Downlight Cables

[zedess]

Have been called back to a kitchen lighting job i completed a few months ago,6x gu10 mains downlights on with the downstairs lighting circuit,rcd protected.Inspected my new wiring system today ..and it looks like it has been in 20years not 2 months! Customer says they have been tripping the rcd after they have been on for about 6hours...apparently they switch them on on a morning and leave them on all day.....i recabled today and tested ..im assuming the excessive use on halogen has caused the rapid deteriation in my wiring?? opinions please....

 

[Amp David]

Cant see why your wiring has aged so quick, its a new one on me.

Never had a problem like this on before on any jobs i've done. Are they sure it was the RCD that was tripping and not the MCB?

 

[zedess]

Yeah it was the rcd, as it has a rcd as a main switch so it was knocking the lot off!! could understand a loose connection maybe on one lamp but half the wiring was bloody perished!!

 

[giggsy]

Could it down to the proximity of the cables to the downlights? The heat they give off soon cooks pvc cable

 

[zedess]

well i give them plenty room to breathe today..cleared all insulation away...im assuming maybe the cables have either been to close to lamps or smothered in insulation not been able to dissipate the heat...with been on all day!!!..sound reasonable?

 

[giggsy]

Id say so yeah. Ive bin to a few jobs while on my apprenticeship where the previous electrician ran cables through insulation and in close proximty to the downlights and the cables were properly baked. You could snap them theyd got that brittle. Best thing to do is what youve done, remove insulation from around the lights and if cables need to be near insulation run them on top of it.

 

[Amp David]

Keep yer cables clipped to the timbers in the loft until you have to come accross to the light fitting.

One issue I have with using the dichroric types lamps, they kick all the heat out the back. Can't wait until all we have are LED lamp, no worries over heat build up and the like anymore.

 

[nickblake]

im assuming it was wired in twin and earth ,i always use fire rated units and heat forward lamps , and leave the customer a box so they know the type of lamp to use also i always wire to a JB in twin and earth then to the down light in 85/95 Degree HR cable

 

[zedess]

thanx for yr opinions input lads.

 

[Amp David]

im assuming it was wired in twin and earth ,i always use fire rated units and heat forward lamps , and leave the customer a box so they know the type of lamp to use also i always wire to a JB in twin and earth then to the down light in 85/95 Degree HR cable

Same here.