LED Lighting System

LEDs are so long lasting and dependable, I would consider wiring four units in series. Sure, if one fails they all go out, but it would be easy enough to find the bad one. Just keep spares, like a Christmas tree bulb set.

http://www.axiomatic.com/48dc-converter.html
https://www.powerstream.com/dcdc.htm

A simple, and cheap solution that I have used is to use a back biased zenier diode to take up the excess voltage. In this case, three 12 volt zenier diodes in series will do it.

Take note however, you must consider the current that your system uses and make sure the diodes can take it.

Simple, easy, and inexpensive!

I'd have to vote for the series of 4 myself. The zener solution would work, but you would be wasting power in the zeners, and when you are talking battery power, you want to minimize the heat losses as much as possible.

My .02 cents worth.

Tom D.

I wouldn't use a 4th zenier because then you would have to have some current limiting device. I'm saying to dissipate the 36 volts across 3 zeniers and let the lighting system be the current limiting device with the remaining 12 volts.

If you're interested in saving a few watts, a DC to DC converter is the way to go. I'm sure we could calculate a return on investment if we had some more information.

Using zeniers to waste heat is much easier than trying to use resistors and regulators. It all comes down to pay now or pay later.

X3 power will be consumed in Zener.

Why not get a converter [voltage] from 48V to 12V?

I'm not a boat guru, but my guess it that your boat's 48v system comes from (4) 12v in series. Is the solution as simple as just running new wires to one of them?

What we really need is for Moomoo to get back in here and provide some feedback!

Tom D.

In my view the simplest solution so far.

thanks chaotic, but all the 4x12v batteries are sealed, made in china type, where no accessability is allowed! so i guess the best is to put 4 light modules in series and make them work, involves some work in putting long wires, but i think that would work.

Battery itself is a sealed-care-free but their connections to each other are also sealed and not accessible?

I hope not. Here is the point to tap for one 12V battery for 12, 2 for 24 or3 for 36V.

Putting 4 light modules in series will only work if they all have the same amount of load at all times. If not, the voltage division will not be even so regulation is going to likely be nearly impossible.

That is why I recommended the use of 12V zenier diodes. To save some energy, you could use a combination of 4 modules in series with a 12 V zenier in parallel with each section of 12 volts. This would be a simple method of regulating the supply. Unfortunately, if the battery voltage drops to less than 48 volts, then one or more modules will suffer slightly. But without them, and using only 3 modules while one of them is off will result in 48V being split mostly among the remaining 3 modules.