UK voltages

I have a lathe which originated in the UK and requires 440 3 phase. There is an additional voltage required that goes from one leg of the

3 phase to a neutral terminal. I'm unclear how the transformers are typically wired in the UK but I'm guessing this voltage would be 270V. Is this correct? Thank you.
Reply to
bister
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Hello Bister

U.K. voltage was 415 V phase to phase, 240 V phase to neutral ( neutral at ground potential ) and it's at 50 Hz

U.K. is now harmonised with Europe on 400 / 230 supply.

Torque is de rated 17% for a 60 Hz supply, speed is + 20%

Hope this helps.

-- Jonathan

Barnes's theorem; for every foolproof device there is a fool greater than the proof.

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Reply to
Jonathan Barnes

But it hasn't really changed

240 is 'within tolerance' for the now nominally 230V supply. There were public assurances when the change was announced, that nothing was really going to change, & it certainly hasn't changed around here. Volts here (ie my premises) are usually 240 to 242.

Cheers Tim

Tim Leech Dutton Dry-Dock

Traditional & Modern canal craft repairs

Reply to
timleech

Nope, phase to neutral is 240V approximately, starting from a 440V phase to phase.

Phase to phase is less than the sum of two phases as the cycle/sine wave is 120 deg shifted between each phase to the next one. There's a formula for it...

Peter

-- Peter & Rita Forbes snipped-for-privacy@easynet.co.uk Engine pages for preservation info:

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Reply to
Peter A Forbes

Not quite. The UK 3 phase supply is nominally 440 volts Phase to Phase. This corresponds to 240 volts Phase to Neutral. I very much doubt if your lathe requires an extra voltage but most probably it has been wired in a 4 wire "STAR" connection with a Neutral. It should be possible to rewire the motor in a 3 wire, 3 phase "DELTA" connection but you really need reference to the manufacturers data.

It is, I suppose, also possible that the 240 Volts is some sort of auxiliary supply for contactors or lighting.

That is about the limit of my knowlege - others may well know more.

regards

Adrian

Reply to
Adrian D Parker

For a Three Star Balanced System:- The phase to phase voltage is the square root of three times the phase to neutral voltage.

sqrt 3 = 1.732 therefore 240 * 1.732 = 215 volts

254 * 1.732 = 440 volt

Well it was when I went to Tech School

Reply to
Maurice

Should read Three Phase Star

Reply to
Maurice

240 * 1.732 was nearer 415, not 215, when I went to school. My calculator seems to confirm that it hasn't been devalued in the intervening years ;-)

Regards, Tony

Reply to
Tony Jeffree

Poor bloke.lol. He only wanted the UK voltage.lol.lol

Reply to
Activeviii

Reply to
Andrew Mawson

I apologize it was a Typo error, I was only trying to be constructive. I wont bother next time.

Reply to
Maurice

As long as my German bolts hold my Italian motor to my English gearbox......:-)

-- Jonathan

Barnes's theorem; for every foolproof device there is a fool greater than the proof.

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Reply to
Jonathan Barnes

Mebbee you need to grow a slightly thicker skin to hang around here?

Please do bother next time, that is how we gain knowledge

Bob

Reply to
Bob Minchin

Sure its English and not imported casting from China, assembled in Czech and inspected in UK.

Dave

Reply to
Dave Jones

Having followed this thread it really gives me a warm feeling that, thanks to European harmony, all things are being standardised and if someone is going to call me a cynical b*****d I would also probably agree.

I wonder if the wall on the white cliffs of Dover (should be mid-channel unless we can claim Henry VII lost Brittany due to 'over regulation') will be built to the 'arcane' units called feet and inches.

I only use the word 'arcane' as there are very few people using Imperial. These days it is limited to North America, Canada, large parts of Russia and China.

Have a good one

Mart

In message , Maurice writes

Reply to
Martin Akehurst

Not true, we (personally and at the factory) still use Imperial dimensions quite a bit as a lot of engineering components and electrical fittings are still sized in Imperial dimensions (albeit shown in drawings as mm)

PCB components are still based on a 0.1" grid, and there are plenty of other examples I can think of... :-))

Peter

-- Peter & Rita Forbes snipped-for-privacy@easynet.co.uk Engine pages for preservation info:

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Reply to
Peter A Forbes

Not true! Canada is officially metric. It's just that we only use it if we have to, so...................... Speed limits are in KmH, liquids are in litres, but stores price meat and vegetables in KG, and pounds. I use Celsius (Centigrade) or Fahrenheit temperatures, according to whatever thermometer happens to be in a room. In short, it's a bloody mishmash!

Oh yes, there is only one metric micrometer in my workshop, a remnant from my days as a watchmaker.

Steve R.

Reply to
Udie

Down at my local Jewsons (builders merchants) I asked for some two by three timber. There was a lot of 'sucking of teeth' followed by "We don't stock that its all metric now". He converted it (50 by 75) and went off to the warehouse. He looked up and down the racks and said "Fifty by seventy five, fifty by seventy five, where is it, that's about ... ooohhh ... two by three isn't it?"

Ah metrication!

Reply to
Martin Akehurst

Martin wrote .......

Into the same Jewson's there came a farmer seeking a gate for his field. He acknowledged that things had all gone metric and asked for the gate width to be "Two metres, five inches, and my thumb."

Reply to
Mike Whittome

Udie wrote

The official SI name is Celsius. See the SI website:

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Reply to
Pat Norton

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