Changing solar powered lights to mains powered

[jonnyl888]

Hi, we have 6 solar powered lanterns outside our restaurant but the problem is that they are very very dim and do not last very long.

This is how they work:
- Solar panels on the top charge 2 AA 1.2v rechargeable batteries.
- When it detects night, the power from the batteries is directed to the LED light in the lantern turning them on.
- They last about 2 hours max before they become dim.

Is it possible to replace the power source (2x AA rechargeable batteries) with a transformer connected to the mains outputting 2.4v? Then just linking up each lantern in parallel? Also the lights are outdoors, is it safe to do this because it is a very low voltage?

Thanks.

 

[MikeMl]

As long as the transformer is mounted in a dry location (indoors?) then running a low-voltage pair (like the outdoor Malibu lighting zip-cord) will work fine. You might have trouble finding a 2.4Vdc Wall-Wart (plug-in power supply) 4.5V to 6V ones are more plentiful. Changing the resistor in-series with the LED inside the lantern would make it so that you can operate the lanterns on any available DC Wall-Wart.

 

[jonnyl888]

If the LED runs on 2.4v of DC battery. Do you think it would be ok to run 6 LEDs on a 3v DC transformer without any resistors?

 

[MikeMl]

If the LED runs on 2.4v of DC battery. Do you think it would be ok to run 6 LEDs on a 3v DC transformer without any resistors?

You NEVER,EVER run LEDs without resistors in-series. Running the original lanterns on 3V instead of 2.4V depends on the how the current limiting was accomplished in the original circuit, and what the forward voltage drop of the existing LEDs is.

 

[Nigel Goodwin]

I would suggest you put some proper lighting in place, those LED lights are pretty useless at the best of times.

 

[jonnyl888]

The lights aren't there to light up the path but more to direct people through the path at night. I think there's a 47 ohm resistor connected to the LED in series already. So what I'm going to do is put the 3v DC transformer in the place of the AA batteries. Hopefully nothing will blow up.

 

[jonnyl888]

Because I'm working with such low voltages can I use a bell wire to connect up the lights?

 

[Noggin]

You NEVER,EVER run LEDs without resistors in-series. Running the original lanterns on 3V instead of 2.4V depends on the how the current limiting was accomplished in the original circuit, and what the forward voltage drop of the existing LEDs is.

You can if you use a current source.

 

[MikeMl]

You can if you use a current source.

A resistor is nothing more than a lousy current source. I guess I should have said: You NEVER,EVER run LEDs without a current-limiting device in-series.