Advice regarding single oven and hob

[avoman]

Hi i have a belling hob that is rated at 6.3kw and getting a bosch single oven .Oven manual states it should be on 16a it is 2.35kw it says not to use a 13a plug.

My cu has it's own cooker circuit which has a 40a fuse fitted .Theres a CCU on the wall within 2m of where both will be .And theres an outlet plate (dual outlet plate 45a click plate) behind where the oven would go.The hob is fitted to the outlet plate using 6mm2 t&e can i just connect the oven using 6mm2 t&e from the outlet plate to the oven an class them both as one cooker ?

Thanks

 

[Engineer54]

Yes, you can and should use the existing dual connection outlet plate... You can also change out the MCB/RCBO for a 32A if you wish too...lol!! The oven can be connected using 4mm if you wish, 6mm is is a bit of an over kill for just 2.35KW...

 

[avoman]

Thanks for the quick reply i think i may leave the mcb at 40a just incase i ever upgrade lol.I have some spare 6mm2 so will use it rather than buying 4mm2.Anyway would 4mm be a little underated for a 40a mcb as 4mm2 carries around 35a does it not ?

 

[avoman]

double post lol

 

[Engineer54]

Not if you changed the MCB to 32A!!

Also, your oven (or hob come to that) can't overload, so 4mm would be fine in either circumstance...

 

[avoman]

quote Not if you changed the MCB to 32A!!

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ok gotch ya thanks ..will still keep it to 40a though lol .

 

[avoman]

quote Also, your oven (or hob come to that) can't overload, so 4mm would be fine in either circumstance...

Could you plaese explain why it could not overload using 4mm2 on oven with 40a breaker.I know that an oven/hob are not on full power all the time but what if there was a fault with the appliance and the appliance saftey feature did not work and an overload happened on the 4mm2 cable ,would the cable not melt first as the 40a fuse would not trip .Or am i barking up the wrong tree.

Cheers

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[Engineer54]

quote Also, your oven (or hob come to that) can't overload, so 4mm would be fine in either circumstance...

Could you plaese explain why it could not overload using 4mm2 on oven with 40a breaker.I know that an oven/hob are not on full power all the time but what if there was a fault with the appliance and the appliance saftey feature did not work and an overload happened on the 4mm2 cable ,would the cable not melt first as the 40a fuse would not trip .Or am i barking up the wrong tree.

Cheers

The protective device will/should trip on a fault condition, but neither the hob or the oven is able to create an overload condition, they have fixed max' loads.... One appliance will not affect the other, it's a bit different if the supply cable is undersized for the combined load!! Which in this case it isn't!!

 

[avoman]

AHH Thanks just wondered that's all ..you have have been very helpful .:smilewinkgrin:

 

[avoman]

One last question is there any where that tells you the max load of t&e cable that is just hanging down at the back of the oven/hob etc as this would not come under being clipped would it ?..would it be classed as free air ?..Just curious that's all to what amperage is for 6mm2 and 4mm2 fixed like this about 2m in lenght.

 

[Engineer54]

Look up the method types and pick the nearest one!! lol!! Nothing to worry about, your over thinking things now!!

 

[avoman]

Ok i was not worrying as i am fine about the connection of my hob/oven now lol i just got intrigued about electrics and was just learning a little more about cables.I will have a google about and educate myself a little more as i like to learn new things.

 

[diditrain]

Don`t forget to look in the manufacturers instructions as to the type of cable that they recommend you use

 

[EastAnglian]

The protective device will/should trip on a fault condition, but neither the hob or the oven is able to create an overload condition, they have fixed max' loads.... One appliance will not affect the other, it's a bit different if the supply cable is undersized for the combined load!! Which in this case it isn't!!

The cable MUST be selected according to the rating of the protective device, In - not the anticipated load.

Why? Under fault conditions current up to the rated current of the protective device MAY be drawn through that cable. An extreme fault condition is a nail through the cable, but a shorted turn on a heating element is a more subtle yet possible fault which would result in higher current than when operating normally.

Therfore, to re-iterate .... Select the cable in accordance with the protective device and any rating factors which result for the planned installation method. 40A MCB and 4mm T&E .... not a winning combination!

 

[malcolmsanford]

I seem to be following you around EA, and I think it is needed.

The advice that E54 gave is absolutely spot on may I suggest you read reg 433.3.1 (ii) which in this case is appropriate to the situation.