Hi im looking for some guidance for a temporary outdoor lighting installation at a festival. I want to run 18 x 10m lengths of low voltage LED fairy lights these ones.

I have some large 12v batteries and a step up dc dc boost converter like this Can i just simply boost the 12v to 31v required by the lights and run all 18 strings of one supply? operating times will be no more than 6 hours in a 24 hour period. I was told each LED is 0.007W so with 100 leds per string i will have to run 1800 LEDS. Whats the best way to achieve powering this with 12v?

I have some basic electronic skills/soldering etc..

Many Thanks Al

  • \$\begingroup\$ What you have sounds reasonable. Alternatively, you could check and see if you can dump the DC-DC and connect 3x12V in series. (Probably not as stable in output voltage though.) \$\endgroup\$ – JimmyB Apr 13 '16 at 15:30

The way you have proposed setting it up should be fine.

The lights take a 31V input, multiple chains are set up in parallel (despite appearances) so increasing the length increases the current draw.

The total load for 1800 lights should be a bit over 1 amp. So you can get a rough idea of your running time by looking at the amp-hour figure of your battery. Don't cut it fine, batteries can be combined by connecting them in parallel.

It may be possible to run the chain on 36V using three 12V batteries in series. I would suggest testing this on a single chain, let it run for at least an hour and make sure the lights don't get too hot. However given your needs and resources the first option seems better.


Thanks all. It worked a treatenter image description here

I wonder if it would it be possible to put an inline twinkler/flasher unit between the 12v and 31v ??


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