Mains

[Ross Craney]

I'm talking in the context of the opening post. So disregarding starting currents , power factors , mechanical load variations etc we are talking about a cooling / refridgeration compressor that is running & then reducing the supplied voltage from 220V to 200V. Short of stalling the motor the only thing that will happen is it will run slower & less efficiently. I stand ready to be corrected.

 

[Mr RB]

It's common for AC motors to be destroyed by sustained brownouts. Generally fridges. I'm guessing since a fridge motor drives a piston conpressor (high peak load once per rev) it would stall and the sustained stall is probably the killer. AND maybe there is a chance the compressor will fail to re-start when full power is resumed, that would be really nasty...

 

[Bob Scott]

Not an option, or a problem, in the UK - household sockets are wired to ring mains (usually one ring per floor). So each 13A socket is fed via two pieces of 2.5mm twin and earth cable, giving 5mm capacity. Each mains plug is also individually fused, with a maximum 13A fuse, other common values 10A, 5A, 3A.

By 2.5mm, you mean 2.5 square mm, right? I looked it up on Wikipedia. That is very close to our AWG 14 - what we use for 15 amp circuits. That would be ~SWG 16. Do you use SWG wire guage or are you metric now? Is your electrical code merging with the European sytem? I know ours and the US code are just about completely merged.

We should start a new thread on world electrical standards.

Anything higher than that, such as cookers, showers etc. are wired individually direct from the fusebox, using 6mm or greater cabling.

Wikipedia did not mention a UK residence fusebox except for the main breaker. Here is my reference:
Electrical wiring in the United Kingdom - Wikipedia, the free encyclopedia
Does this mean you also have a breaker panel with breakers for your individual ring circuits and individual heavy appliances, plus fuses in the ring outlet boxes plus fuses in the toaster or table lamp plugs now? (I was going to say "radio" but they all use wall warts now.)

If I understand correctly, a "downlighter" is a branch from a ring outlet box that is used to power a ceiling lighting fixture, including a wall switch. Is this correct?

Bob

 

[Ross Craney]

I'm talking in the context of the opening post. So disregarding starting currents , power factors , mechanical load variations etc we are talking about a cooling / refridgeration compressor that is running & then reducing the supplied voltage from 220V to 200V. Short of stalling the motor the only thing that will happen is it will run slower & less efficiently. I stand ready to be corrected.

I get a feeling that I just proved myself wrong. If it runs slower then the relative load has increased & hence will draw more current.
Ok I surrender !

 

[crutschow]

I'm talking in the context of the opening post. So disregarding starting currents , power factors , mechanical load variations etc we are talking about a cooling / refridgeration compressor that is running & then reducing the supplied voltage from 220V to 200V. Short of stalling the motor the only thing that will happen is it will run slower & less efficiently. I stand ready to be corrected.

So was I.

The motor runs less efficiently due to the increase in motor current and consequent higher IR loss which heats up the motor.

 

[Nigel Goodwin]

By 2.5mm, you mean 2.5 square mm, right? I looked it up on Wikipedia. That is very close to our AWG 14 - what we use for 15 amp circuits. That would be ~SWG 16. Do you use SWG wire guage or are you metric now?

Mains wiring has been metric pretty well all the time I've been involved in electronics.

Is your electrical code merging with the European sytem? I know ours and the US code are just about completely merged.

No, the UK is completely separate, we wouldn't want to downgrade to a lower standard.

Does this mean you also have a breaker panel with breakers for your individual ring circuits and individual heavy appliances, plus fuses in the ring outlet boxes plus fuses in the toaster or table lamp plugs now? (I was going to say "radio" but they all use wall warts now.)

Each ring main will have it's own fuse in the fusebox, plus each lighting circuit will have it's own fuse as well (like ring mains, usually aseparate circuit for each floor). Then individual heavy appliances (all of which are wired in, not plugged) will have their own direct feeds from the fusebox.

In my house I ran a piece of 6mm cable from the fusebox to the attic, and fitted a separate fusebox on it, powering a single ring main, and a single lighting circuit.

Sockets don't have fuses (apart from the ring main one), but the plug on the end of each appliance does, sized according to the appliance. Maximum size is 13A, giving just over 3000W capability.

If I understand correctly, a "downlighter" is a branch from a ring outlet box that is used to power a ceiling lighting fixture, including a wall switch. Is this correct?

As far as I'm aware a 'downlighter' is just a small light fitting, concealed in the ceiling, and shining directly 'down'. Lights are fed from their own circuits, not from the ring main - and use 1mm cable (or 1.5mm), instead of 2.5mm.

