what amp rated cable should i use for spotlights

[Hugh Jardon]

a question for you leckies out there, what amp cable should i use to run a pair of spotlights that are 55w or 100w at a distance of 6-7m from the switch and relay assembly. I cant seem to find any info easily that tells me this. gauge of wire or amp rating would be fine, i would probably just go with twin 55w lamps but would be interested in cable sizing for 2x100w lamps

[Mollers]

Stroll on!! Talk about boat building by numbers! Didn't you get any instructions with it?

[Hugh Jardon]

i am prewiring the boat for additional items i will add in the near future or items a future owne could add, so that it is just a case of connect and go so to speak, flood wiring it could be referred to as i suppose!!

Originally Posted by Mollulnan

Stroll on!! Talk about boat building by numbers! Didn't you get any instructions with it?

[Mark Halliday]

28/0.03 2mm² is the smallest you want.

Standard cable rated @ 17.5A
Thinwall cable rated @ 25A

Why?

P=iV

i = 200W / 12v = 16.666.....A

[Edit]
Have a look at www.vehicle-wiring-products.co.uk/VWPweb2000/homepage/home.html for some useful info.

[Hugh Jardon]

thanks for the link to the site, very useful, it was the voltage drop i was interested in over a 7m length but i have been advised it should be minimal so will order up some cables today

thanks

Originally Posted by Mark Halliday

28/0.03 2mm² is the smallest you want.

Standard cable rated @ 17.5A
Thinwall cable rated @ 25A

Why?

P=iV

i = 200W / 12v = 16.666.....A

[Edit]
Have a look at www.vehicle-wiring-products.co.uk/VWPweb2000/homepage/home.html for some useful info.

[Mark Halliday]

There wont be much voltage drop over that length.

Again by the above formula, yer 200W will be little less, thats all.
You will still have enough to dazzle your hardboating chum.

[Scary Des]

I’d be inclined to use marine grade wire it does help to stop the rot having said that tis more expensive so it might be worth doing a cost benefit analysis Des

[UKPOWERBOAT]

Originally Posted by Mark Halliday

You will still have enough to dazzle your hardboating chum.

Oooohh B**ch

[Hugh Jardon]

i am fitting a rear view mirror especially so i can keep and eye on him....haha

Originally Posted by Mark Halliday

You will still have enough to dazzle your hardboating chum.

[Mark Halliday]

Originally Posted by Scary Des

I’d be inclined to use marine grade wire it does help to stop the rot having said that tis more expensive so it might be worth doing a cost benefit analysis Des

A dab of "Liquid Tape" can stop the nasty salty air getting down inside joint and the insulation.

Originally Posted by Nauti Buoy

Oooohh B**ch

Originally Posted by Hugh Jardon

i am fitting a rear view mirror especially so i can keep and eye on him....haha