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Hey Everyone, It's the 1.5mm cable protected by a 10A MCB as in my other thread (however it's locked now so can't update it). A 50% de-rating of 1.5mm is 10A, so I'm probably still ok? Thanks

Hey Everyone, Regarding CCC table for cable rating, would placing a cable over a suspended ceiling, covered in insulation be the same rating as placing a cable over a plasterboard ceiling covered in insulation? I understand that the materials are different (suspended ceiling being mineral...

Perhaps you should ask yourself why you find it weird that someone just likes to understand what is going on around them. I take interest in what my contractors do, and like to remain competent in the process.

Ok, this is my last post to you ban-all-sheds. That is not what I said. That is you changing my words. I'm not sure you are aware of this, but there is more than 1 law in most countries. There are many other laws that ensure safety in the workplace. What's funny though, is that for a...

I don't see anywhere where anyone has even implied that, never mind said that directly.

Thanks John :) I'm not doing the work myself actually. I just want to be able to understand the work someone else is doing for me. He is registered with the NICEIC, but I still want my own understanding to be on the safe side :) Don't want anyone pulling the wool over my eyes.

Incidentally, is the table available online somewhere where I can see the 13A figure? Also, when you talk about "some kinds of fuses", is that in reference to rewireable fuses in the CU (instead of MCB), or do my 5A fused switches (in line with each heater) mess the calculations up? Thanks

Now where did you get that from? Obviously, I am here asking questions to make sure that the installation is safe, and want to understand it. I just didn't want any lectures on Part-P notifications etc as it doesn't apply to me. Thanks

That's very simple actually. I wish that was well documented online as I've been scratching my head over this for ages! I was worried that any calculated rating value would have to include the MCB over-currents. So basically, after taking into account the rating based on your installation...

Ok great! But let's say I have a hypothetical 10A cable (I know my real cable is 13A). You say that a 10A MCB would allow 11.3A indefinitely. Is that still acceptable for this hypothetical cable?

Excellent, that sums everything up nicely! How do you know what is an acceptable limited-time overload current for a given CCC? Let's take the 13A in my cable's case. What maths did you do to realise that 14.5A for 1 hour is safe? Sorry for all the questions. I'm not a spark, just very...

Thanks for the reply guys!! So a 10A MCB it is! Wow, I didn't know that the 50% was only for cable wrapped in insulation. Didn't think people really do that (I though covering with insulation was bad enough!). Just another question. The 13A cable max. How does this value compare to the...

Got it, thanks! Where did you get 13A from? I thought covered in insulation reduced the cable rating by 50%, so 10A? Also, when I say long time, even though the heaters wont overload the cable, I guess I'm just trying to protect the cable in-case someone in the future plugs in higher power...

Thanks for the quick reply folks! No, not long at all. The CU is almost touching the ceiling. The cable goes across the ceiling (about 6m), then down the opposite wall for a remaining run of about 7.5m. It would be appreciated if someone could explain why the 10A is still ok, given the...

Hi Everyone, Note: I live in a part of the UK where there is no Part P. We have a room that has electric heating (almost) installed. We have 2 X 1000W electric heaters. A single 1.5mm T&E cable is being run from the CU to the first heater fused switch (fused to 5A). Then, another 1.5mm...