Connecting Appliances

[Raymat]

What is the best way to connect a 5.9kw hob and a 3kw single oven. Still waiting for delivery of hob but oven info states to be fused at 15amp minimum 20amp maximum.

 

[jj4091]

You do not give enough info to advise on, you would probaly be best off calling someone in.

 

[Raymat]

Sorry for not giving enough info so I'll try again. The hob is rated at 5.9kw max, the oven is rated at 3kw. There is a 45amp cooker connection point wired with 6mm cable. The general opinion is a 3kw oven can be plugged into a 13amp socket however the booklet states the oven should be fused at 15amp min 20amp max into a d/p connection unit. Can I connect from the cooker point with 6mm cable to the hob. Can I then spur from the cooker point into a 20amp fused d/p connection unit and connect to the oven. The cable from the consumer unit as I said is 6mm and the length is approx 6 metres. The oven will then be fused at 20amps and the whole lot protected by a 40amp mcb.

 

[jj4091]

3KW @ 230V is 13A, so you should be ok with a 13A switched spur off the CCU, as the 6mm cable & cooker switch is ok for the load of the oven & hob, but you are always recommended to follow the manufacturers instructions.

 

[GaryMo]

3KW @ 230V is 13A, so you should be ok with a 13A switched spur off the CCU

It's actually slightly over 13A, not much but it's still over hence the reason the oven manufacturer suggests overload protection between 15 and 20A.

 

[jj4091]

3KW @ 230V is 13A, so you should be ok with a 13A switched spur off the CCU

It's actually slightly over 13A, not much but it's still over hence the reason the oven manufacturer suggests overload protection between 15 and 20A.

It must depend how you calculate it this http://www.tlc-direct.co.uk/Technical/Charts/OhmsLawCalculator.html says 13 or 12.5 @240v

 

[ban-all-sheds]

It must depend how you calculate it

Well of course it does.

3000 ÷ 230 = 13.04 (so "slightly over" is a bit strong for 0.3%)

3000 ÷ 240 = 12.50

In the absence of any other info you're supposed to use 230V, which will exaggerate the load if the manufacturer has quoted it's rating at 240V - a 3kW@240V appliance will actually draw 11.98A at 230V (ignoring any changes in load characteristics due to temperature).

But a 3kW@230V appliance will draw 14.35A at 253V (again ignoring temperature effects).

 

[GaryMo]

3000 ÷ 230 = 13.04 (so "slightly over" is a bit strong for 0.3%)

Very slightly over then, any better?
In any case at 230v it's over 13A.

 

[sijaysee]

but you dont know if his oven is rated at 3kw @ 230v or
3kw @ 240v

btw my kettle is 3kw