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OT: Kitchen appliance weirdness...

D

Don Y

Guest
On 8/26/2020 4:29 PM, Tabby wrote:
On Tuesday, 25 August 2020 21:00:00 UTC+1, Don Y wrote:

That may be yet another difference in our markets. Here, most small
appliances *tend* to max out at around 1000W (that\'s not to say you can\'t
find ones that consume more!). Hair dryers, toasters, microwave ovens,
etc. So, most have little 16AWG power cords as they\'re only handling
~8A.

The toasters drew 15A at 240v, being made in the time of round pin 15A
plugs. Our plugs today are 13A rated = 3.1kW.
Yikes! My electric clothes dryer is fused at just twice that -- and I assume
it has to put out a sh*tload more BTUs!

60 acbrr
50 oven
30 dryer
20 cooler

20 furnace
20 refrig

Many smaller houses wired in the 70s often have all the sockets on one
single circuit. Yep, all. 2 circuits is most common. They\'re 7kW circuits.
A modest home, here, will likely have a 100A service (@240VAC). This will
be broken into a couple dozen individual branch circuits. Most will be
120V circuits -- though larger devices (AC compressor @ 60A, electric
oven/stove @ 50A, electric clothes dryer @ 30A) will get 240V feeds.

There are other 20A GFCI circuits \"required\": garage, outdoors, bathrooms.

The 120V circuits are either 15A or 20A and are usually derated to 80%.
So, you\'d typically have ~1440W available to be shared among a pair of
bedrooms. (this isn\'t usually a problem -- unless you have \"window units\"
for ACbrrr)

Some loads have dedicated circuits (required or for convenience): furnace,
refrigerator, evaporative cooler, AC compressor, stove/oven, etc.

The kitchen is inevitably the biggest power sink INSIDE the house. In
addition to the two 20A GFCI\'s mandated, there will be circuits for dishwasher,
garbage disposal, refrigerator, oven/stove, exhaust fans, \"instant\" hot
water, microwave, etc. (toaster uses a countertop circuit).

And, if you\'re not keen on having to reset tripped breakers because you
\"ran the disposal\" while the microwave was on and the refrigerator\'s
compressor cycled, you distribute the loads judiciously. E.g., we have
five 20A circuits (in addition to the oven/stove) in our modest kitchen.
(we can literally run \"everything\" without tripping a breaker).
 
T

Tabby

Guest
On Thursday, 27 August 2020 01:34:47 UTC+1, Don Y wrote:
On 8/26/2020 4:29 PM, Tabby wrote:
On Tuesday, 25 August 2020 21:00:00 UTC+1, Don Y wrote:

That may be yet another difference in our markets. Here, most small
appliances *tend* to max out at around 1000W (that\'s not to say you can\'t
find ones that consume more!). Hair dryers, toasters, microwave ovens,
etc. So, most have little 16AWG power cords as they\'re only handling
~8A.

The toasters drew 15A at 240v, being made in the time of round pin 15A
plugs. Our plugs today are 13A rated = 3.1kW.

Yikes! My electric clothes dryer is fused at just twice that -- and I assume
it has to put out a sh*tload more BTUs!

60 acbrr
50 oven
30 dryer
20 cooler

20 furnace
20 refrig

Many smaller houses wired in the 70s often have all the sockets on one
single circuit. Yep, all. 2 circuits is most common. They\'re 7kW circuits.

A modest home, here, will likely have a 100A service (@240VAC). This will
be broken into a couple dozen individual branch circuits. Most will be
120V circuits -- though larger devices (AC compressor @ 60A, electric
oven/stove @ 50A, electric clothes dryer @ 30A) will get 240V feeds.

There are other 20A GFCI circuits \"required\": garage, outdoors, bathrooms.

The 120V circuits are either 15A or 20A and are usually derated to 80%.
So, you\'d typically have ~1440W available to be shared among a pair of
bedrooms. (this isn\'t usually a problem -- unless you have \"window units\"
for ACbrrr)

Some loads have dedicated circuits (required or for convenience): furnace,
refrigerator, evaporative cooler, AC compressor, stove/oven, etc.

The kitchen is inevitably the biggest power sink INSIDE the house. In
addition to the two 20A GFCI\'s mandated, there will be circuits for dishwasher,
garbage disposal, refrigerator, oven/stove, exhaust fans, \"instant\" hot
water, microwave, etc. (toaster uses a countertop circuit).

And, if you\'re not keen on having to reset tripped breakers because you
\"ran the disposal\" while the microwave was on and the refrigerator\'s
compressor cycled, you distribute the loads judiciously. E.g., we have
five 20A circuits (in addition to the oven/stove) in our modest kitchen.
(we can literally run \"everything\" without tripping a breaker).
2 dozen circuits would mean an extensive house here. 2 whole floors off one or 2 socket circuits is common (plus typ 2 lighting ccts).

We\'re not allowed bathroom sockets other than a 20 watt transformer isolated supply for shaver/toothbrush.

100A 240v is as high as it gets for regular private houses. Small flats get 40A, there are still 30A places around. Last year checked out a mid sized uninsulated all-electric house still running off its prewar dual pole fused 30A service. Not acceptable.

In Russia lots of flats run on 8A single insulted earthless aluminium supplies. Italy can be stingy too, AIUI you pay for how much capacity you\'ve got, and it starts at, I forget, something like 10 or 15A.


NT
 
D

Don Y

Guest
On 8/26/2020 5:59 PM, Tabby wrote:
2 dozen circuits would mean an extensive house here. 2 whole floors off one
or 2 socket circuits is common (plus typ 2 lighting ccts).
Well, yeah! At 3KW per circuit, I\'d consider it a bit excessive! :>

We\'re not allowed bathroom sockets other than a 20 watt transformer isolated
supply for shaver/toothbrush.
Can you have outlets \"near\" the kitchen sink? Here, 12\" from water *and* GFCI
protected (I think that is now changing to AFCI). So, bathroom outlets are
located \"away\" from the sink.

100A 240v is as high as it gets for regular private houses. Small flats get
40A, there are still 30A places around. Last year checked out a mid sized
uninsulated all-electric house still running off its prewar dual pole fused
30A service. Not acceptable.
There are some \"all electric\" homes in the neighborhood -- air sourced heat
pumps, electric water heaters, electric clothes dryers, electric oven/stove.
They tend to have different tariffs in place (though I think the PUC has
been slowly phasing those out) to account for their \"costlier\" services.

[Most homes have a mixture of energy supplies -- electric, natural gas,
heating oil, coal, etc. -- so to be all-electric is a hefty SINGLE supply]

In Russia lots of flats run on 8A single insulted earthless aluminium
supplies. Italy can be stingy too, AIUI you pay for how much capacity you\'ve
got, and it starts at, I forget, something like 10 or 15A.
Yikes! I lived in a 60A (@240V) home for a while and found it tedious
to manage loads. We don\'t think twice about cooking while the refrigerator
may be cycling, AC compressor engaged (which means furnace/blower is on, as
well), several computers running, dishwasher running, electric clothes dryer
AND washer running, etc. In the winter, I\'ll dump a few KW in the citrus
trees to protect them from frost damage. <shrug> \"It\'s only money...\"

[We are really quite gluttonous in our power consumption :< ]
 
T

Tabby

Guest
On Thursday, 27 August 2020 02:56:22 UTC+1, Don Y wrote:
On 8/26/2020 5:59 PM, Tabby wrote:

2 dozen circuits would mean an extensive house here. 2 whole floors off one
or 2 socket circuits is common (plus typ 2 lighting ccts).

