Why are motors not current limited?

[Jimmy Wilkinson Knife]

I just tested a vacuum cleaner rated at 2kW. It consumed 1.95kW of electricity.

[Jimmy Wilkinson Knife]

And Italy apparently manages with 3kW for their entire house. But then some of us are a little bit more advanced.

[trader_4]

+1

I see nothing wrong, IDK what K is talking about.

[Clare Snyder]

Today's AC uses about half what my old 45 year old unit used. The circulating fan in the air handler is also about 50% more efficient.

[Clare Snyder]

In that application both the outlets MUST be on the same breaker/circuit.

Code does not allow, from memory, 2 circuits on the same device unless the breakers are "tied" -- cannot have one circuit live and the other off.

[Jimmy Wilkinson Knife]

Your outlets don't do 2.2kW.

[Clare Snyder]

SNIPPPP

So for the same power, 240 uses LIGHTER wire. (higher voltage= lower current for same power)

For the same power, we would have 7.5 amp circuits - - - -

Code does NOT allow them to be fed from separate circuits unless the breaker is "tied" - in other words either an edison circuit, or a "virtual edison" circuit with the neutrals paired at the breaker

Had switched outlets (the big nasty old British style) in my house in Zambia.

MISERABLE things!!!!!

Aparently the thinking is with higher voltage you get arcing when disconnecting the load - but nothing prevents pulling the plug or plugging it in with the switch on - so that's kinda lame.

Also kinda stupid to use blades about 8 times as heavy as the blades on a 15 amp 120 volt plug - the darn things are MASSIVE.

Same thing in Burkina Faso - but there you get to "pick your poison" as there does not appear to be any "standard" - some places use French style euro plugs, some use South African, some use british, and some use American - and it can be 240 or 120 volts, 50 or 60 hz because there is a lot of local private power generation.

ANd very often 3 way switches - or even 4 way - one at rach entrance to a room. My dad used to put 4-ways in master bedrooms - one at the door and one at each side of the bed - - -

Really handy to be able to run the toaster and the coffeemaker or kettle side by side without running cords across the contertop - and without tripping the breaker or blowing the fuse - - -

[Clare Snyder]

So what - the fuse is to protect the WIRING - NOT the device. The device generally carries it's own protection if required.

Unlike inbred scotsmen, most of us know enough to release the switch if we overload a hand tool like a saw or grinder to prevent letting the magic smoke out.

Double Insulated devices use 2 pin polarized non grounded cords. Other devices use 3 wire grounded cords.

2 wire plugs fit 3 wire outlets. 2 wire outlets are basically history - only used in very specific applications - usually on devices - - or things like "isolated" shaver outlets in bathrooms - no longer allowed for regular residential wiring.

I call that "simplification" - nor "complication"

[Jimmy Wilkinson Knife]

ote:

...

So not a left wing f***ed up government controlled mess with no personal= freedom like the UK.

-- =

What has four legs, is big, green, fuzzy, and if it fell out of a tree w= ould kill you? A pool table.

[Jimmy Wilkinson Knife]

nywhere in the house. Power tools, fan heaters, kettles, irons, two thi= ngs on one adapter, there are so many things that half the power just ai= n't enough for. It's so much more convenient in the UK to be able to po= wer anything in any room from any socket.

t hot water to make coffee, tea, or to put in a saucepan to cook food?

uld you plug that in in your home?

The exact model I was going to buy, but at only =A355.

Then I found a Hyundai (more reliable well known make) at =A345.

These things go through concrete blocks or brick like it was butter.

-- =

We always hold hands. If I let go, she shops.

[trader_4]

ywhere in the house. Power tools, fan heaters, kettles, irons, two things on one adapter, there are so many things that half the power just ain't eno ugh for. It's so much more convenient in the UK to be able to power anythi ng in any room from any socket.

hot water to make coffee, tea, or to put in a saucepan to cook food?

ld you plug that in in your home?

And here is the 110V version that I could plug in here:

Anything else I can help you with? Again, this is a specmanship issue. I suspect you're 2200 watt rating is with a locked rotor or similar. We have angle grinders, including 9" ones, out the whazoo that plug into a 15A receptacle. There is no "problem".

[gfretwell]

True and now multiwire circuits also require that the conductors be "grouped" in the panel. (generally that means zip tied in a bundle)

[Clare Snyder]

Not an issue when using non metallic sheathed cable (aka ROMEX) or metallic cable (AKA BX) - it's really only an issue when running individual wires in conduit - not noemally done in single family residential units outside of perhaps NYC and ChiTown.

[Jimmy Wilkinson Knife]

Does it hell. I find myself tapping my foot for a kettle or microwave. Fuck knows how people managed to cook in ovens. If you're hungry now, you'll be starving in an hour.

I think if you put 120V across a 240V heating element it wouldn't toast at all. P=V^2/R, so one quarter of the heat. You'd just get warm bread.

[Jimmy Wilkinson Knife]

800W?! That must take hours.

[gfretwell]

It may shock you that they actually build things other that 1&2 family homes ;-)

[gfretwell]

OK that is about a pound of water (a pint or .5 l according to the directions) Call it 145 BTU assuming you start with 67 F water.

800w/hr = 2730 BTU so it is about 1/19th of an hour, ~3.15 minutes.

I think you can wait 3 minutes for Ramen. (that is about as long as it takes in my microwave too)

[krw]

That's what I said, "usage of central AC has increased".

[Clare Snyder]

No shock at all - and even a lot od MURBs are built wired with cable instead of conduit - - - -

[Clare Snyder]

Most microwaves are 800 to 1000 watts, so that makes sense.

Not too long ago electric tea kettles were very common in Canada and almost unheard of in most of the USA. I remember friends coming to visit fromthe states back in the sixties buying several and taking them home as gifts forfamily and friends. They had never seen them!!!