason to overdo *everything*. You're basically repeating
an extremely overused Usenet argument - "what about the next guy".
Doesn't make any sense in a lot of cases. For example, I have
something like 2 dozen pot lights, each on it's own circuit. If this
house ever has another owner, and they decide to add outlets into the
ceiling and plug in 100 times the wattage on some of those circuits...
But wait... isn't it just as likely that the next guy will end up in a
wheelchair? We should build ramps, etc.
I've never hear that, and can't even fathom the (il)logic behind it.

You might do some simple experiments with #12 and #14 wire. Pretend
you're a novice, and nick the wire when you strip it. Wrap it around a
screw connection, and then bend it back and forth like a novice does
when he's learning why he shouldn't try to stuff 5' of wire in a 1'
box. :) You'll find that the 14 breaks easier than the 12.
Perhaps, but I don't think the cost difference is that significant, even
with a complete home since you still can't use 14ga everywhere.

I probably used 1500 ft. of 14, and a lot less of everything else.
Everybody giving advice has something they think is worth "just a few
extra bucks", or "just a little extra work".

Wayne
 
X

xPosTech

Jan 1, 1970
0
Obviously one should take into account potential expansion, but that's
not a good reason to overdo *everything*. You're basically repeating
an extremely overused Usenet argument - "what about the next guy".
Doesn't make any sense in a lot of cases. For example, I have
something like 2 dozen pot lights, each on it's own circuit. If this
house ever has another owner, and they decide to add outlets into the
ceiling and plug in 100 times the wattage on some of those circuits...
But wait... isn't it just as likely that the next guy will end up in a
wheelchair? We should build ramps, etc.


Wayne

What are you growing under those pot lights? ;)
--
Ted
I wasn't born in Texas but
I got back here as soon as I could


Quondo Omni Flunkus Mortati (When All Else Fails, Play Dead.)
 
N

no spam

Jan 1, 1970
0
That's not a problem with the solution, it's a problem with the
I actually bought an old house and rewired it to my satisfaction, only
to find that the previous owner, a knowledgeable individual IMO, had
someone helping him (teenage son probly) who had wired outlets by pushing
the wires into the little slots instead of the holes on those cheap
push-in receptacles! I guess you'd call him Joe Bozo, Jr.

I've got a good one. I discovered, BEFORE I connected the power to the
breaker box, that someone connected the 220V water heater by using 2 15A
breakers. Really confused me when I had an extra breaker in the box.
 
N

no spam

Jan 1, 1970
0
I'd love to hear your explanation of how this will "blow stuff up."
If Joe Bozo homeowner doesn't have enough sense to turn the breaker off
before
he sets about replacing the receptacle, and doesn't pay any attention to
which
wires go where -- there are much larger problems than having an Edison
circuit
in the box.


That's just nonsense. Having only 120V present in the box does nothing to
eliminate the risk caused by homeowners who are stupid enough to work on
live
circuits without knowing what they're doing.

You're seeing the wrong problem here.

I wouldn't expect to need to flip two breakers to kill a single outlet. I'd
discover it because I check to see if the wires are hot after I flip a
breaker and before I start messing around with things. A multimeter, neon
tester or if all fails I short the wires I would rather have a shower of
sparks than get 'bitten'.
 
D

Doug Miller

Jan 1, 1970
0
I wouldn't expect to need to flip two breakers to kill a single outlet.

And you wouldn't need to, if the circuit was installed in compliance with the
NEC -- which *requires* a double-pole breaker if both legs are connected to
the same device.
 
C

clare at snyder.on.ca

Jan 1, 1970
0
More typically, I'm the first guy, and a few years later, the next guy.
I'm just as likely to expand or add something as some future owner. As
for the ramp thing, there are plenty of folks pushing for all new
construction to include such things. I don't agree with them by a long
shot, but ramps do come in handy for us otherwise able bodied folks who
tend to move a lot of heavy stuff around.
But ramps are DEADLY for the able-bodies with freezing rain and other
such icy crap we get up here.
 
More typically, I'm the first guy, and a few years later, the next guy.
I'm just as likely to expand or add something as some future owner.

Are you saying that you don't have *any* low-power circuits that won't
ever be changed?
I don't have any 14 ga solid wire. Everything I do is 12 ga or larger.

You shouldn't even need to do the experiment to know that the same
reason 14 is easier to handle makes it easier to break.
If you used that much 14 ga, you presumably have a larger than average
house,

2000 sq.ft, with an equal-sized attached shop. Everything on one
level. Lots of lighting circuits, all one light per circuit.
Highest-draw lighting fixtures are several rarely-used double
floodlights around the perimeter, 150W each.
a poorly located main panel,

Two centrally-located panels.
or other unusual configuration of
things.