Well, yeah! At 3KW per circuit, I\'d consider it a bit excessive! :
240v 32A is 7.68kW per circuit. It\'s normal for that 32A to be exceeded by a fair margin when supplying an electric kitchen, but not for long. 32A is the continuous rating.

We\'re not allowed bathroom sockets other than a 20 watt transformer isolated
supply for shaver/toothbrush.

Can you have outlets \"near\" the kitchen sink? Here, 12\" from water *and* GFCI
protected (I think that is now changing to AFCI). So, bathroom outlets are
located \"away\" from the sink.
Yes, bathrooms are considered different because the lack of clothes plus wetness = more at risk

100A 240v is as high as it gets for regular private houses. Small flats get
40A, there are still 30A places around. Last year checked out a mid sized
uninsulated all-electric house still running off its prewar dual pole fused
30A service. Not acceptable.

There are some \"all electric\" homes in the neighborhood -- air sourced heat
pumps, electric water heaters, electric clothes dryers, electric oven/stove.
They tend to have different tariffs in place (though I think the PUC has
been slowly phasing those out) to account for their \"costlier\" services.

[Most homes have a mixture of energy supplies -- electric, natural gas,
heating oil, coal, etc. -- so to be all-electric is a hefty SINGLE supply]

In Russia lots of flats run on 8A single insulted earthless aluminium
supplies. Italy can be stingy too, AIUI you pay for how much capacity you\'ve
got, and it starts at, I forget, something like 10 or 15A.

Yikes! I lived in a 60A (@240V) home for a while and found it tedious
to manage loads. We don\'t think twice about cooking while the refrigerator
may be cycling, AC compressor engaged (which means furnace/blower is on, as
well), several computers running, dishwasher running, electric clothes dryer
AND washer running, etc. In the winter, I\'ll dump a few KW in the citrus
trees to protect them from frost damage. <shrug> \"It\'s only money...\"

[We are really quite gluttonous in our power consumption :< ]
60A is as much as any non-huge house ever needs here.

Worst I ever saw was some flats in the 90s each on an ancient 5A feed. It was workable, albeit a pain. Write the current consumption of each appliance on the plug, and you know your limit. The supplied appliances were equally ancient.


NT
 
D

Don Y

Guest
On 8/27/2020 8:10 AM, Tabby wrote:
On Thursday, 27 August 2020 02:56:22 UTC+1, Don Y wrote:
On 8/26/2020 5:59 PM, Tabby wrote:

2 dozen circuits would mean an extensive house here. 2 whole floors off
one or 2 socket circuits is common (plus typ 2 lighting ccts).

Well, yeah! At 3KW per circuit, I\'d consider it a bit excessive! :

240v 32A is 7.68kW per circuit. It\'s normal for that 32A to be exceeded by a
fair margin when supplying an electric kitchen, but not for long. 32A is the
continuous rating.
So where does the 13A come in? Is that the \"per appliance\" limit?

We\'re not allowed bathroom sockets other than a 20 watt transformer
isolated supply for shaver/toothbrush.

Can you have outlets \"near\" the kitchen sink? Here, 12\" from water *and*
GFCI protected (I think that is now changing to AFCI). So, bathroom
outlets are located \"away\" from the sink.

Yes, bathrooms are considered different because the lack of clothes plus
wetness = more at risk
So, to dry your hair (1KW), you\'d have to do that elsewhere?

Yikes! I lived in a 60A (@240V) home for a while and found it tedious to
manage loads. We don\'t think twice about cooking while the refrigerator
may be cycling, AC compressor engaged (which means furnace/blower is on,
as well), several computers running, dishwasher running, electric clothes
dryer AND washer running, etc. In the winter, I\'ll dump a few KW in the
citrus trees to protect them from frost damage. <shrug> \"It\'s only
money...\"

[We are really quite gluttonous in our power consumption :< ]

60A is as much as any non-huge house ever needs here.
What\'s \"non huge\"? Our home isn\'t what we\'d consider \"huge\" (3BR).
I know folks who live in places that you could get LOST in! :<

Worst I ever saw was some flats in the 90s each on an ancient 5A feed. It
was workable, albeit a pain. Write the current consumption of each appliance
on the plug, and you know your limit. The supplied appliances were equally
ancient.
Air conditioning is the big killer in most places that I\'ve lived.
As it\'s inconvenient to (manually) \"switch off\" in order to shed load,
you have to assume its running almost always.

There are still places, here, with K&T wiring. But, that is usually
supplemented by more modern additions to service. Too many \"things\"
eating too much *power*!

Many of our neighbors have 200A services (same size homes).
 
T

Tabby

Guest
On Thursday, 27 August 2020 16:33:58 UTC+1, Don Y wrote:
On 8/27/2020 8:10 AM, Tabby wrote:
On Thursday, 27 August 2020 02:56:22 UTC+1, Don Y wrote:
On 8/26/2020 5:59 PM, Tabby wrote:

2 dozen circuits would mean an extensive house here. 2 whole floors off
one or 2 socket circuits is common (plus typ 2 lighting ccts).

Well, yeah! At 3KW per circuit, I\'d consider it a bit excessive! :

240v 32A is 7.68kW per circuit. It\'s normal for that 32A to be exceeded by a
fair margin when supplying an electric kitchen, but not for long. 32A is the
continuous rating.

So where does the 13A come in? Is that the \"per appliance\" limit?
Mains plugs are 13A rated, 13A fused. They plug into usually 32A ring circuits, less often 20A radials.

Appliances with 2 mains leads are a rarity, but they do exist. Expect to never see one though. Typically a tiny minority of hire tools.

We\'re not allowed bathroom sockets other than a 20 watt transformer
isolated supply for shaver/toothbrush.

Can you have outlets \"near\" the kitchen sink? Here, 12\" from water *and*
GFCI protected (I think that is now changing to AFCI). So, bathroom
outlets are located \"away\" from the sink.

Yes, bathrooms are considered different because the lack of clothes plus
wetness = more at risk

So, to dry your hair (1KW), you\'d have to do that elsewhere?
of course. Unless you\'re very very patient :) Perhaps 20w would electrolyse the water off.


Yikes! I lived in a 60A (@240V) home for a while and found it tedious to
manage loads. We don\'t think twice about cooking while the refrigerator
may be cycling, AC compressor engaged (which means furnace/blower is on,
as well), several computers running, dishwasher running, electric clothes
dryer AND washer running, etc. In the winter, I\'ll dump a few KW in the
citrus trees to protect them from frost damage. <shrug> \"It\'s only
money...\"

[We are really quite gluttonous in our power consumption :< ]

60A is as much as any non-huge house ever needs here.

