Sanity Check Required - Do I really need 3 Phase Upgrade?

[JohnW2]

you might still have the option of getting a 3-wire 240/480V service to distribute the load though.

480V!? 230v x 1.732 = 400V OR 240v x 1.732 = 415V

Yes, but 240V x 2 = 480V. Paul was talking about a 240-0-240 three-wire 'split phase' supply (which people don't like me calling '2-phase', even if that's what BS7671 now calls it!) which still exists in some places in the UK and which is analogous to thy 120-0-120 supply which I believe is very common in the US.

Kind Regards, John

 

[ban-all-sheds]

You were complaining in another thread about how it was inconceivable to think that a designer would design a 20A radial circuit if there was a possibility of the load exceeding that.

Was I ?

Sure about that ?

But I can't find it now.

I wonder why.

 

[RF Lighting]

red & white phases, another on red & blue, and a third on white & blue.

They are not standard colours for the UK; Used to be Red (1st L), Yellow (2nd L) Blue (3rd L) and Black (N), now it is Brown (1st L), Black (2nd L) and Grey (3rd L) and Blue (N)

They used to be! Red, white and blue (how patriotic!) were permitted as standard colours for three phase supplies up until 1966. They can often still be found in some old factories etc.

Going back even further, we used to have red, blue and green phase, not to mention the black earth wires....

 

[JohnW2]

deleted

 

[JohnW2]

Going back even further, we used to have red, blue and green phase ...

You don't even have to 'go back' - as I've illustrated before, you only have to come and look at my installation! ...

Untitled

• JohnW2
• 13 Aug 2011
• 5

Kind Regards, John

 

[philnixon]

A slight update for you, apparently there is a 6mm cable for each oven - yep that's 4 separate feeds back to the fuse board. So I can see how the 22 ways are adding up!

 

[JohnW2]

A slight update for you, apparently there is a 6mm cable for each oven - yep that's 4 separate feeds back to the fuse board. So I can see how the 22 ways are adding up!

Quite so - but, IMO, that's verging on the ridiculous. Four separate feeds is quite unnecessary and, even if one decided for some reason to have them, 2.5mm² cable would probably (and 4mm² certainly) be adequate for each of them!

Kind Regards, John

 

[flameport]

Either:
a. this electrician has previously only done industrial work, where 1 circuit per machine would be fairly typical
b. they intend to make the job as expensive as possible
c. they have no idea what they are doing

 

[ban-all-sheds]

Hands up anyone who still thinks the "electrician" has the first idea about how to do the job which he thinks he is entitled to be paid to do?

 

[securespark]

Was I ?

Yes, you were.

Sure about that ?

99% certain.

But I can't find it now.

I wonder why.

Because I can't remember which thread it was.

Are you denying you ever wrote anything about that?

Or can you remember what you wrote?

 

[ban-all-sheds]

Was I ?

Yes, you were.

Doubt it.

Sure about that ?

99% certain.

That'll be "No", then.

Are you denying you ever wrote anything about that?

I'm not denying that I ever wrote anything related to that subject.

But I am denying that I said what you seem to think I did. But feel free to show that I'm wrong in that.

 

[eveares]

Going back even further, we used to have red, blue and green phase, not to mention the black earth wires....

Well that I did not know!, however I do recall the non harmonised 2nd Yellow phase used to be white as has been said.

which people don't like me calling '2-phase'

Becuase it's not!; One can not call it 2 phase without then being 180° out of phase from each other. Phase count ÷ 360° = Phase degree ofset.

Back to the OP/philnixon, I would seriously consider getting a different electrician in.

 

[JohnW2]

Either:
a. this electrician has previously only done industrial work, where 1 circuit per machine would be fairly typical
b. they intend to make the job as expensive as possible
c. they have no idea what they are doing

... or any two of the above
... or all three of the above

Kind Regards, John

 

[JohnW2]

Hands up anyone who still thinks the "electrician" has the first idea about how to do the job which he thinks he is entitled to be paid to do?

What's this "still"?? Has anyone, from my very first post onwards, ever suggested that?

Kind Regards, John

 

[PBC_1966]

They used to be! Red, white and blue (how patriotic!) were permitted as standard colours for three phase supplies up until 1966.

Yes, I chose to write red/white/blue as many of the d.c. to a.c. conversions were carried out during that era, but some would have been done after white changed to yellow.

Not that the electricity boards necessarily followed immediately, but the change for installations in the IEE Regs. specified yellow after 1st August 1964. White continued to be permitted for flexible cords & cables to 1st April 1971.

From 13th edition as amended to 1963, original 14th edition 1966, and revised 14th edition 1970:

Yes, but 240V x 2 = 480V. Paul was talking about a 240-0-240 three-wire 'split phase' supply (which people don't like me calling '2-phase', even if that's what BS7671 now calls it!) which still exists in some places in the UK

Yes, 240/480V systems are still not at all unusual in rural areas; I can think of at least half a dozen such systems within a few miles of where I used to live. The majority of homes get a standard 2-wire 240-volt connection, but for exceptionally heavy loading you could bring in both poles of the supply on a 3-wire service, just to balance the load.

which is analogous to thy 120-0-120 supply which I believe is very common in the US.

Indeed, it's been the standard supply system for residential and light commercial service for many decades, except that here it's the norm for all properties to get the full 3-wire service so that heavier loads within the building can operate on 240V.