24 volts sytem with 12 volts headlights

hi guys

I am still working on my old Bertram . I finally have a nice 24 voltsDC battery bank and i want to go with all the cabin lighting now. The issue I am facing is that all the led lights I found are 12 volts DC.
what kind of converter do I need to get .Or is there another way to do this without burning all my lights,

thanks
Gabe

 

Search on Ebay for DC-DC converters. Chinese suppliers offer these for only 2 US$, postage included. The output voltage is adjustable 3.5-15V, max load 2 amps.

 

You can also wire lights in parallel pairs.

 

If you look, you can find MR16 LED bulbs that accept 12V or 24V. I believe that is because typical LEDs use a switching current regulator inside the bulb.

 

... or series pairs, in this case.


This may not work with leds, depends on the electronics in the bulb.

 

Oops

 

Most led worklights I see are 12-30V for reasons mentioned above

 

Look into a series parallel switch.

 

You will shorten the life of many 12v led if the voltage goes higher, low voltage is better but the light will be dimmer.
I would use the power supply in the attached file. But if you go for the cheap Chinese converters, make sure they have EMI filter.
When I use led strip on 12v I connect 2 or 3 diodes in series with the strip to lower the voltage.

Axel

 

that is true for individual bulbs but actual headlight units and work lights already have a current control in them - thus they work exactly the same at 12 or 24 volts.

 

Many cheap LEDs that work perfectly fine for interior lighting etc will NOT work on both 12V and 24V. Most are not regulated other than with resistors and will burn out. Just make sure you get the right ones, or run 2 x 12v ones in series. Or buy a cheap DC/DC convertor which also cost almost nothing on ebay.

 

I'm not so sure the series connection would work. An LED light consists of a bunch of LEDs and a current regulator connected in series. The LEDs drop some of the voltage and the excess voltage is absorbed by the regulator. Connect two such devices in series and the excess voltage will be absorbed by the regulator that runs at the lowest current, potentially causing it to overheat and fail.

 

Current is the same in all parts of a series circuit. Thats an electrical law. So both LEDs in series will be running at the same current.

Calling a resistor in series with an LED a regulator is a bit of a stretch. This is the cheap type I am saying will work fine in series. The ones with a real regulator will often be specified to work over a range of voltages. I'm not sure if you would want or even need to connect this type in series.

 

The converter is still the safest bet but if you want to determine which type you have wire a resistor in series and note if intensity changes. A resistor is more likely in low-power, cheap devices, higher power types intended for battery power may use a chopper-style regulator for maximum efficiency similar to modern trolling motors. No way to predict how choppers will react to being wired in series.

Also check the the installation instructions . . .

 

From an energy use standpoint, avoid bulbs/LEDs or systems that use resistors and use bulbs that include a switching current regulator.