What\'s \"non huge\"? Our home isn\'t what we\'d consider \"huge\" (3BR).
I know folks who live in places that you could get LOST in! :
100A is plenty for a large 5 bed. Not for a place with 20 beds though.


Worst I ever saw was some flats in the 90s each on an ancient 5A feed. It
was workable, albeit a pain. Write the current consumption of each appliance
on the plug, and you know your limit. The supplied appliances were equally
ancient.

Air conditioning is the big killer in most places that I\'ve lived.
As it\'s inconvenient to (manually) \"switch off\" in order to shed load,
you have to assume its running almost always.
Yeah, we seldom have ac, and when we do we don\'t need a lot of power for it..

There are still places, here, with K&T wiring. But, that is usually
supplemented by more modern additions to service. Too many \"things\"
eating too much *power*!

Many of our neighbors have 200A services (same size homes).
All our rubber 1950s wiring rotted away long ago. Must be different rubber formulation, there\'s none left in service that I know of. I remember looking at some in the 1980s, twisted pair in iron conduit as was very common then. The insulation had all fallen off from the foot or so I could see, the wires snaking round each other in mid air. Owner had no intention of rewiring.

The last holdout I knew of was rewired a few years ago, way overdue. I gather K&T is perfectly capable.

We\'ve still got lots of prewar supply systems though, there was a huge electrification drive in the 1930s.


NT
 
M

Michael_A_Terrell

Guest
Tabby wrote:
Worst I ever saw was some flats in the 90s each on an ancient 5A feed. It was workable, albeit a pain. Write the current consumption of each appliance on the plug, and you know your limit. The supplied appliances were equally ancient.
That reminds me of a \'60s TV Sitcom, \'Green Acres\' where the husband
is trying to explain the maximum power their run down farm\'s old
generator could put out without shutting down.

After my recent electrical damage, I only have one working 20A 120
Volt circuit in the house. I will be thrilled when the repairs are
finished. It lets me have a few lights, a 5,000 BTU A/C and a small
computer.


--
Never piss off an Engineer!

They don\'t get mad.

They don\'t get even.

They go for over unity! ;-)
 
M

Michael_A_Terrell

Guest
Tabby wrote:
All our rubber 1950s wiring rotted away long ago. Must be different rubber formulation, there\'s none left in service that I know of. I remember looking at some in the 1980s, twisted pair in iron conduit as was very common then. The insulation had all fallen off from the foot or so I could see, the wires snaking round each other in mid air. Owner had no intention of rewiring.
K&T used tar covered with a woven cotton tube to secure it. It is
quite stable, as long as it doesn\'t get a lot of flexing as it ages. I
had to replace the wiring harness in a 1952 RCA TV transmitter. You
could hear the dried out rubber cracking with the slightest flexing. It
had caused one exciter to catch fire. Luckily, the TTU1 transmitter was
the exciter for the TTU25B, and they located an even older replacement.
I used THHN for the new harness.



--
Never piss off an Engineer!

They don\'t get mad.

They don\'t get even.

They go for over unity! ;-)
 
T

Tom Del Rosso

Guest
Don Y wrote:
On 8/23/2020 8:39 AM, amdx wrote:

I saw a 2 for 1 sale on Bottom round, so I tried Sous Vide on it. I
sliced it in 1\" thick pieces, seasoned it, bagged each piece
separately and
cooked it for 18 hrs.

Wow! It takes THAT long? Have you played with the temperature
setting to see if you can trade time for quality/taste? E.g., how
much faster you could finish at ~150F and whether or not there would
be any differences in taste/texture?
It would be well-done. Medium rare is about 135F. Sous vide requires a
cooking temperature equal to the target temperature.
 
T

Tom Del Rosso

Guest
amdx wrote:
I setup a temporary Sous Vide with a temp controller (STC-1000). I
used a single burner with a large pot of water on top.

When I started, the burner turn on would overshoot my set temperature
of 137*F
by about 12*F. I added an 8 ohm resistor in series with the burner and
lowered the over shoot to about 2*F.

I saw a 2 for 1 sale on Bottom round, so I tried Sous Vide on it. I
sliced it in 1\" thick pieces, seasoned it, bagged each piece
separately and cooked it for 18 hrs. I froze all the
bags, then when I want a quick piece of beef, I quickly thaw it in hot
water and brown it in a pan with some olive
oil. It turned out pink and tender. I\'ll do it again.
Bottom round must be tough in thick slices. Shoulder london broil would
be more tender.

I do beef roasts on the stove top to sear all sides, then roast at
175-200F for about 4 hours, checking with a thermometer every 15 minutes
near the end. I think the result is very similar with a very thin brown
layer between the pink and the sear.
 
D

Don Y

Guest
On 8/28/2020 7:47 PM, Tabby wrote:

So where does the 13A come in? Is that the \"per appliance\" limit?

Mains plugs are 13A rated, 13A fused. They plug into usually 32A ring
circuits, less often 20A radials.
But not EVERY device is fused at 13A; 13A is the MAX that a plug can
be fused? I.e., you wouldn\'t fuse a table lamp at 13A... (we wouldn\'t fuse
a table lamp but would rely on the branch circuit\'s fusing to limit current
in a fault)

Assuming each device is fused at a size appropriate for the load it
represents, is there something that prevents a user from replacing the
fuse with one of higher rating?

All the plugs (and receptacles) are the same? So, there is nothing
that prevents a user from plugging into a \"too small ampacity\" circuit?
(i.e., all yours are 32A so that likely ensures circuit is larger
than any load).

I.e., would you plug an electric stove into the mains with the same
plug/outlet? (our stove/oven is fused for 50A@240VAC)

A typical US consumer will deal with maybe 5 or 6 different types
of receptacles (and, thus, plugs):
- unpolarized 2 prong (increasingly rare)
- polarized 2 prong (insulated devices not needing earth connection)
- 3 prong (120VAC+earth)
- 3 prong, 20A (neutral blade is orthogonal to hot blade: |-)
- 3 or 4 prong, 220V, 30A (clothes dryer)
- 3 or 4 prong, 220V, 50 or 60A (stove)
It is not possible, for example, to plug my clothes dryer into the outlet
for the oven -- even though the oven\'s branch circuit has a higher
ampacity. Likewise, my 12AWG extension cord bears a 20A plug (|-)
which makes it incompatible with most 15A receptacles (||).

Appliances with 2 mains leads are a rarity, but they do exist. Expect to
never see one though. Typically a tiny minority of hire tools.
That\'s a way around the ampacity limitation? E.g., here, two leads would
only be used for things that have \"backup\" power needs (e.g., servers).
If you needed more ampacity than a 15A (or 20A) circuit, you\'d run a
new branch circuit with the desired ampacity (typically also a 240V branch
circuit when loads get to be that big).

60A is as much as any non-huge house ever needs here.

What\'s \"non huge\"? Our home isn\'t what we\'d consider \"huge\" (3BR). I know
folks who live in places that you could get LOST in! :

100A is plenty for a large 5 bed. Not for a place with 20 beds though.
100A is \"comfortable\", here (as I said, we tend to be gluttons and don\'t
consider \"managing\" our loads).

