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Analog panel meter questions thread

DashApple

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Thought it was : P .

We only get single phase 230V in are homes .... Though 40A @ 230V can be fun .
 



diachi

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Thought it was : P .

We only get single phase 230V in are homes .... Though 40A @ 230V can be fun .

Yeah, I remember, I miss being able to pull >3kW out of a single standard outlet without tripping a breaker. :(
 

Cyparagon

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In Canada the mains power that comes into a house is 3 phase 240VAC.
I know it's common in Europe to have residential 3phase, but after some googling, I'm reasonably certain you're wrong. All the canadian load centers that pop up on a search have just the two main circuits - split phase.
 

Benm

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There is no way to get 110V outlets running from a 230/400 three phase system unless you use a stepdown transformer.

In the past some systems here used 127 volts between phase and neutral, resulting in 220 volts between phases (triphase, not antiphase!).

I know the spit-phase (antiphase) system in fairly common in the US, such that you get both 120 and 240 volt outlets, but didn't know canada used this too. I also have no idea what purpose this serves - triphase is obviously useful for powering things like electrical motors, but antiphase... just for voltage compatibility or power availability from a single outlet?
 

Seoul_lasers

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In Canada the mains power that comes into a house
is 3 phase 240VAC. All the standard wall receptacles
are wired 1 phase 120VAC.
The Stoves and Clothes Dryers are plugged into 240VAC
3 phase wall receptacles...

For quick low power 240VAC testing in the shop I use a
120VAC to 240VAC step up transformer.

But I know what you mean....:beer:

Jerry

The only 3phase in Canada is for industrial buildings, at least here in BC. We have 120Vac (single Phase) and 240Vac "dual phase" what is technically called a split phase (2x120V) as others here are mentioning.

My next door neighbour has 3 phase for compressors, welders and a metal lathe. He's on 120/208Vac.. It's rated for 200A. He's only permitted to use 3 phase in his workshop, his house runs 120V/240V residential single and split phases.
This kind of service for residential is EXTREMELY expensive.
 
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Cyparagon

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but antiphase... just for voltage compatibility or power availability from a single outlet?
It's a safety thing, as far as I know. Just as a 15kV neon sign transformer is center-tapped so the highest voltage to ground is 7.5kV, we center tap mains to allow 240V for some (high power) appliances, but have a maximum of 120V to ground.
 

lasersbee

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The only 3phase in Canada is for industrial buildings, at least here in BC. We have 120Vac (single Phase) and 240Vac "dual phase" what is technically called a split phase (2x120V) as others here are mentioning.

My next door neighbour has 3 phase for compressors, welders and a metal lathe. He's on 120/208Vac.. It's rated for 200A. He's only permitted to use 3 phase in his workshop, his house runs 120V/240V residential single and split phases.
This kind of service for residential is EXTREMELY expensive.
Ahhh. You caught me... I should have said Split Single Phase...:yabbem:

You are absolutely correct. It is 3 wire Split single phase.
Two hot wites at 240VAC between them and a neutral
wire to each hot wire at 120VAC each plus a dedicated
ground/earth wire.

Jerry
 
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Benm

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I sort of get the safety thing, you 'only' get 120 volts between live and neutral/ground, which would be less dangerous that the 230 volts we get over here, though still be considered very dangerous.

The 180 degree 'split phase' thing is virtually unheard of in europe. Getting 3 phase supply to a house is not that uncommon - it is often used to drive motors in ventillation systems, as well as for elevators and things like that. You won't find 3 phase outlets on the wall in the average home, but you can have them installed if you need to for things like machines or electrical stoves.

What i don't really get is how you power domestic applicances from 120 volts. I have my coffe maker (say 500 watts), microwave oven (about 1 kW) and washing machine (about 2 kW when heating) powered from one group. With 230V/16A available that is not much of a probem, but at half the voltage it'd take whopping 30 amps.

Also european power plugs (the schuko type) and especially british plugs are -very- beefy compared to what you see on many american leads. We do have pretty flimsy (but still far bigger compared to US plugs) flat ungrounded euro-plugs for very light loads (like a table lamp or phone charger), but even things like laptop adapters use the bigass schuko plugs (mainly for grounding i suppose).
 

Cyparagon

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What i don't really get is how you power domestic applicances from 120 volts. I have [several things] powered from one group.
Simple. Install more circuits (or "groups"). Large appliances often have their own circuit feed and respective breakers, and the largest (anything over 2kW or so) have 240V input.

We've got more copper, more breakers, and more available power than in a European house. 240V 200A (sometimes 100A in smaller or older houses) is standard residential mains feed, here.



Ahhh. You caught me... I should have said 2 Phase...:yabbem:
No. Still one phase.

"Since the two phasors do not define a unique direction of rotation for a revolving magnetic field, a split single-phase is not a two-phase system."
 
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DashApple

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We have a 80A main fuse, though in newer homes its usually 100A .
 
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Benm

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Simple. Install more circuits (or "groups"). Large appliances often have their own circuit feed and respective breakers, and the largest (anything over 2kW or so) have 240V input.

We've got more copper, more breakers, and more available power than in a European house. 240V 200A (sometimes 100A in smaller or older houses) is standard residential mains feed, here.

Wow, that is a lot of wiring indeed.

In europe you'd get something like 3 230V/16A groups in small apartment to 6 230V/16A ones in a full house, though 25 or 40A are also available if required (standard wall socket is rated to 16A continous, though they survive double that easily).

I have a slighly larger appartment that has 5 groups of 230V/16A each routed to various sockets, lights and all.

The 16A thing is mostly due to internal wiring, as i recall 2.5 mm2 wired have to be fused at 16A, while 3.5 or 4 mm2 wires can be fused at 25A. The upstream breaker from the power meter usually is 40A regardless, and of the slow-triggering type.
 

DashApple

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Uk is usually three rings for sockets , one up , one down , one kitchen all fused by 32A breakers run in a ring of 2.5mm2 . Two lighting circuits fused at 6A / 10A and then maybe a cooker or shower circuit .

That's the normal setup for new homes
 
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Seoul_lasers

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Ahhh. You caught me... I should have said Split Single Phase...:yabbem:

You are absolutely correct. It is 3 wire Split single phase.
Two hot wites at 240VAC between them and a neutral
wire to each hot wire at 120VAC each plus a dedicated
ground/earth wire.

Jerry
Actually I hear a lot from electrical workers calling the 240Vac, dual phase which is not true... Loose terminology as both the 120Vac feeds are in phase of each other. The split single phase is the appropriate term.
 

Benm

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You can call it whatever you like.

There are 2 systems in use:

- 3 phases 120 degrees from eachother, with an optional neutral

- 2 phases 180 degrees from eachother, also with an optional neutral

The first system is common in europe with 400 volts between phases and 230 volts between any phase and neutral. Most domestic appliances are fitted between one of the phases and neutral, but some things like motors use all phases on a specific socket.

The second system has 110 or 120 volts on each phase respective to neutral, and double that voltage between phases. This has no use for powering things like motors since the order you connect the phases in does not dictate rotational direction as it does in 3 phase systems.
 




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