Converting 120v wiring to low voltage

You could do convert your wiring, and I think when the market and the NEC catches up, that will be the way to go. But right now, it seems like the way to go is using an LED fixture, which runs off 120V and does the conversion within the fixture,

Random LED flood light fixture

or LED bulbs, which to the high to low conversion within the bulb,

Big box store's outdoor led floods page

To me the easyest way is to keep your 120V sensor and install outdoor fixtures with the LED lamp that has the electronics in it. If you go low voltage then you you will have to add a weather proof box for the powersupply that is powered from the sensor then a fixture and LED. your power bill will be lower in both cases and many of the LED's have life spans of 10K-20K hours burn time. temp really dosent bother them I mention this as CFL wont start below 20 deg F and they burn up trying. some times just get close to freezing and they have a hard time, I converted 2 elderly clients over to LED several years ago that I used to change thier driveway lights almost yearly, I think out of 50 I have had to replace 3 (1 got run over LOL) and they are instant on at full brightness not minutes like metal halide or CFL

No sense converting to low voltage, just wasting money.

Instead just use LED outdoor rated bulbs. But a few things to consider...

• Assuming the sockets are not damaged and the sensors are rated for LED, the quick fix would be to replace the flood lights with outdoor rated PAR38 reflector LEDs.

• If you don't know if the sensors support LEDs and/or if the sockets are good then you might consider just replacing both flood light kits, sensors and all and using the above mentioned bulbs.