You may have a whirlpool/jacuzzi bathtub (pump to circulate water),
a swimming pool, an outdoor spa/jacuzzi (circulation pump and heater!),
dual refrigerator, dedicated freezer, etc. So, a *200A* service isn\'t
necessarily a \"luxury\".

[larger homes often have several HVAC plants, pool, spa, etc.]

And, devices don\'t coordinate their power use so there\'s nothing to prevent
them from all TRYING to use whatever power they need (the consumer is
eventually conditioned against doing this by a circuit breaker repeatedly
tripping -- and his remedy is to add more capacity! :< )

Residences usually have few tariff options (ways that they can be billed).
Here, our only real choice (neglecting impact of solar cogeneration on tariff)
is ToU (Time of Use) metering. But, given our high DAYTIME energy requirement
for cooling, it is a losing proposition for almost every homeowner.

Businesses tend to have different tariffs that can motivate them to more
actively manage their consumption. E.g., *peak* (demand) metering effectively
bills them for energy AS IF it was continuously being used at it\'s peak
measured rate. So, they have a big incentive to do load leveling and
time shifting.

For example, a hotel would typically network the individual HVAC units
placed in each guest room to stagger when they can each DEMAND power
(so, even though the device appears to come on when the guest tweaks the
temperature setting, it may not really be providing the heating/cooling
that is desired -- yet!). Occupancy sensors can shed loads when the
room is considered vacant.

Large businesses \"make ice\" at night in anticipation of the next day\'s
cooling load. They\'re effectively being billed for power they aren\'t
using, at night (shop is closed) so the recurring power cost is effectively
FREE! Instead, just pay for the non-recurring equipment costs!

Air conditioning is the big killer in most places that I\'ve lived. As it\'s
inconvenient to (manually) \"switch off\" in order to shed load, you have to
assume its running almost always.

Yeah, we seldom have ac, and when we do we don\'t need a lot of power for
it.
Prior to whole-house AC, we\'d use individual units \"per room\". A typical
bedroom would be served by a 5000BTU unit which would draw ~3-5A (depending on
its efficiency rating). You\'d place one in EACH bedroom and they would
each operate independent of each other (so, you could see a 15A load, at
times). You\'d put something larger in a kitchen area because:
- it\'s often fighting an additional heat source
- the area is more open than a bedroom (which has a door that can be closed)
And, something else for other \"living areas\", etc.

There are still places, here, with K&T wiring. But, that is usually
supplemented by more modern additions to service. Too many \"things\"
eating too much *power*!

Many of our neighbors have 200A services (same size homes).

All our rubber 1950s wiring rotted away long ago. Must be different rubber
formulation, there\'s none left in service that I know of.
Asphalt.

I remember looking
at some in the 1980s, twisted pair in iron conduit as was very common then.
The insulation had all fallen off from the foot or so I could see, the wires
snaking round each other in mid air. Owner had no intention of rewiring.
Many older homes used it. And, typically had uninsulated wall spaces (through
which the wiring would travel). The lower capacity and lack of insulation
conspire to coerce BUYERS of such properties to rewire (original occupant
may have just left it be)

The last holdout I knew of was rewired a few years ago, way overdue. I
gather K&T is perfectly capable.
Yes, just don\'t dick with it! :> I still have rolls of asphalt-impregnated
tape lying around...

We\'ve still got lots of prewar supply systems though, there was a huge
electrification drive in the 1930s.
By far, the more common \"legacy\" wiring is 2-wire \"BX\". The downside there
is the lack of reliable earth conductor at each Jbox/outlet.

The trend, here, is always towards \"more\" -- or <whatever>. E.g., new homes
now require 1\" copper water mains instead of the 3/4\" that was in use when
this home was built. Yet, water FIXTURES are sold with flow rate limiters!
<shakes head>
 
D

Don Y

Guest
On 8/29/2020 6:30 AM, Tom Del Rosso wrote:
Don Y wrote:
On 8/23/2020 8:39 AM, amdx wrote:

I saw a 2 for 1 sale on Bottom round, so I tried Sous Vide on it. I
sliced it in 1\" thick pieces, seasoned it, bagged each piece
separately and
cooked it for 18 hrs.

Wow! It takes THAT long? Have you played with the temperature
setting to see if you can trade time for quality/taste? E.g., how
much faster you could finish at ~150F and whether or not there would
be any differences in taste/texture?

It would be well-done. Medium rare is about 135F. Sous vide requires a
cooking temperature equal to the target temperature.
Yeah, I\'m still nervous about killing off pathogens...
 
K

keith wright

Guest
On Saturday, 29 August 2020 10:51:56 UTC-7, Don Y wrote:
On 8/28/2020 7:47 PM, Tabby wrote:

So where does the 13A come in? Is that the \"per appliance\" limit?

Mains plugs are 13A rated, 13A fused. They plug into usually 32A ring
circuits, less often 20A radials.

But not EVERY device is fused at 13A; 13A is the MAX that a plug can
be fused? I.e., you wouldn\'t fuse a table lamp at 13A... (we wouldn\'t fuse
a table lamp but would rely on the branch circuit\'s fusing to limit current
in a fault)
There are 2 or 3 standard fuses used depending upon the device. 2A, 5A and 13A or similar.
Assuming each device is fused at a size appropriate for the load it
represents, is there something that prevents a user from replacing the
fuse with one of higher rating?
Not in my experience, but I haven\'t lived there for a while. Devices with moulded plugs would still have the fuse replaceable.

All the plugs (and receptacles) are the same? So, there is nothing
that prevents a user from plugging into a \"too small ampacity\" circuit?
(i.e., all yours are 32A so that likely ensures circuit is larger
than any load).

I.e., would you plug an electric stove into the mains with the same
plug/outlet? (our stove/oven is fused for 50A@240VAC)
Stoves would be hard wired with their own circuit breaker.

Similarly for other high power devices such as electric showers or heating.

....
 
D

Don Y

Guest
On 8/29/2020 6:59 PM, keith wright wrote:
On Saturday, 29 August 2020 10:51:56 UTC-7, Don Y wrote:
On 8/28/2020 7:47 PM, Tabby wrote:

So where does the 13A come in? Is that the \"per appliance\" limit?

Mains plugs are 13A rated, 13A fused. They plug into usually 32A ring
circuits, less often 20A radials.

But not EVERY device is fused at 13A; 13A is the MAX that a plug can be
fused? I.e., you wouldn\'t fuse a table lamp at 13A... (we wouldn\'t fuse
a table lamp but would rely on the branch circuit\'s fusing to limit
current in a fault)

There are 2 or 3 standard fuses used depending upon the device. 2A, 5A and
13A or similar.
Do folks \"do stupid things\" like replacing a fuse that blows with a larger
one thinking that will \"solve\" The Problem? Or, do they have a \"proper
respect\" for that which they don\'t understand?

