Cooker wiring WTF

[normspanners]

Diversified load and diversification factor[edit]
The diversified load is the total expected load (power) to be drawn during a peak period by a device or system of devices. The diversified load is the combination of each devices full load capacity, Utilization Factor, Diversity Factor, Demand Factor and the Load factor(electrical)|load factor. This process is referred to as load diversification. The diversification factor is then defined as:

 

[mike os]

That's how I think norm....For me 6mm and 10mm from the board

 

[sparkysy]

And the voltage will make a difference to the total load too! Do you have a clamp meter? If so turn it all on and see what's being pulled!

 

[normspanners]

Right I have now found this,
go to page 12 it seems to be the exact same manual, but read this, section on cable sizing that is not in the manual I got from BEKO it says cable must be 6mm!!!!

http://downloads.beko.co.uk/bekoupload/manuals/DC643.pdf

 

[Robotstar5]

Just to be on the safe side then get some 25mm² welding cable

 

[Robotstar5]

Sorry I dont understand this diversity theory as when you start cooking you could put all the hob and oven on to warm up...

Does this help?

 

[normspanners]

Thanks for that it just seems to make a mockery of all the other regs, that say you need massive cables for this and that yet when an appliance that can draw so much power for so long is allowed a small cable but then states but be generous with cable and fuse ratings!!
plus stating that a 3kw kettle might also be plugged in so add 5A!!

quote
The diversity applicable to the current demand for a cooker is shown in {Table 6.2} as 10 A plus 30% of the remainder of the total connected load, plus 5 A if the control unit includes a socket outlet. A little thought will show that whilst this calculation will give satisfactory results under most circumstances, there is a danger of triggering the protective device under some circumstances. For example, at Christmas it is quite likely that both ovens, all four hotplates and a 3 kW kettle could he simultaneously connected. Just imagine the chaos which a blown fuse would cause! This alone is a very good reason for being generous with cable and protective ratings.

 

[brightspark]

Just to be on the safe side then get some 25mm² welding cable

even go 30mm why not just to be extra sure i dont know why we have all these tables regs and the use of diversity when some folk think its not aceptable to do so and go ott with everything they do .if u dont fully understand it dont touch it

 

[normspanners]

even go 30mm why not just to be extra sure i dont know why we have all these tables regs and the use of diversity when some folk think its not aceptable to do so and go ott with everything they do .if u dont fully understand it dont touch it

Well it is obviously NOT clear even to the manufacturer when one manual says 2.5 then another manual for the same cooker reads exactly the same and that manual says 2.5mm in the spec's table and a few pages down it then says 6mm
could that be explained please??
So you are saying that my first conclusion of 6mm was wrong and ott?

 

[brightspark]

the majority of cookers ovens and hobs are configured for the european markets and can be wired for 3 phase or single phase by altering the links. please note the 3 phase is only @110v each phase abroad not 240v .by linking all 3 phases and using the neutral terminal they can be wired for single phase 2 wire and earth . wiring for the 110v 3 phase only 1.5 or 2.5 is required to each phase . linked for uk 240v single phase a 6,0mm would be required. i didnt mention anyones post and 6mm will be fine on 99 percent of cookers allowing for diversity .u wouldnt be even able to get any bigger cable in due to the connection plate termnal size .all i pointed out was u dont need a bigger cable to supply the cooker just because of its total load and maybe over 12kw . a fixed load of 9.5 kw must be on a larger cable as the load is constant . there is N0 Diversity as in a cooker

 

[Monkey Harris]

Thanks for that it just seems to make a mockery of all the other regs, that say you need massive cables for this and that yet when an appliance that can draw so much power for so long is allowed a small cable but then states but be generous with cable and fuse ratings!!
plus stating that a 3kw kettle might also be plugged in so add 5A!!

quote
The diversity applicable to the current demand for a cooker is shown in {Table 6.2} as 10 A plus 30% of the remainder of the total connected load, plus 5 A if the control unit includes a socket outlet. A little thought will show that whilst this calculation will give satisfactory results under most circumstances, there is a danger of triggering the protective device under some circumstances. For example, at Christmas it is quite likely that both ovens, all four hotplates and a 3 kW kettle could he simultaneously connected. Just imagine the chaos which a blown fuse would cause! This alone is a very good reason for being generous with cable and protective ratings.

