4.5kw on 30a cooker

[Iona222]

Just installing this for a friend. 4.5kw ÷240. Minus 30% is that right.

 

[Lucien Nunes]

What is your specific question? If it's 'How is diversity applied to a domestic cooker rating?" then no, it's not right.

 

[littlespark]

4500/ 230v is less than 20A so a 30A supply is fine.

however you still need to check cable size? rcd protection?

 

[timhoward]

OP - for next time when the appliance is bigger I've set out the diversity calculation for a 4.5 Kw cooker below. It's certainly the most confusing one.
Full load current: (4500/230)= 19.57amps
Set aside the first 10 amps, and work out 30% of remainder
9.57 amps x 0.3 = 2.81 amps
Add the first 10A back = 12.81 amps if no socket on switch
If there's a socket on the plate add 5 amps. 17.81 amps if it has socket

So when adding up maximum demand of the house you'd use the appropriate value.

 

[i=p/u]

was just reading this ..

 

[timhoward]

For a long time I didn't have the on site guide. I finally relented a year or two ago and I'm still not sure it's worth the money. I favour the ProCerts apps for most things, and the OSG omits some useful tables for current carrying capacity of some cable types.
That page @i=p/u posted, and the couple before it are probably the only pages I use in it most of the time.

 

[brianmoooore]

That table's been around a while. It's Appendix 1 in the 14th edition of the regs., which is as far back as I go.

 

[Iona222]

That table's been around a while. It's Appendix 1 in the 14th edition of the regs., which is as far back as I go.

14th edition omg. Your showing your ages mate.

 

[brianmoooore]

Feeling it as well!
14th is 224 pages of A5 paper, cost £1.25, and best of all, it can be read like a normal book. Sections A to K, with each reg. numbered sequentially, starting from 1, with 8 short appendices at the back.

 

[MJPD29]

Just installing this for a friend. 4.5kw ÷240. Minus 30% is that right.

No