[I am assuming a table lamp would have a much lighter gauge cord than
a large appliance (?) so oversizing the fuse could be a hazard]

All the plugs (and receptacles) are the same? So, there is nothing that
prevents a user from plugging into a \"too small ampacity\" circuit? (i.e.,
all yours are 32A so that likely ensures circuit is larger than any
load).

I.e., would you plug an electric stove into the mains with the same
plug/outlet? (our stove/oven is fused for 50A@240VAC)

Stoves would be hard wired with their own circuit breaker.
While not a \"rule\", I think homes here tend to have outlets for almost
all devices, regardless of power consumption (circuit ampacity). This
makes it easy (low tech) to replace a stove/oven with a new one -- just
\"unplug\" the old and plug the new in its place.

E.g., none of our furnace, evap cooler, oven/stove, clothes dryer are
hard-wired. All have plugs/power cords. Though all have \"dedicated
circuits\" sized for their expected loads. This tends to be the case
even with things like garbage disposals (e.g., a switched outlet located
under the sink) and dishwashers.

[When one buys a major appliance, you often have to purchase the
power cord separately to ensure compatibility with your home.
Things like *cooktops* are often hardwired owing to the manner
in which they are installed. The same is probably true of ovens built
INTO walls]

I think our sole hard-wired device is the AC compressor and that may be
the case solely because it\'s easier to hardwire an outdoor installation
than to have to install a weatherproof outlet with rain cover.

> Similarly for other high power devices such as electric showers or heating.
 
K

keith wright

Guest
On Saturday, 29 August 2020 20:34:28 UTC-7, Don Y wrote:
....
Do folks \"do stupid things\" like replacing a fuse that blows with a larger
one thinking that will \"solve\" The Problem? Or, do they have a \"proper
respect\" for that which they don\'t understand?
Not commonly but I\'m sure they do.
[I am assuming a table lamp would have a much lighter gauge cord than
a large appliance (?) so oversizing the fuse could be a hazard]
The fuse is basically to protect the wiring, so yes it would be dangerous.
....

Stoves would be hard wired with their own circuit breaker.

While not a \"rule\", I think homes here tend to have outlets for almost
all devices, regardless of power consumption (circuit ampacity). This
makes it easy (low tech) to replace a stove/oven with a new one -- just
\"unplug\" the old and plug the new in its place.

E.g., none of our furnace, evap cooler, oven/stove, clothes dryer are
hard-wired. All have plugs/power cords. Though all have \"dedicated
circuits\" sized for their expected loads.
That is not common here in California. The only heavy duty device that has a user removable outlet in my home here is the clothes dryer.
....
 
T

Tabby

Guest
On Saturday, 29 August 2020 18:51:56 UTC+1, Don Y wrote:
On 8/28/2020 7:47 PM, Tabby wrote:

So where does the 13A come in? Is that the \"per appliance\" limit?

Mains plugs are 13A rated, 13A fused. They plug into usually 32A ring
circuits, less often 20A radials.

But not EVERY device is fused at 13A; 13A is the MAX that a plug can
be fused? I.e., you wouldn\'t fuse a table lamp at 13A... (we wouldn\'t fuse
a table lamp but would rely on the branch circuit\'s fusing to limit current
in a fault)

Assuming each device is fused at a size appropriate for the load it
represents, is there something that prevents a user from replacing the
fuse with one of higher rating?

All the plugs (and receptacles) are the same? So, there is nothing
that prevents a user from plugging into a \"too small ampacity\" circuit?
(i.e., all yours are 32A so that likely ensures circuit is larger
than any load).
All mains plugs are the same type except for shavers & toothbrushes.
Plugs take any of 2A 3A 5A 7A 10A 13A fuses, all of which are of identical dimensions & freely interchangeable. Most people only use 3A & 13A fuses.
When the system came out in the 40s people were encouraged to put the best fuse in according to appliance consumption. This was soon simplified to choosing 3A or 13A. Now all appliances are required to be safe with a 13A fuse & there is no expectation that users will have much clue what fuse to use. This means flexes can\'t be thinner than 0.5 square mm.

Of course there are still a few old appliances & lots of noncompliant Chinese stuff, some of which is not adequately fused with a 13A fuse. The good news on that point is that a 32A breaker is faster than a 13A fuse.

There is rarely any such thing as a socket circuit with inadequate ampacity.. Plugging more than 7.68kW continuous in is unrealistic. This is often exceeded in a kitchen but only for a minute or 2, which is not a problem. If some kid plugged 20kW of heaters the breaker would trip.


I.e., would you plug an electric stove into the mains with the same
plug/outlet? (our stove/oven is fused for 50A@240VAC)
Cookers & showers that exceed 13A have their own dedicated circuit. Electric showers go upto 10kW - gas & stored electric hot water delivers much more power. Not everyone likes a 10kW shower so stored HW is common in all-electric houses.

Cookers that switch power between different loads to stay under 13A are found at the cheap end of the scale. I remember using one decades ago. IIRC the oven was about 1.5kW and had power always available. The 1st ring was 1.5kW, ditto. The 2nd ring got power only when the oven stat switched the element off, so it worked but you weren\'t going to get anywhere near full power if you were using the oven. It only had 2 rings.


A typical US consumer will deal with maybe 5 or 6 different types
of receptacles (and, thus, plugs):
- unpolarized 2 prong (increasingly rare)
- polarized 2 prong (insulated devices not needing earth connection)
- 3 prong (120VAC+earth)
- 3 prong, 20A (neutral blade is orthogonal to hot blade: |-)
- 3 or 4 prong, 220V, 30A (clothes dryer)
- 3 or 4 prong, 220V, 50 or 60A (stove)
It is not possible, for example, to plug my clothes dryer into the outlet
for the oven -- even though the oven\'s branch circuit has a higher
ampacity. Likewise, my 12AWG extension cord bears a 20A plug (|-)
which makes it incompatible with most 15A receptacles (||).
Before today\'s 1947 square pin plug system the UK had the dreaded round pin system with 5 widely used types of plug & socket (plus more less common ones). Plugs were rated 2A, 5A, 15A. Some were 3 pin, some 2 pin. Sockets were few, unfused adaptors were in widespread use & often stacked. Users did not respect the current ratings. The result was little short of madness. Oh, and BC \'sockets\' had no particular current rating afaik. Yes it was common back then to plug things into the central light on the ceiling due to absence of sockets in many rooms!


Appliances with 2 mains leads are a rarity, but they do exist. Expect to
never see one though. Typically a tiny minority of hire tools.

That\'s a way around the ampacity limitation?
yes

E.g., here, two leads would
only be used for things that have \"backup\" power needs (e.g., servers).
If you needed more ampacity than a 15A (or 20A) circuit, you\'d run a
new branch circuit with the desired ampacity (typically also a 240V branch
circuit when loads get to be that big).
That\'s the normal approach anwyhere. But if you hire a tool for 2 or 3 days they don\'t expect you to rewire to accomodate it, so such rarities occasionally exist.


60A is as much as any non-huge house ever needs here.

What\'s \"non huge\"? Our home isn\'t what we\'d consider \"huge\" (3BR). I know
folks who live in places that you could get LOST in! :

100A is plenty for a large 5 bed. Not for a place with 20 beds though.

