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LEDS and their associated controller circuits will be damaged by voltage spikes in a much shorter time than the comparatively robust incandescent bulbs. Which still can be blown by a surge, but not by the short spikes that will kill electronics.
 

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poker, it is onl complicated if you want to "do it once and do it right".

A white LED typically needs 3.6VDC to operate and one way to match that up to 12 volts is by daisychaining four of them to one power connection. 4x3.6=14.4 volts which is conveniently "alternator voltage" will power a chain of four white LEDs pretty nicely. Of course then the engine is off they'll dim and that'a waste. Or you use chain of three (3*3.6v=10.8V) and they'll work fine of a dead battery but tend to burn out if the engine is running....

Maybe Ikea uses those robust wild-free-range Scandanavian LEDs that match up better, or maybe they use something to control the current, which solves the problem much better. Kinda like changing the coffee filter once in a while,and only re-using the grounds twice. You may notice a difference in the quality of the coffee when you do that. :)

If the LED comes with specs, you can run the numbers, there are plenty of web sites that tell you how to match voltages or power. No specs? You generalize by the color, and if it only lasts five years instead of ten, most folks aren't going to complain.
 

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As semiconductor devices, LEDs will be more sensitive to reverse voltage and overvoltage than some of the other lights, so I'd expect them to be more easily damaged by lightning strikes. Just like all the other electronics on a boat.

But having said that, I'd still use LEDs because a good lightning strike can also blow out every kind of light and appliance known to man, and they routinely do that even in homes. You could probably take steps to harden the lighting wiring so it was less likely to get an inductive surge from a strike, or less likely to carry a strike, but lightning is such a damn pigheaded creature, that you could probably spend less by just changing the blown LEDs. Along with everything else the lightning struck.
 

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"How often do you expect lightning strikes ...Personally, I carry spare everythings aboard anyway. "

Light bulbs are electrical devices, they're fairly robust. LEDs are electronic components, easily destroyed by a plain static discharge of only single-digit voltage or static.

Light bulbs cost 79c each. Okay, $3.49 in the inflated chandleries but still under a buck apiece if you know where to buy them. LEDs, which often cannot be replaced except as a larger electronics board or module, or an entire sealed fixture? Could easily be a $50-150 "spare" to keep on hand.

Good luck carrying the spares for LED lights, you may find they are way more expensive than you think. One of the reasons why some folks haven't converted to sensitive and expensive LEDs.
 

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I'm aware of all the pros and cons of LEDs, I was just limiting my response to what was said in one post. Carrying spares, and the cost of spares, is entirely separate from any question of power budgets and capacities. 100,000 hour life expectancy (for properly engineered devices) and potentially 20 fewer trips aloft to change a light bulb, or twenty nights not spent in the dark waiting for daylight to change it (G) all are separate considerations from the sheer cost of carrying spares for these fixtures.
Considering the way LEDs and their prices keep improving? No spares, gamble on needing a new one in five or ten years. All other considerations aside.
 

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"We have 60 cabin LED bulbs and 13 LED lights aloft. Even with all on at once, 0.4 amps."

That would be 73 LEDs drawing a total under 400mA. Making them less than 6mA each.

More likely, 2-3 amps in total, no? LEDs drawing 6mA simply aren't bright enough to be used for much on a boat.
 

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"LEDs used to fade out from over heating."
That hasn't changed, they still can and do. Typical numbers are sometimes listed 100,000 hours of life, brightness down to 50% at 50,000 hours. Others just say 20,000 hours. They all fade as they age and improper heat sinking or excess power supply cause them all to age prematurely.
As with tungsten bulbs, the prime LEDs outperform the no-name generics in pretty much every way. And cost more.
 

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"Drivers are tiny voltage spike protectors."
Nope. They could have a spike protector in them, although I've never heard of that. An LED "driver" module converts raw power from whatever source into tightly regulated DC power for the LED. It regulates both amperage and voltage to prevent damage to the LED from either. A conventional 3-pin regulator set up in amperage regulation mode usually will suffice.
Spike protection can be done easily by inexpensive components like zener diodes added to the power lines on a system basis, not necessarily per LED.

"LEDs are no where near as bad as those 40 dollar 1157 substitute jobs "
Many of the 1157 substitutes include a regulator and literally dozens of LED chips carefully mounted in a small assembly intended to provide even 360-degree illumination. Some include reverse polarity protection as well. They're very different from one or two raw LEDs and while they're expensive, you'd be hard pressed to make the same thing for a lower cost.

They're not just shiny lights.

High brightness "white" LEDs, from prime vendors and one production batch, typically can range 16-fold in brightness, and you pay dearly if you want them all from the same batch (i.e. 10cp, 20cp, 40cp) instead of the random run of varying brightness and colors. Typically, vendors sort and sell at least nine different batches, all very visibly different, from any production run. Other colors may be more uniform, but on the brightest LEDs, they still come in very different brightnesses.

Sometimes cheap stuff from China is all you need, like truck and bus marker lights where a $300 light would be stolen off the back of the bus, while a $25 light that burns out half the LEDs is still "legal enough" and can be replaced at the annual depot maintenance anyhow.

Cabin lights? Cheap enough and easy enough to replace every year. masthead lights aloft? Yeah, you might want the better ones that will last 100,000 hours and still pass muster. With proper regulation and drivers and voltage spike protection, and that won't create an RFI problem, either.
 
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