12/24v LED rear lights

[Anton]

Ladaman - aren't those the same as the ones Dan got?

You might still need to change the indicator relay

I should change mine, my indicators flash a bit fast (MOT man is ok with them) and all I've done so far is put LED bulbs in my side repeaters.

Why not use something like these:

Those do look good, but I'd find out what wattage they draw first. I tried elcheapo LED bulbs in the Land Rover (ugh, what a stupid move) lights I fitted on the back, and it flashed way too fast.



I got stop/tail and indicator bulbs. They all sucked pretty damned hard. You could barely tell they were illuminated during the day!

You get what you pay for, thankfully I only wasted about a fiver on those. If I got LED lights in future, it's going to be decent ones and I'd check they were putting out a similar amount of light to the ones Dan and Ladaman fitted - which according to the specs on this page is:

0.07a @13.8v (0.966W) for stop
0.02a @13.8v (0.276W) for tail
0.19a @13.8v (2.622W) for indicators

That's not the whole story (LED efficiency, wattage output vs surface area etc) but it'll give you an idea of whether or not these LED's are any good, I think.

[Rhinoman]

0.07a @13.8v (0.966W) for stop
0.02a @13.8v (0.276W) for tail
0.19a @13.8v (2.622W) for indicators
That's not the whole story (LED efficiency, wattage output vs surface area etc) but it'll give you an idea of whether or not these LED's are any good, I think.

It doesn't mean anything at all, there are many different types of LEDs, the light output in lumens and the angle of the beam are the numbers that count. You can get a variation of 100x the light for the same current draw. If the lamps are E marked then they should be OK.

[Anton]

Right, but there's no lumens ratings on the assemblies Dan/Ladaman bought, so the only figures we have to work with for a comparison are those amperage figures. As I said, it's not the whole story, and yes, getting lumens figures would be better.

Knowing that the kit Dan/Ladaman have work well (according to those who've seen 'em) the idea was to try to get some kind of comparison going.

I mean, light output in lumens and the angle of the beams is still not the whole story, as a light can put out a higher amount of light in lumens in a similar or identical beam angle and yet still be visibly dimmer if there's simply more surface area being lit. And a tight beam could result in a brighter lamp at the same or lower lumens, but do you really want that? Do you want your tail lights to be less visible to a vehicle behind and to one side of you than directly behind you?

I get your point though, E marked lamps are probably the way forward, or at the very least only buy from someone who's willing to take back a lamp that isn't bright enough for a full refund.

[dan_2k_uk]

Somewhere I have photos of them lighting up a whole farmyard behind it red at night.

They are very bright.

[dan_2k_uk]

Truck looks so skinny in those photos without the 33s and big arches.

So long ago.

[djc]

That'spretty much what I'm aiming for Dan, found pics on build thread (p9 I recall). I'm going to get some steel and start creating - I want something robust-looking to keep the ladies in the Range Rovers off my corners

[Anton]

Initially, I thought of this to keep Landies and RR's off your corners:



But then I realised that it's overkill - this is Landies we're talking about here! This is more than enough to destroy a Landy:

[djc]

The reason I looked at the 12/24v ones was I want them quite bright, and those have a lot of LEDs in them, I suppose it isn't that simple but. I got a cheapish set for the trailer a while ago (12v, about 30 quid) and they are excellent, way brighter than my old dodgy SJ ones. I'm guessing any decent set will be a big improvement on the existing, noticed near side side was off yesterday - I never seem to have all working at the same time, think one of brake lights is out too, and it's never the bulbs.
Here's the rough idea, stacked tubes each end, split in centre to clear towbar etc, lights recessed between stacked bars. Need to look more closely at mounting and hence fabricating brackets etc.

bumper.jpg (9.63 KiB) Viewed 6328 times

[Rhinoman]

and a tight beam could result in a brighter lamp at the same or lower lumens, but do you really want that? Do you want your tail lights to be less visible to a vehicle behind and to one side of you than directly behind you?.

No and therin lies another problem, it is much more difficult to source an LED with a wide beam pattern and a high light output, particularly if it isn't a red LED. I went through this issue a while back when designing an LED display for outdoor use, it gets very complex very quickly.
On a vehicle tail light the lens should be designed to work with the LED to give the correct spread of light.

[Anton]

Douglas: I reckon that would look very cool! Where did you get the trailer lights?

Maybe you can get another set if they're good?

Rhinoman: yeah, besides being really dim, the cheap LED bulbs also had a dire light pattern. You could just about tell that an indicator was lighting up if you were directly behind the truck, but off to one side and you couldn't really tell.

E marked lamps for the win, cheap ebay bulbs for the bin.