Cable rating for lighting circuit?

[jmhill]

Hi,

I'm wiring in lights in a loft space. I have 3 x 60w (max) lamps equally spaced in parallel on a 10m cable run. The cable will be clipped to the rafters.

I want to use 1.5mm cable but the light fittings I have will not accept cable of that size. Can I get away with 0.75mm or should I buy different fittings?

Regards,

Jon

 

[rjm2k]

Don't forget 1mm

 

[Taylortwocities]

The size of the cable that you can use depends on the size of fuse that is protecting the cable. It is not related to the size of load, or if the wires can fit in the holes.

So.. next question: what size is the fuse protecting that circuit? It may be too big for 0.75mm² conductors.

 

[OwainDIYer]

buy different fittings. If they can't accept 1.5mm conductors they must be crap.

However 1 mm on a 6A MCB will usually be adequate.

 

[ericmark]

Table 52.3 - Minimum cross-sectional area of conductors
Power and lighting circuits Material Copper Cross-sectional area 1.0 mm²
0.75 mm² is allowed as a flex for a specific appliance so from ceiling rose to lamp holder it's OK but not from ceiling rose to ceiling rose.

 

[jmhill]

Hi Thanks,

The circuit is protected by a 6a RCD.

I was going wire them together with twin core using the terminals inside the lamp, or should each one be connected to the circuit via a rose/junction box?

Cheers,

Jon

 

[EFLImpudence]

//www.diynot.com/wiki/Electrics:Lighting

 

[OwainDIYer]

The circuit is protected by a 6a RCD.

I was going wire them together with twin core

I think you mean MCB or RCBO

All fixed wiring must have a cpc (earth) wire.

 

[jmhill]

Hi,

Thanks for all the help.

As a result of the comments I have re thought the circuit.

I have found that I can fit 1x 1.5mm T&E into each lamp so I will run 1.5mm T&E to the last lamp in the chain, then use junction boxes along that run to connect the other two lamps using 1.5m T&E between each lamp and the boxes.

I'm hoping that will be acceptable.

Thanks again.

Jon

 

[Taylortwocities]

Its acceptable, but you have so much more work and complexity instead of simply using the appropriate materials. But, there's nothing wrong with using a sledghammer to crack a nut.

 

[rjm2k]

Make sure the JB's are Accessible or MF