100A is \"comfortable\", here (as I said, we tend to be gluttons and don\'t
consider \"managing\" our loads).

You may have a whirlpool/jacuzzi bathtub (pump to circulate water),
a swimming pool, an outdoor spa/jacuzzi (circulation pump and heater!),
dual refrigerator, dedicated freezer, etc. So, a *200A* service isn\'t
necessarily a \"luxury\".

[larger homes often have several HVAC plants, pool, spa, etc.]

And, devices don\'t coordinate their power use so there\'s nothing to prevent
them from all TRYING to use whatever power they need (the consumer is
eventually conditioned against doing this by a circuit breaker repeatedly
tripping -- and his remedy is to add more capacity! :< )
Car charging points here are typically automatically switched off if/when the house draws lots of power elsewhere. Necessary on a 40-100A service. Nothing else gets this treatment. Greater demand management has been discussed but at this point it\'s not worth it.


Residences usually have few tariff options (ways that they can be billed)..
Here, our only real choice (neglecting impact of solar cogeneration on tariff)
is ToU (Time of Use) metering. But, given our high DAYTIME energy requirement
for cooling, it is a losing proposition for almost every homeowner.

Businesses tend to have different tariffs that can motivate them to more
actively manage their consumption. E.g., *peak* (demand) metering effectively
bills them for energy AS IF it was continuously being used at it\'s peak
measured rate. So, they have a big incentive to do load leveling and
time shifting.

For example, a hotel would typically network the individual HVAC units
placed in each guest room to stagger when they can each DEMAND power
(so, even though the device appears to come on when the guest tweaks the
temperature setting, it may not really be providing the heating/cooling
that is desired -- yet!). Occupancy sensors can shed loads when the
room is considered vacant.

Large businesses \"make ice\" at night in anticipation of the next day\'s
cooling load. They\'re effectively being billed for power they aren\'t
using, at night (shop is closed) so the recurring power cost is effectively
FREE! Instead, just pay for the non-recurring equipment costs!
We have a cheap overnight tariff, Economy 7, but it\'s not as good as it sounds. 7 hours of half price electricity overnight, but daytime cost is increased, so not worth having unless you have storage heaters, which are a crap option seldom seen now.


Air conditioning is the big killer in most places that I\'ve lived. As it\'s
inconvenient to (manually) \"switch off\" in order to shed load, you have to
assume its running almost always.

Yeah, we seldom have ac, and when we do we don\'t need a lot of power for
it.

Prior to whole-house AC, we\'d use individual units \"per room\". A typical
bedroom would be served by a 5000BTU unit which would draw ~3-5A (depending on
its efficiency rating). You\'d place one in EACH bedroom and they would
each operate independent of each other (so, you could see a 15A load, at
times). You\'d put something larger in a kitchen area because:
- it\'s often fighting an additional heat source
- the area is more open than a bedroom (which has a door that can be closed)
And, something else for other \"living areas\", etc.

There are still places, here, with K&T wiring. But, that is usually
supplemented by more modern additions to service. Too many \"things\"
eating too much *power*!

Many of our neighbors have 200A services (same size homes).

All our rubber 1950s wiring rotted away long ago. Must be different rubber
formulation, there\'s none left in service that I know of.

Asphalt.

I remember looking
at some in the 1980s, twisted pair in iron conduit as was very common then.
The insulation had all fallen off from the foot or so I could see, the wires
snaking round each other in mid air. Owner had no intention of rewiring..

Many older homes used it. And, typically had uninsulated wall spaces (through
which the wiring would travel). The lower capacity and lack of insulation
conspire to coerce BUYERS of such properties to rewire (original occupant
may have just left it be)

The last holdout I knew of was rewired a few years ago, way overdue. I
gather K&T is perfectly capable.

Yes, just don\'t dick with it! :> I still have rolls of asphalt-impregnated
tape lying around...
\'friction tape\'

We\'ve still got lots of prewar supply systems though, there was a huge
electrification drive in the 1930s.

By far, the more common \"legacy\" wiring is 2-wire \"BX\". The downside there
is the lack of reliable earth conductor at each Jbox/outlet.

The trend, here, is always towards \"more\" -- or <whatever>. E.g., new homes
now require 1\" copper water mains instead of the 3/4\" that was in use when
this home was built. Yet, water FIXTURES are sold with flow rate limiters!
shakes head
Same trend here, though we lag the US. Water incomers are normally 15mm, just over half inch. Regulations require much waste. Lighting could be on 1A cable these days, but regs still require 1 square mm (about 10A rated) cable.


NT
 
T

Tabby

Guest
On Sunday, 30 August 2020 04:34:28 UTC+1, Don Y wrote:
On 8/29/2020 6:59 PM, keith wright wrote:
On Saturday, 29 August 2020 10:51:56 UTC-7, Don Y wrote:
On 8/28/2020 7:47 PM, Tabby wrote:

So where does the 13A come in? Is that the \"per appliance\" limit?

Mains plugs are 13A rated, 13A fused. They plug into usually 32A ring
circuits, less often 20A radials.

But not EVERY device is fused at 13A; 13A is the MAX that a plug can be
fused? I.e., you wouldn\'t fuse a table lamp at 13A... (we wouldn\'t fuse
a table lamp but would rely on the branch circuit\'s fusing to limit
current in a fault)

There are 2 or 3 standard fuses used depending upon the device. 2A, 5A and
13A or similar.

Do folks \"do stupid things\" like replacing a fuse that blows with a larger
one thinking that will \"solve\" The Problem? Or, do they have a \"proper
respect\" for that which they don\'t understand?
Was once common. As was foil or slivers of wire to replace fuses, plugs held together with tape etc. All that\'s long gone now.


[I am assuming a table lamp would have a much lighter gauge cord than
a large appliance (?) so oversizing the fuse could be a hazard]
no

All the plugs (and receptacles) are the same? So, there is nothing that
prevents a user from plugging into a \"too small ampacity\" circuit? (i.e.,
all yours are 32A so that likely ensures circuit is larger than any
load).

I.e., would you plug an electric stove into the mains with the same
plug/outlet? (our stove/oven is fused for 50A@240VAC)

Stoves would be hard wired with their own circuit breaker.

While not a \"rule\", I think homes here tend to have outlets for almost
all devices, regardless of power consumption (circuit ampacity). This
makes it easy (low tech) to replace a stove/oven with a new one -- just
\"unplug\" the old and plug the new in its place.
Sensible, but not done here for cookers, showers & other >13A loads. Electricians would rather pocket the cost of a plug & socket & be able to charge the customer again later. And afaik there are no >13A plugs & sockets that are approved for domestic use, so it wouldn\'t be legal anyway.


NT
 
D

Don Y

Guest
On 8/29/2020 11:42 PM, Tabby wrote:
On Saturday, 29 August 2020 18:51:56 UTC+1, Don Y wrote:
On 8/28/2020 7:47 PM, Tabby wrote:

All the plugs (and receptacles) are the same? So, there is nothing that
prevents a user from plugging into a \"too small ampacity\" circuit? (i.e.,
all yours are 32A so that likely ensures circuit is larger than any
load).