A good point ...
but in reality.....how many people loose there cooker circuits on Xmas day...
I'm a sparks and repair ovens. I've seen none in 6 years.

 

[brightspark]

[ive done well over 1.000 callouts and on christmas days. in 15 years there hasnt been a lot of burnt out cooker circuits maybee half a dozen on christmas day .a couple of burnt out cooker controll units due to loose wires and a few oven elements broken down and trippng the rcd along with faulty rings on top

 

[wookie]

obviously you could not combine three phase to one x2 terminal block, that would just blow all three fuses.
it seems crazy to list it as an option.

Because some cookers can be wired to a 3 phase supply. I think the plate on yours is wrong for your cooker.

Here's the wiring diagrams from my cooker (it's a different make but it's just to illustrate a point), it's a twin oven and separate grill so 3 heating elements...

First the installation diagram

And the actual circuit diagram showing how the individual elements can be on separate phases...

But I agree with you Norm, really it should just say minimum Xmm and 'Only to be installed by a qualified electrician'

I don't know if you are a qualified electrician Norm, that's beside the point, but the manual you linked to gives different information to the plate you quote. Stuff like this is confusing and potentially dangerous as someone who isn't qualified can easily mis-read it as only needs 1.5mm cable to supply the cooker, where as you would hope an electrician would realise and wire it up accordingly.

 

[brightspark]

as said above some of these instruction manuals can be confusing due to the voltages and configuration . nearly all manuals say if unsure get a qualified electrician and adhere to regulations. so if anything goes wrong they have covered themselves and the onus is on you , i even know some electricians that cant understand them

 

[normspanners]

Here's the wiring diagrams from my cooker (it's a different make but it's just to illustrate a point), it's a twin oven and separate grill so 3 heating elements...

I totally understand that instruction manual,
BUT look at the feed cable sizes 6mm and 10mm for 1ph
and as I meantioned earlier in post 27 regarding 3ph the neutral would need to be larger as shown on your diagram = 10mm to take the total neutral return

Thanks guys these are two screen shots from the last manual I found, to me, it is very confusing A person
that just looked at the spec sheet without checking how to actually wire it would fit the wrong cable?
How many professionals would think to look at a map of where to put wires in a simple 3 terminal block

 

[Big Pete]

That plate says 3 x 2.5mm^2 conductors, so total CSA = 7.5mm^2, and may well run cooler than a 6mm^2 cross section. PITA to wire up though, running three cable runs to the cooker, but it will do the job, same for 5 x 1.5mm^2 cross section.

 

[brightspark]

the feed to the apliance needs to be 6mm twin and earth it does not need a 10mm neutral the total l;oad for the full apliance is only 9.9kw i give up just carry on folks

 

[normspanners]

I don't know if you are a qualified electrician Norm,

No I am not, but have over the years wired and overseen many industrial applications workshops etc
working with and learning from some in my opinion very good industrial electricians and electonic engineers, not just (sorry but there are some) wire fitters. Who if asked an intelligent question about a simple item by a non electrician, if they cannot answer go down in my estimation.
I think I have a fair idea of electrical installations and I do not regard myself as stupid in these matters.
my main concern is usually on the safety aspect which these manuals dont seem to follow.

 

[Big Pete]

Whats unsafe? Unless I missed something the rating plate in the first post specs a 7.5mm^2 cross section for the wires?

 

[normspanners]

the feed to the apliance needs to be 6mm twin and earth it does not need a 10mm neutral the total l;oad for the full apliance is only 9.9kw i give up just carry on folks

If you read the diagram in post 58 it stipulates 10mm input for single phase
and for 3ph 6mm for the inputs and 10mm neutral which is exactly what I said in post27
Why would it say on the wiring diagram 10mm? if not needed?