 

[Mikebits]

No, the UK is completely separate, we wouldn't want to downgrade to a lower standard.

Now that is just impolite.

 

[Nigel Goodwin]

Now that is just impolite.

But perfectly true!

 

[Mikebits]

But perfectly true!

Perhaps it is true, but your condescending tone is inappropriate for a moderator.

And everyone calls us Yanks arrogant.

 

[Nigel Goodwin]

Perhaps it is true, but your condescending tone is inappropriate for a moderator.

Nothing condescending at all?, just a plain statement of fact.

If I was been condescending I would have added a smiley.

 

[grim]

none of the European connections are as good as the UK 13A plug and socket.

also UK safety standards are enforced a lot better than some other local countries. I bet we've all seem some dodgy wiring in hotels..

 

[Nigel Goodwin]

none of the European connections are as good as the UK 13A plug and socket.

also UK safety standards are enforced a lot better than some other local countries. I bet we've all seem some dodgy wiring in hotels..

My boss has a modern built villa out in Spain, but you can't even take a UK vacuum cleaner out there, as the entire supply to the villa is too small to power it!.

 

[Mikebits]

Nothing condescending at all?, just a plain statement of fact.

If I was been condescending I would have added a smiley.

You speak matter of factually, but what facts do you go by. I have been to Europe and UK for that matter, I have seen nothing worth bragging about as far as infrastructure is concerned, when was the last time you have been to the US? I think you allow your preconceived notions and negative thoughts about Americans to dissuade you from keeping a fair and open mind.

 

[Nigel Goodwin]

You speak matter of factually, but what facts do you go by. I have been to Europe and UK for that matter, I have seen nothing worth bragging about as far as infrastructure is concerned, when was the last time you have been to the US? I think you allow your preconceived notions and negative thoughts about Americans to dissuade you from keeping a fair and open mind.

Who mentioned America? - I've never been there - but from what you see on programmes like 'This Old House' (love that programme) such electrical wiring practices wouldn't be allowed here. Perhaps it's the difference in voltage?, with 110V requiring less regulations.

But a country who has a system that allows massive 'brown-outs' affecting millions has some serious electricty supply issues. I'm aware that it's just so much bigger, but why (how?) can cascading failures happen?.

 

[Mikebits]

Who mentioned America? - I've never been there - but from what you see on programmes like 'This Old House' (love that programme) such electrical wiring practices wouldn't be allowed here. Perhaps it's the difference in voltage?, with 110V requiring less regulations.

But a country who has a system that allows massive 'brown-outs' affecting millions has some serious electricty supply issues. I'm aware that it's just so much bigger, but why (how?) can cascading failures happen?.

I guess you did not mention America in particular, but your response was to a North American, so innuendo still applies.

We do have brown outs from time to time, mostly because power demand exceeds supply. Considering we have 300 million people in the US, compared to 60 million in UK, one might expect power requirements to differ. To be honest, I have only experienced maybe one or two brownouts in a great many years. Do not let media influence your thinking, if I did the same, I would think Gordon Ramsey was the leader of UK

 

[Nigel Goodwin]

I guess you did not mention America in particular, but your response was to a North American, so innuendo still applies.

I don't see where?

Is your electrical code merging with the European sytem?

No, the UK is completely separate, we wouldn't want to downgrade to a lower standard.

We do have brown outs from time to time, mostly because power demand exceeds supply. Considering we have 300 million people in the US, compared to 60 million in UK, one might expect power requirements to differ. To be honest, I have only experienced maybe one or two brownouts in a great many years.

I can't say I realised the difference was only five times, but regardless of numbers, cascading failures shouldn't occur.

Perhaps they don't any more? - when was the last one?.

Do not let media influence your thinking, if I did the same, I would think Gordon Ramsey was the leader of UK

He would do a better job than the other Gordon!

 

[Mikebits]

I love Mr. Ramsey, Brilliant man. Have seen all the F-word shows, and Hells Kitchen shows.

 

[Nigel Goodwin]

I love Mr. Ramsey, Brilliant man. Have seen all the F-word shows, and Hells Kitchen shows.

Never watched the F-word shows, but Hells Kitchen was really good - where do they find all the idiots trying to run businesses?, on both sides of the pond.

 

[Mikebits]

I watch the F-word on our BBC channel. It seems Hells kitchen candidates are destined to doom as 60% fail after Gordon visits them. I think they just don't listen very good.

 

[Nigel Goodwin]

I watch the F-word on our BBC channel. It seems Hells kitchen candidates are destined to doom as 60% fail after Gordon visits them. I think they just don't listen very good.

Yes, it's nice that they do a follow up, but often they have completely ignored all the advice.