All mains plugs are the same type except for shavers & toothbrushes. Plugs
take any of 2A 3A 5A 7A 10A 13A fuses, all of which are of identical
dimensions & freely interchangeable. Most people only use 3A & 13A fuses.
When the system came out in the 40s people were encouraged to put the best
fuse in according to appliance consumption. This was soon simplified to
choosing 3A or 13A. Now all appliances are required to be safe with a 13A
fuse & there is no expectation that users will have much clue what fuse to
use. This means flexes can\'t be thinner than 0.5 square mm.
?? That\'s like our 20AWG wire size. We\'d typically wire a 15A branch
circuit with 14AWG (2 sq mm). An appliance cord (\"flex\"?) would typically
be ~16AWG for that sort of ampacity. (e.g., a clothes iron would use 18AWG
for a ~9A load). Countertop appliances (kitchen) tend to be sold with VERY
short cords -- often ~18\" (outlets are required to be < 4 ft apart so a 2 ft
cord *should* be sufficient).

There is rarely any such thing as a socket circuit with inadequate ampacity.
Plugging more than 7.68kW continuous in is unrealistic. This is often
exceeded in a kitchen but only for a minute or 2, which is not a problem. If
some kid plugged 20kW of heaters the breaker would trip.
Again, my clothes dryer is on a 30A 240VAC branch circuit; and the
stove/oven is on a 50A 240VAC circuit. Both have \"power cords\" into
\"receptacles/sockets\". The \"plugs\" are considerably meatier than
a normal appliance cord and unlikely to be unmated often.

I.e., would you plug an electric stove into the mains with the same
plug/outlet? (our stove/oven is fused for 50A@240VAC)

Cookers & showers that exceed 13A have their own dedicated circuit. Electric
showers go upto 10kW - gas & stored electric hot water delivers much more
power. Not everyone likes a 10kW shower so stored HW is common in
all-electric houses.
Water heaters tend to have storage, here. \"Demand\" water heaters tend to
be rarer and harder to effectively size for two concurrent uses. It\'s not
often that you have a hefty \"service\" available in the location of your
water heater (even electric TANKED water heaters operate at relatively low
power levels). And, you often have (relatively) long periods of time
between \"big\" hot water uses -- to give the heater a chance to recharge
the 40 - 80 gallons of water that it holds heated.

[In the desert southwest, 2 baths + kitchen would tend to need a 25KW tankless
whereas a tanked heater would use ~5KW -- for really luxuriant showers! :> ]

Cookers that switch power between different loads to stay under 13A are
found at the cheap end of the scale. I remember using one decades ago. IIRC
Ah -- so the load management is done within that single appliance? I\'m not
sure how hard it would be to cook under those constraints. E.g., we often
have all four stovetop burners in use when prepping a meal -- though the
oven only sees real use when baking (and it\'s too hard to manage cooking
and baking at the same time!)

the oven was about 1.5kW and had power always available. The 1st ring was
1.5kW, ditto. The 2nd ring got power only when the oven stat switched the
element off, so it worked but you weren\'t going to get anywhere near full
power if you were using the oven. It only had 2 rings.
\"Rings\" are \"stovetop burners\"?
A typical US consumer will deal with maybe 5 or 6 different types of
receptacles (and, thus, plugs)

Before today\'s 1947 square pin plug system the UK had the dreaded round pin
system with 5 widely used types of plug & socket (plus more less common
ones). Plugs were rated 2A, 5A, 15A. Some were 3 pin, some 2 pin. Sockets
were few, unfused adaptors were in widespread use & often stacked. Users did
not respect the current ratings. The result was little short of madness. Oh,
and BC \'sockets\' had no particular current rating afaik. Yes it was common
back then to plug things into the central light on the ceiling due to
absence of sockets in many rooms!
Yes, we would ship products to europe (in general) without a power cord
figuring the end user would sort out what he needed.

For the US market, you\'re almost always dealing with a 2 prong or three prong
15A plug -- both will fit the same 15 or 20A receptacle.

E.g., here, two leads would only be used for things that have \"backup\"
power needs (e.g., servers). If you needed more ampacity than a 15A (or
20A) circuit, you\'d run a new branch circuit with the desired ampacity
(typically also a 240V branch circuit when loads get to be that big).

That\'s the normal approach anwyhere. But if you hire a tool for 2 or 3 days
they don\'t expect you to rewire to accomodate it, so such rarities
occasionally exist.
The largest electric tools commonly used would safely run on a 20A circuit
(available indoor or outdoor).

And, devices don\'t coordinate their power use so there\'s nothing to
prevent them from all TRYING to use whatever power they need (the consumer
is eventually conditioned against doing this by a circuit breaker
repeatedly tripping -- and his remedy is to add more capacity! :< )

Car charging points here are typically automatically switched off if/when
the house draws lots of power elsewhere. Necessary on a 40-100A service.
Nothing else gets this treatment. Greater demand management has been
discussed but at this point it\'s not worth it.
I can\'t speak to that as we don\'t drive an electric vehicle. Several
neighbors do and I wasn\'t under the impression that they had special
power needs (\"plug-in hybrids\"?).

Large businesses \"make ice\" at night in anticipation of the next day\'s
cooling load. They\'re effectively being billed for power they aren\'t
using, at night (shop is closed) so the recurring power cost is
effectively FREE! Instead, just pay for the non-recurring equipment
costs!

We have a cheap overnight tariff, Economy 7, but it\'s not as good as it
sounds. 7 hours of half price electricity overnight, but daytime cost is
increased, so not worth having unless you have storage heaters, which are a
crap option seldom seen now.
Exactly. Here, our big loads are refrigeration (cooling) and storing \"cool\"
is expensive. A typical home solar installation really only worries about
trying to cover the cooling costs of the house as that\'s the costly part
(and hard to timeshift -- but, greatest when the sun happens to be out! :> )
 
D

Don Y

Guest
On 8/29/2020 8:47 PM, keith wright wrote:
Stoves would be hard wired with their own circuit breaker.

While not a \"rule\", I think homes here tend to have outlets for almost all
devices, regardless of power consumption (circuit ampacity). This makes
it easy (low tech) to replace a stove/oven with a new one -- just \"unplug\"
the old and plug the new in its place.

E.g., none of our furnace, evap cooler, oven/stove, clothes dryer are
hard-wired. All have plugs/power cords. Though all have \"dedicated
circuits\" sized for their expected loads.

That is not common here in California. The only heavy duty device that has a
user removable outlet in my home here is the clothes dryer. ...
Local codes always have precedence. E.g., in Chitown, everything was run
in EMT.

I think \"drop in\" appliances (cooktops, wall-mounted ovens, etc.) tend to
have hard-wired connections -- because they are inherently seen as more
permanent.

\"Slide in\" appliances (dryer, free-standing stove/oven, etc.) have plugs
as they can be more readily \"slid back out\". E.g., I\'d wager your
refrigerator and washing machine have plugs (but smaller load -- but
comparable to garbage disposal!) though no different than the oven in
terms of PHYSICAL ease of replacement.