It's easy to use a lot of wire in a new home, especially if you're
fond of home runs. I'm a fan of doing things that are useful and make
sense. Using #12 on low-power circuits isn't worth wasting money on,
particularly if it's borrowed money. It may seem like a small thing,
but by the time most people have paid off their home loan, they'll
have worked at least an extra week to pay for that wasted copper.
Anybody who can't think of something better to do with that week or
the income, should seek suggestions on Usenet. :)

Wayne
 
S

Smitty Two

Jan 1, 1970
0
Are you saying that you don't have *any* low-power circuits that won't
ever be changed?


You shouldn't even need to do the experiment to know that the same
reason 14 is easier to handle makes it easier to break.


2000 sq.ft, with an equal-sized attached shop. Everything on one
level. Lots of lighting circuits, all one light per circuit.
Highest-draw lighting fixtures are several rarely-used double
floodlights around the perimeter, 150W each.


Two centrally-located panels.


It's easy to use a lot of wire in a new home, especially if you're
fond of home runs. I'm a fan of doing things that are useful and make
sense. Using #12 on low-power circuits isn't worth wasting money on,
particularly if it's borrowed money. It may seem like a small thing,
but by the time most people have paid off their home loan, they'll
have worked at least an extra week to pay for that wasted copper.
Anybody who can't think of something better to do with that week or
the income, should seek suggestions on Usenet. :)

Wayne

I'm confused. You have a separate circuit for every light? And you scoff
at people who waste copper? I must've misunderstood some part of this.
 
I'm confused. You have a separate circuit for every light? And you scoff
at people who waste copper? I must've misunderstood some part of this.

We live off-grid. That means we have to be frugal with electricity.
For example, at our last place (on-grid), the living room had five 75W
incandescent pot lights, all on one dimmer switch. Our present living
room has three 12W CF pot lights, each with it's own switch. The
breaker panels were located so that the heavy wire runs were short,
main panel runs to the welders and air compressor are only about 10'.
Subpanel runs to the kitchen are about 20'. Next largest load in the
house are the 700W 230V heat pumps. Triple runs (one for each
inverter) to the office and home theater areas. So, like many custom
homes, we did use a lot of wire, but it was mostly #14 which I bought
on sale for $13 per 250' roll (12 years ago). Floor plan here
http://www.citlink.net/~wmbjk/images/main/floorplan.jpg. Main panel is
in the garage on the wall behind the car. Subpanel is in the living
room on the backside of the kitchen wall. BTW, the inverter that
serves most of the home theater stuff plus 3 computers, is only 500W.
It would have been a bit silly to divide that up into multiple runs of
#12. And all of those components would use the same power if they were
on-grid.

Wayne
 
C

Chris Lewis

Jan 1, 1970
0
According to Pete C. said:
Chris Lewis wrote:
[Not counting builtin microwave either - that's supposed to be a dedicated
circuit, just like yours. Doesn't have to be 20A tho. Fridge, garburator,
dishwasher each a dedicated circuit too. With some minor permissible addons
(clocks etc). CEC is stricter on dedicated kitchen circuits than the NEC.
Or at least it was.]
It's not really a built in microwave, just a dedicated shelf space for a
regular one. Fridge is indeed another separate 20A circuit. Disposal and
dishwasher each share (separately) one of the 20A circuits feeding a
"quad".

They're required to be dedicated circuits here (DW officially, disposal
"usually"), and you can't share kitchen counter outlets with anything
else regardless.

The older "split receptacle" requirement was that you could put
at most two split duplex receptacles on a dual breaker, you
couldn't put the two split receptacles adjacent to each other on
a counter, and every kitchen had to have at least two splits.
Eg: on a short counter requiring two receptacles, they had to be
different dual circuits. I assume they're doing the same thing
with the new single 20A/GFCI version.
I like my quads, particularly with the fixed use items in my kitchen
that take up outlets - wall wart for cat water fountain dish, wall wart
for cordless phone base, and night light - there go three outlet spaces
right there.

That's what "hexes" are for ;-) [6-way receptacle blocks that
plug into a receptacle.]

They have the advantage of not being there if you don't need 'em. Most
(all?) are even compatible with split duplex receptacles -> meaning
three outlets each on two circuits.
 
C

Chris Lewis

Jan 1, 1970
0
According to said:
You are correct. But I stand by my statement - 220 is NO SURPRISE if
you have both a red and a black wire.

I'm going to suggest a slight rephrase:

220 SHOULD be no surprise if you have both a red and black wire.

If it is a surprise, you have no business futzing with wiring.

[In realith, 220 shouldn't be a surprise even if you only have
a black and white wire. Think 220-only circuits. Like electric
baseboards and perfectly legal practise of using ordinary wire,
rather than the somewhat less common black+red+ground/no white
wire.]
 
C

Chris Lewis

Jan 1, 1970
0
According to said:
How do u tell if u have 15a outlets and/or breakers. Can u use a
multimeter to determine amperage?

