230V/240V Question

[securespark]

It was but, in my experience, ovens do get a bit warm.

I find they get warmer if the number on the dial is bigger.

 

[winston1]

Thus they changed the specification on paper without requiring any physical changes on the network.

That's true but it did allow standardisation of calculations and related value tables.

But it means that the calculations are now wrong.

 

[ban-all-sheds]

I assumed it was a joke.

No - that's Winston.

 

[333rocky333]

I assumed it was a joke.

No - that's Winston.

thats not very nice Bas, its xmas

 

[ban-all-sheds]

The change in the 1990's was an exercise in juggling the specified nominal voltage and permissible tolerances for the political expediency of being able to claim "harmonization" with Europe,

In what way was that "politically expedient"?

the result being a declared nominal voltage 230V but with an odd asymmetrical tolerance of +10/-6%, a range of 216.2 to 253 volts.

The result being that if you wanted to sell electrical equipment in Europe it had to be able to tolerate the voltage range across Europe.

 

[PBC_1966]

The change in the 1990's was an exercise in juggling the specified nominal voltage and permissible tolerances for the political expediency of being able to claim "harmonization" with Europe,

In what way was that "politically expedient"?

To be able to claim that the U.K. had adopted a European standard without actually doing anything except juggling with the tolerances.

the result being a declared nominal voltage 230V but with an odd asymmetrical tolerance of +10/-6%, a range of 216.2 to 253 volts.

The result being that if you wanted to sell electrical equipment in Europe it had to be able to tolerate the voltage range across Europe.

Which it already had to anyway, before the change. So what?

 

[ban-all-sheds]

To be able to claim that the U.K. had adopted a European standard without actually doing anything except juggling with the tolerances.

But that's all it was anyway - nominal ±%.

Are you in the Winston camp of not understanding what the word "nominal" means?

Which it already had to anyway, before the change. So what?

No it did not - if a maker chose not to support a particular range he did not have to.

 

[PBC_1966]

Are you in the Winston camp of not understanding what the word "nominal" means?

I know perfectly well what it means. But leaving everything on the network as 240V +/-6% while saying "Ah, but we'll call it 230V +10/-6% now" was still nothing more than a mathematical juggling act to claim compliance with the new 230V European standard.

No it did not - if a maker chose not to support a particular range he did not have to.

If he wanted to be sure of it working in other parts of Europe he did, which is the point to which I was responding:

The result being that if you wanted to sell electrical equipment in Europe it had to be able to tolerate the voltage range across Europe.

 

[ban-all-sheds]

But leaving everything on the network as 240V +/-6% while saying "Ah, but we'll call it 230V +10/-6% now" was still nothing more than a mathematical juggling act to claim compliance with the new 230V European standard.

I think you need to spend more time trying to understand basic arithmetic.

No it did not - if a maker chose not to support a particular range he did not have to.

If he wanted to be sure of it working in other parts of Europe he did, which is the point to which I was responding:

The result being that if you wanted to sell electrical equipment in Europe it had to be able to tolerate the voltage range across Europe.

I did not say if he wanted to be sure of it working, I said if he wanted to sell it. There was EU legislation which meant that he HAD to make it compatible with the harmonised voltage standard.

 

[PBC_1966]

I think you need to spend more time trying to understand basic arithmetic.

What's wrong with my arithmetic?

240V +/-6% equates to a range of 225.6 to 254.4 volts.

230V +10/-6% equates to a range of 216.2 to 253 volts.

As I said, the new specification encompasses all of the old range except for that 1.4V at the upper end, into which excursions were pretty rare anyway.

I did not say if he wanted to be sure of it working, I said if he wanted to sell it. There was EU legislation which meant that he HAD to make it compatible with the harmonised voltage standard.

There was talk of widening the tolerance to +/-10% at one time, but last I heard that had been abandoned. Was there an EU directive based upon 230V +/-10%, and if so, did that get transposed as is into U.K. legislation, or with changes?

 

[ban-all-sheds]

What's wrong with my arithmetic?

It was your comment about the "mathematical juggling act" which concerned me.

If you have a supply voltage which ranges between V1 and V2, then any nominal figure ± is as valid as any other. 240V +/-6% while saying "Ah, but we'll call it 230V +10/-6% is no more, or less, of a mathematical juggling act than 240V ±6%. Winston has the same attitude - he seems to think that one nominal value within the range is correct and all the others are incorrect.

There was talk of widening the tolerance to +/-10% at one time, but last I heard that had been abandoned. Was there an EU directive based upon 230V +/-10%, and if so, did that get transposed as is into U.K. legislation, or with changes?

Voltage harmonisation was a CENELEC thing (Harmonisation Document HD472), but the way it was (is?) to be made practical reality was to require equipment to tolerate the entire range. Not really a problem except for incandescent lamps.

 

[PBC_1966]

It was your comment about the "mathematical juggling act" which concerned me.

Obviously if you adjust the permissible tolerances you could declare it to be anything within that range if you wish: 235V +8 / -8%, 250V +1.2 / -13.5%, etc.

But if an asymmetric tolerance is to be considered acceptable and they wanted to expand the permissible range downward, they could just as easily have declared that henceforth it would be 240V +6 /-10% in place of 240V +/-6%. It's abundantly obvious that the only reason for deciding to call it 230V +10/-6% was to claim adherence with a new 230V "Euro" standard on paper.

 

[EFLImpudence]

It was - but the related values (max. Zs etc.) were adjusted to be compatible with 230V therefore continued use of 240V would not give the correct answers.

It really doesn't matter so is not worth disputing.

The same as metrication - I am now 1.83m tall but have not shrunk.

 

[PBC_1966]

It was - but the related values (max. Zs etc.) were adjusted to be compatible with 230V therefore continued use of 240V would not give the correct answers.

But if they hadn't changed the declared nominal voltage, the tables wouldn't have been recalculated for 230V, surely?

As you say, it's not a huge difference and there's plenty of "wiggle room" built in anyway, but that just goes to emphasize how unnecessary it was to mess around with the supply specification. The intent was, ultimately, to achieve the situation in which appliances are designed to work on 230V +/-10%. All but that odd volt-and-a-bit at the upper end of 240V +/-6% was already within that range, so there was absolutely no need to change it other than for usual case of "European harmonization" for the sake of it.

 

[EFLImpudence]

so there was absolutely no need to change it other than for usual case of "European harmonization" for the sake of it.

Agreed - but harmonization was the reason and purpose.

What would have been silly was claiming harmonization and having different values.