Using regular 14 Gauge Romex for low voltage wiring projects

The title of my message is actually the question I have. Want to replace undercabinet 110V lighting with low voltage Xenon hardwired lighting. To save myself some ugly wiring scenarios I would like to use the already existing wiring and switch to controle the light, of course with the use of a transformer. Anyone's thoughts on this are welcome. If it can't be done, please give me some explanation why not. Thank you

 

If the amperage is 15 amps or less, you can use 14-gauge Romex for low voltage. Just make sure that this wiring does not share the same electrical boxes with any 120-volt lines. And I would clearly label it as low voltage, perhaps with a sharpie on the back side of the wall plates.

 

Your voltage drop on the low voltage side of the transformer can rise quickly using the #14. The LV systems I install use #10 to avoid this.

 

Thanks for your replies. Much appreciated. Both your answers made me decide not to pursue this project. In the first place, the switch I want to use is in a 3 Gang box shared with 110V wiring. It's a 15Amp circuit.
And the other suggestion to use #10 would defeat the purpose, because than I still would have to run the wiring from the transformer to the destination which I was trying to avoid.
Mixing low voltage with grid voltage like that is against the code I guess.

 

I don't know if you are having as many power failures as we are here in ontario ... next to a NANTICOKE COAL FIRED future NUCLEAR Power PLANT ... but at Canadian Tire .... they were clearing out 12 volt to 120 volt AC; 300 watt inverters for 10 bucks. With a bit of tinkering a few relays, now my low power stuff, usually at nights, ... bedroom lights, tv, clock radio are now wired to 120 volts from the township, but when the power goes out, the same hydro lines in the house, all 14 gauge, sends a 12 volt dc driven 120 volt ac backup supply thru the house. A good tractor battery, "deep cycle", 1000 amp cranking current , will run my house for about 12 hours, and is trickle charged till its needed again, which is very rare for the hydro to be out that long except in the summer of 2003 when we lost all power for 3 days ... then thank GOD for CANDLES and alcohol stove heating cans to cook in !!!