Be aware this work is only for reasonably competent people. Connections must be sound, as dangerous otherwise. I recommend a professional for a decent job.
6kW is 25A - apply diversity, 14.5A
Why does he need 45A cable?
In this instance, a conservative rating of what you were advising.What's 45A cable?
No, but cables buried in the wrong place have been known to lead to death, so even though you didn't install it, this really is a case of you shouldn't consider not changing it if it's wrong.Note! I did read the wiki article. I didn’t install anything that is currently there.
Installing a back box would be preferable - those JBs may not take 3 cables neatly, whereas the twin outlet plate is designed to do just that.That twin cooker outlet you were shown is ONLY suitable if it has a back box fitted to the wall. Which you don't appear to have, unless it's hidden somewhere.
Alternatively, use a 60 amp junction box, which are usually an oval shape. Click make them.
Would you have a diagram of how to wire a black box and the twin cooker outlet? Or even a link to buy a black box?
Be aware this work is only for reasonably competent people. Connections must be sound, as dangerous otherwise. I recommend a professional for a decent job.
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