Amps / volts / watts and 12v (14.4v?) led lamps?

[carbon]

The only way to reliably tell what the current draw is is to use a ammeter to measure the actual value. Using the wattage value supplied is unlikely to be accurate, but if you use those values then your wiring and relay will be unlikely to fail.

 

[sako243]

but if you use those values then your wiring and relay will be unlikely to fail.

No because your fuse should be sized to protect the wire not the item on the end (or could be a smaller fuse value).

Oops misread unlikely as likely

 

[julianf]

So, the lamps have turned up - amazingly quickly.

I hooked one up to a battery at rest. The battery voltage was 12.3 volts.

Draw was 1.4 amps.

That gives about 17 watts.


Significantly less than the 144w quoted!


Ill try them at 14.4v later, but it seems i wont need anywhere near the thickness of wire expected!

 

[carbon]

Significantly less than the 144w quoted!

I would imagine that figure is some sort of equivalent light output from an older style halogen lamp rather than the actual wattage. I have some higher spec led lamps and the company that produces them uses the actual wattage of the lamp rather than some equivalent power, so a lot easier to determine the size of wire and relays to use

 

[Morris]

It is purely and simply a meaningless yank import. It may be petty, but it really irritates me. The CED is not an authoritative real English record, it is a reference to 'common (although incorrect) usage' like "train station" and "less than ten items".

The English language is compromised of imported words, French, Latin, Germanic, Old English, Scandinavian, Indian plus others, all acquired and incorporated over the centuries. To claim there is some sort of static everlasting reference is ignoring the nature of language. It changes with time and generations.
American English still uses words and phrases that went with the first colonists.

 

[Red'n'Black]

I would imagine that figure is some sort of equivalent light output from an older style halogen lamp rather than the actual wattage. I have some higher spec led lamps and the company that produces them uses the actual wattage of the lamp rather than some equivalent power, so a lot easier to determine the size of wire and relays to use

Yep. They often quote an 'equivalent watts' figure but it's not based on any measurements, they just multiply the actual LED power by some fudge factor, anywhere between x5 and x10.

I try to buy lamps that quote a lumen figure, then you can at least compare like with like.