The breaker has the amperage stamped on it (usually the handle). The
breaker amps should NEVER (at least in most residential circumstances)
exceed the rating of the wire.

Wire usually has the wire size stamped on it, if it doesn't,
you can tell whether the conductors are 14ga (15A) or 12ga (20A)
simply by comparing it to a known piece of wire.

There's three kinds of outlets you might encounter:

1 The 20A kind you can't plug a 15A plug into (one blade is turned
90 degrees), and only accepts 20A plugs.
2 A different 20A kind has a "t-slot", which will accept both 20A
and 15A plugs.
3 Ordinary 15A outlets (that won't accept a "true" 20A plug). These
outlets are actually rated for 20A - you can draw a total of
20A from the receptacle (if the breaker will allow it), but no
more than 15A from either outlet. Which means you can install
these on 20A circuits, but the devices you plug into it are limited
to 15A plugs.

[In other words, all permissible to connect on a 20A circuit.]

In the US, where 20A general purpose receptacle circuits are legal,
most are wired with outlet (3) only. 20A plug devices are rare.
In those rare cases where it's likely that a true 20A device is
required, you use a T-slot receptacle (2). You won't see (1) on
general purpose circuits - they're primarily for dedicated 20A
appliances.

In Canada, until quite recently, general purpose 20A circuits were
essentially illegal, because (2) simply were never approved for sale.
The only 20A/120V circuits you see were for dedicated equipment,
usually direct-wire. As such, 120V/20A outlets (1) are extremely
rarely used. I've never seen one in residential wiring, only in
workshops and industrial situations for power tools.

I don't think I've ever seen a T-slot outlet in use in Canada, except
for a couple archeological finds that predate plugs with ground pins.
This'll change with the latest amendments to the CEC.
 
C

Chris Lewis

Jan 1, 1970
0
According to said:
It's easy to use a lot of wire in a new home, especially if you're
fond of home runs. I'm a fan of doing things that are useful and make
sense. Using #12 on low-power circuits isn't worth wasting money on,
particularly if it's borrowed money. It may seem like a small thing,
but by the time most people have paid off their home loan, they'll
have worked at least an extra week to pay for that wasted copper.

Ectually, I'd consider putting two dozen single low-moderate wattage
fixtures on individual dedicated/homerunned 15A circuits to be a vastly
greater waste of money than picking 12ga over 14ga, but perhaps that's
just me.

You probably could have put all of the fixtures on a handful
of daisy-chained 15A circuits or even 12ga/20A circuits and
saved a heck of a lot more than picking 14ga over 12ga.
 
C

Chris Lewis

Jan 1, 1970
0
According to said:
On Wed, 26 Sep 2007 19:09:03 -0700, Smitty Two
We live off-grid. That means we have to be frugal with electricity.
For example, at our last place (on-grid), the living room had five 75W
incandescent pot lights, all on one dimmer switch. Our present living
room has three 12W CF pot lights, each with it's own switch.

That still doesn't mean that each CF pot has to have to have its own
circuit, _unless_ you plan on automated centralized control of
individual devices by the brute-force method of switching their circuits
on and off. Whether or not two fixtures are on the same or different
circuits is irrelevant to frugality. There are cheaper/more effective
ways of lamp control. Like the switches you have on each.
 
S

Smitty Two

Jan 1, 1970
0
We live off-grid. That means we have to be frugal with electricity.
For example, at our last place (on-grid), the living room had five 75W
incandescent pot lights, all on one dimmer switch. Our present living
room has three 12W CF pot lights, each with it's own switch. The
breaker panels were located so that the heavy wire runs were short,
main panel runs to the welders and air compressor are only about 10'.
Subpanel runs to the kitchen are about 20'. Next largest load in the
house are the 700W 230V heat pumps. Triple runs (one for each
inverter) to the office and home theater areas. So, like many custom
homes, we did use a lot of wire, but it was mostly #14 which I bought
on sale for $13 per 250' roll (12 years ago). Floor plan here
http://www.citlink.net/~wmbjk/images/main/floorplan.jpg. Main panel is
in the garage on the wall behind the car. Subpanel is in the living
room on the backside of the kitchen wall. BTW, the inverter that
serves most of the home theater stuff plus 3 computers, is only 500W.
It would have been a bit silly to divide that up into multiple runs of
#12. And all of those components would use the same power if they were
on-grid.

Wayne

Looks good. But, a light switch and a circuit are two different things.
Are you building the plane, too, or is that store bought?
 
C

clare at snyder.on.ca

Jan 1, 1970
0
Yes there is - starting a vacuum cleaner on one leg stresses the
lights on the other leg. Probably not to nice for electronic devices
either.
Red herring. EVERY circuit in the VAST majority of North American
homes is on an "edison circuit" - just not both sides in one box.
Done with any level of competency at all what you envision is no
problem at all.
 
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