do manufacturers apply diversity on their product info lables

[Adie moore]

woh, long title, sorry. I ask because I have never clamped a cooker circuit before. I did yesterday, hob was labeled 6ka and when all 4 rings were on full, from cold, it pulled 31a for a good 5 minutes till the thermostats started kicking in. all well within the constraints of cable, but not very good if you were edging you bets with calcs.

cheers, adie

 

[Wilko]

I thought your test should be it, the max demand. And so it's really 7kW hob. I think they're a bit cheeky !

 

[The Ghost]

6 thousand amp hob eh? very expensive to run.

 

[Marvo]

I'm guessing kA is a typo in your post, obviously 1kA is a thousand Amps.

No, manufacturers should not apply 'diversity' when stating energy consumption of appliances, they should state the maximum value. Even using some fairytale harmonised voltage of 230v, 31Amps is over 7kVA. Not sure where they got 6kVA from, have you got a photo of the info plate maybe?

 

[Andy78]

Manufacturers will not apply diversity to their total load ratings, but will apply it in their connection information if applicable.

 

[Adie moore]

ah yes, I ment 6kW. no photo I'm afraid.

 

[Besoeker]

6 thousand amp hob eh? very expensive to run.

Get your dinner ready in a millisecond...........LOL

 

[Taylortwocities]

Many manufacturers aren't even helpful with the power ratings. All they often give you is a kWh figure, yeah helpful that..

 

[Besoeker]

Many manufacturers aren't even helpful with the power ratings. All they often give you is a kWh figure, yeah helpful that..

I must admit I've never seen that. Mostly I've dealt with motors and drives rated in kW, and transformers rated in kVA or sometimes in VA. How can the manufacturer give a kWh figure without knowing the loading and duty cycle for the application?

 

[HandySparks]

I must admit I've never seen that. Mostly I've dealt with motors and drives rated in kW, and transformers rated in kVA or sometimes in VA. How can the manufacturer give a kWh figure without knowing the loading and duty cycle for the application?

With something like a fridge, you'll get an energy consumption figure in kWh/year. A washing machine may have energy use per cycle in kWh. So more use in estimating running costs than sizing a supply.

 

[Besoeker]

With something like a fridge, you'll get an energy consumption figure in kWh/year. A washing machine may have energy use per cycle in kWh. So more use in estimating running costs than sizing a supply.

It can only be a loose estimate at best and depend on many factors.

 

[Besoeker]

With something like a fridge, you'll get an energy consumption figure in kWh/year. A washing machine may have energy use per cycle in kWh. So more use in estimating running costs than sizing a supply.

With so many factors involved you'd get, at best, a very loose estimate.

 

[HandySparks]

It can only be a loose estimate at best and depend on many factors.

Yes. I assume that there are standard test conditions for this. A bit like mpg figures for cars; not necessarily what you'll get in the real world, more a means of comparing appliances.

 

[Marvo]

I don't think it would be even remotely possible to work backwards from the annual consumption figures to a load current.

 

[Wilko]

I don't think it would be even remotely possible to work backwards from the annual consumption figures to a load current.

Agree, like trying to reverse engineer a duck

 

[Taylortwocities]

Mostly I've dealt with motors and drives rated in kW, and transformers rated in kVA or sometimes in VA. How can the manufacturer give a kWh figure without knowing the loading and duty cycle for the application?

I blame the Europeans!
Here's the European Data Sheet giving the EU required information for a typical NEFF oven.
Download EU Data Sheet

oCare to guess the power requirements?

Sometimes, it is possible to find the loading from a supplier's web site. Often one has to wait for the bloomin thing to arrive so you can read the rating plate. The wiring work is usually all done long before then.