Oven and hob on same MCB and diversity.

[Lucien Nunes]

But Y is the symbol for admittance, the reciprocal of impedance (Y=1/Z). Many capital letters stand for quantities and should not be used generally.

Its very often possible to distinguish 0.3I from 0.31 automatically by context (0.3I has dimensions of current but 0.31 is dimensionless.) However if an explicit multiplication symbol is needed to avoid ambiguity or for visual clarity, there is a choice of the asterisk * (from ASCII-based programming) or a full stop aka period or centre dot which is the conventional algebraic symbol to use on paper. Conventions that use the centre-dot for decimal fractions theoretically use the period for multiplication and vice versa. I would understand 0.3I, 0⋅3.I, 0⋅3*I etc as equivalent. In vector algebra the two multiplication operators ⋅ and x signify different operations, but again it would be clear from context that the distinction doesn't apply here.

 

[Midwest]

I've not read through thoroughly all the replies, but when I was calculating diversity for two appliances, I would use two calculations. With one free standing, it would be one calculation.

I based my rational on that the later are sometime supplied with a plug, with very simple cooking activity and the former could have multiple zones for a hob and two or three or more zones for the oven part. Much more cooking activity.

That said, I once had a Range style electrical cooker, which had 3 ovens, manufacturer required 40A supply. With all three ovens going at full pelt, never pulled more than 14A.

 

[Lucien Nunes]

Ours only has two ovens but with both of those on, the grill, all four rings and the lights, it uses about half an amp.

 

[pc1966]

Ours only has two ovens but with both of those on, the grill, all four rings and the lights, it uses about half an amp.

Half an amp? Have you got on of those 11kV cookers?

 

[telectrix]

Ours only has two ovens but with both of those on, the grill, all four rings and the lights, it uses about half an amp.

obviously it's gas or youse fiddled the meter.???

 

[Lucien Nunes]

The burners are gas, yes, but for some reason the clock, lights and rotisserie are electric.

 

[Mike Johnson]

I wonder who decided in the EU to use a comma instead of a period between the € and C, i.e in €3,00?

 

[pc1966]

I wonder who decided in the EU to use a comma instead of a period between the € and C, i.e in €3,00?

It is common in France and Germany (at least) to use the 'point' as a thousands separator and the comma as the decimal place, opposite to our convention. Why it turned out that way I have no idea...

 

[Midwest]

It is common in France and Germany (at least) to use the 'point' as a thousands separator and the comma as the decimal place, opposite to our convention. Why it turned out that way I have no idea...

Too many frogs legs and too much sauerkraut methinks ?

 

[HappyHippyDad]

I realise we have come to the end if this thread, however.... as coincidence happens a slightly different yet similar scenario has arisen.

The customer wants 2 x separate single ovens next to each other with an induction hob above.

The previous answers in this thread suggest treating a separate hob and oven as a single appliance with regards diversity, and I can see that makes sense. We can't just keep adding an appliance on and classing it as one unit though, as single units have thermostatic controls. How would you apply diversity in this case? I'm inclined to use my initial maths here and class it as 2 appliances.

 

[stevethesparks]

Generally I would use two circuits. However, as they have two ovens, it may suggest they do a lot of cooking/baking, so if not too far a run I might also consider 3 circuits.

 

[Mike Johnson]

The burners are gas, yes, but for some reason the clock, lights and rotisserie are electric.

I bow to your superior knowledge on all of these things, but can you get gas clocks, light and rotisserie these days, I know about gas lights, but? ?

 

[Midwest]

I realise we have come to the end if this thread, however.... as coincidence happens a slightly different yet similar scenario has arisen.

The customer wants 2 x separate single ovens next to each other with an induction hob above.

The previous answers in this thread suggest treating a separate hob and oven as a single appliance with regards diversity, and I can see that makes sense. We can't just keep adding an appliance on and classing it as one unit though, as single units have thermostatic controls. How would you apply diversity in this case? I'm inclined to use my initial maths here and class it as 2 appliances.

I didn’t agree with that concept myself; I treated individual appliances separately when apply diversity, for the reasons you’ve now been presented with.

 

[Paul508]

This Math looks wrong to me, forgetting the incorrect use of Q,

Incorrect
2 x (10A + 0.3Q) = 32A

20A + 0.6Q = 32A

0.6Q = 12A

Q = 20A

Correct

2 x (10A + 0.3Q) = 32A

20A + 0.6Q = 32A

32A - 20A = 12A

100% of the remaining = 12A

Therefore 60% of the remaining = 7.2A

Value of Q = 7.2A

Circuit then has a 4.8A buffer

Then if you actually take into account load 32A is more than sufficient

 

[123]

This Math looks wrong to me, forgetting the incorrect use of Q,

Incorrect
2 x (10A + 0.3Q) = 32A

20A + 0.6Q = 32A

0.6Q = 12A

Q = 20A

Correct

2 x (10A + 0.3Q) = 32A

20A + 0.6Q = 32A

32A - 20A = 12A

100% of the remaining = 12A

Therefore 60% of the remaining = 7.2A

Value of Q = 7.2A

Circuit then has a 4.8A buffer

Then if you actually take into account load 32A is more than sufficient

This is wrong also though. Q is actually a known value determined by the appliance(s), the 32A is the unknown value which needs to be worked out via calculation.

 

[HappyHippyDad]

Oh dear.

Now Lucien will see it (the ill placed and brazen ) again and get cross with me... again

 

[pirate]

The use of a comma as a separator is not unusual, and as one doesn't usually work in a bilingual situation, it seldom causes confusion. What does confuse me quite often is that the arroba key (@) is in different positions on the keyboard depending on the country you are in at the time, assuming one is using a "local" keyboard of a physical nature...but then, I am easily confused!