Description: I fell in love with the Jansjo LED wall light and I wanted to use it in my RV. It makes the perfect bedroom reading light, and since it’s based on a light-emitting diode (LED) it’s low power and you can’t burn yourself by accidentally touching it.
Unfortunately, it doesn’t run on a standard voltage. The special power adapter is built into the cord which plugs into the wall so there’s no way to use it while camping or in a trailer. No problem.
In order to accomplish this hack you will need a Janslo lamp, a sub-miniature toggle switch ($3.00 from Radio Shack), a 1-watt LED power driver ($3.00 from Sure Electronics on eBay), and the ability to solder.
Cut the cord off the lamp and remove the little plastic screw that holds the cord in place. Unthread the power cord from the hole and clip off the white connectors, using care to leave the remaining wires as long as possible.
Drill out the hole that the cord went through using a 1/4″ twist drill. Bend the contacts on the switch to be as flat as possible, slip the switch into the hole from the inside, and epoxy it in place. When the epoxy has set, you are ready to attach the cord and wire up the switch.
Solder the wires to the switch as shown using a piece of the old lamp cord. Polarity is very important with this project. You do not want to get the leads reversed. If you look carefully at the lamp cord, you will notice that one side of it is marked with little black dashes. Connect this side to the silver wire on the lamp. Connect the other side to the switch as shown. Connect the white wire from the lamp to the other side of the switch.
You are now ready to wire up the LED driver.
Strip a 1/4″ of insulation off the wires to the lamp and attach them to the LED+ and LED- terminals on the driver board using the screw terminals. Once again, mind the polarity. The wire with the black dashes goes to the LED- terminal. The other one goes to LED+.
Attach the other side of the driver board to the 12-volt wires in your RV, being careful to observe the polarity. If you hook it up backwards, you will destroy the driver board (and possibly burn yourself).
That’s it! You now have a very bright, very efficient reading light. It uses less than 1/10th the power of a standard 12-volt light bulb (150mA vs 2000mA).
~ Rick Scherle, San Francisco, CA