Lighting circuit - change of wire diameter mid-way ok?

[edlewis]

Hi, I've got a 2009 built flat that came with some pendant lights and I set about replacing them with some fixed (bulb not replaceable) Aurora M7 LED downlights

I daisy-chained the new downlights to the existing feed. At the time I noticed the existing feed was 1.5mm2, though my new wire for the daisy-chaining is 1mm2. The cable runs through a suspended ceiling and isn't covered in insulation or anything

An electrician I've spoken to more recently said this wasn't a good idea, and that you should never change the diameter of the cable mid-way on a circuit.

The lighting circuit is on a 6A breaker
One set of lights has 8 x 7W lamps, the other has 6 x 7W lamps

I figured that the 1mm2 is fine for the 6A load. So is this electrician right or am I? Put another way, if I asked an electrician to sign off these minor works, would he be able to do so?

Thanks!

 

[riveralt]

1mm² T&E is fine - where is the joint (junction box?) though - because that has to be accessible.
The key point is that the current carrying capacity of the cable must be more than the MCB protecting the circuit. 1mm² T&E ccc is more than twice the 6A breaker.
Why does it need signing off?

 

[edlewis]

1mm² T&E is fine - where is the joint (junction box?) though - because that has to be accessible.

I took the old 1.5mm2 feed to the first downlight, and daisychained the 1mm2 from there

1mm² T&E is fine - where is the joint (junction box?) though - because that has to be accessible.
The key point is that the current carrying capacity of the cable must be more than the MCB protecting the circuit. 1mm² T&E ccc is more than twice the 6A breaker.
Why does it need signing off?

Thanks, that's what I thought. I was asking about sign off to make sure that it's not only theoretically ok but ok under building regs too