Is your garbage disposal hard-wired? Dishwasher? Furnace? Even our evap
cooler is fitted with plugs (one for the 240V blower and another for the
120V pumps and controls).

With the exception of disposal, all of these have dedicated outlets.
 
T

Tabby

Guest
On Sunday, 30 August 2020 15:19:06 UTC+1, Don Y wrote:
On 8/29/2020 11:42 PM, Tabby wrote:
On Saturday, 29 August 2020 18:51:56 UTC+1, Don Y wrote:
On 8/28/2020 7:47 PM, Tabby wrote:

All the plugs (and receptacles) are the same? So, there is nothing that
prevents a user from plugging into a \"too small ampacity\" circuit? (i.e.,
all yours are 32A so that likely ensures circuit is larger than any
load).

All mains plugs are the same type except for shavers & toothbrushes. Plugs
take any of 2A 3A 5A 7A 10A 13A fuses, all of which are of identical
dimensions & freely interchangeable. Most people only use 3A & 13A fuses.
When the system came out in the 40s people were encouraged to put the best
fuse in according to appliance consumption. This was soon simplified to
choosing 3A or 13A. Now all appliances are required to be safe with a 13A
fuse & there is no expectation that users will have much clue what fuse to
use. This means flexes can\'t be thinner than 0.5 square mm.

?? That\'s like our 20AWG wire size. We\'d typically wire a 15A branch
circuit with 14AWG (2 sq mm). An appliance cord (\"flex\"?) would typically
be ~16AWG for that sort of ampacity. (e.g., a clothes iron would use 18AWG
for a ~9A load). Countertop appliances (kitchen) tend to be sold with VERY
short cords -- often ~18\" (outlets are required to be < 4 ft apart so a 2 ft
cord *should* be sufficient).
0.5mm^2 is only for low current stuff. 13A requires 1.5.


There is rarely any such thing as a socket circuit with inadequate ampacity.
Plugging more than 7.68kW continuous in is unrealistic. This is often
exceeded in a kitchen but only for a minute or 2, which is not a problem. If
some kid plugged 20kW of heaters the breaker would trip.

Again, my clothes dryer is on a 30A 240VAC branch circuit; and the
stove/oven is on a 50A 240VAC circuit. Both have \"power cords\" into
\"receptacles/sockets\". The \"plugs\" are considerably meatier than
a normal appliance cord and unlikely to be unmated often.

I.e., would you plug an electric stove into the mains with the same
plug/outlet? (our stove/oven is fused for 50A@240VAC)

Cookers & showers that exceed 13A have their own dedicated circuit. Electric
showers go upto 10kW - gas & stored electric hot water delivers much more
power. Not everyone likes a 10kW shower so stored HW is common in
all-electric houses.

Water heaters tend to have storage, here. \"Demand\" water heaters tend to
be rarer and harder to effectively size for two concurrent uses. It\'s not
often that you have a hefty \"service\" available in the location of your
water heater (even electric TANKED water heaters operate at relatively low
power levels). And, you often have (relatively) long periods of time
between \"big\" hot water uses -- to give the heater a chance to recharge
the 40 - 80 gallons of water that it holds heated.

[In the desert southwest, 2 baths + kitchen would tend to need a 25KW tankless
whereas a tanked heater would use ~5KW -- for really luxuriant showers! :> ]

Cookers that switch power between different loads to stay under 13A are
found at the cheap end of the scale. I remember using one decades ago. IIRC

Ah -- so the load management is done within that single appliance? I\'m not
yup


sure how hard it would be to cook under those constraints. E.g., we often
have all four stovetop burners in use when prepping a meal -- though the
oven only sees real use when baking (and it\'s too hard to manage cooking
and baking at the same time!)
Most folk never use more than 2 rings anyway. They\'re not for everyone. \'Baby belling\' is the best known of these. An early variant:
https://foodheroesandheroines.wordpress.com/2012/04/06/2-charles-reginald-belling1884-1965/
You can also get 13A limited 4 ring hobs, it saves calling an electrician


the oven was about 1.5kW and had power always available. The 1st ring was
1.5kW, ditto. The 2nd ring got power only when the oven stat switched the
element off, so it worked but you weren\'t going to get anywhere near full
power if you were using the oven. It only had 2 rings.

\"Rings\" are \"stovetop burners\"?
yup

NT

A typical US consumer will deal with maybe 5 or 6 different types of
receptacles (and, thus, plugs)

Before today\'s 1947 square pin plug system the UK had the dreaded round pin
system with 5 widely used types of plug & socket (plus more less common
ones). Plugs were rated 2A, 5A, 15A. Some were 3 pin, some 2 pin. Sockets
were few, unfused adaptors were in widespread use & often stacked. Users did
not respect the current ratings. The result was little short of madness. Oh,
and BC \'sockets\' had no particular current rating afaik. Yes it was common
back then to plug things into the central light on the ceiling due to
absence of sockets in many rooms!

Yes, we would ship products to europe (in general) without a power cord
figuring the end user would sort out what he needed.

For the US market, you\'re almost always dealing with a 2 prong or three prong
15A plug -- both will fit the same 15 or 20A receptacle.

E.g., here, two leads would only be used for things that have \"backup\"
power needs (e.g., servers). If you needed more ampacity than a 15A (or
20A) circuit, you\'d run a new branch circuit with the desired ampacity
(typically also a 240V branch circuit when loads get to be that big).

That\'s the normal approach anwyhere. But if you hire a tool for 2 or 3 days
they don\'t expect you to rewire to accomodate it, so such rarities
occasionally exist.

The largest electric tools commonly used would safely run on a 20A circuit
(available indoor or outdoor).

And, devices don\'t coordinate their power use so there\'s nothing to
prevent them from all TRYING to use whatever power they need (the consumer
is eventually conditioned against doing this by a circuit breaker
repeatedly tripping -- and his remedy is to add more capacity! :< )

Car charging points here are typically automatically switched off if/when
the house draws lots of power elsewhere. Necessary on a 40-100A service.
Nothing else gets this treatment. Greater demand management has been
discussed but at this point it\'s not worth it.

I can\'t speak to that as we don\'t drive an electric vehicle. Several
neighbors do and I wasn\'t under the impression that they had special
power needs (\"plug-in hybrids\"?).

Large businesses \"make ice\" at night in anticipation of the next day\'s
cooling load. They\'re effectively being billed for power they aren\'t
using, at night (shop is closed) so the recurring power cost is
effectively FREE! Instead, just pay for the non-recurring equipment
costs!

We have a cheap overnight tariff, Economy 7, but it\'s not as good as it
sounds. 7 hours of half price electricity overnight, but daytime cost is
increased, so not worth having unless you have storage heaters, which are a
crap option seldom seen now.

Exactly. Here, our big loads are refrigeration (cooling) and storing \"cool\"
is expensive. A typical home solar installation really only worries about
trying to cover the cooling costs of the house as that\'s the costly part
(and hard to timeshift -- but, greatest when the sun happens to be out! :> )
 
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