If this is industrial and looks are not a problem an armored door cord is your best and most cost effective option, Securitron makes a nice one and not too expensive. For running the cable you usually can not run thru the middle of the door without some drilling, your best bet is to go up and over, there should not be a top to the piece running on the top so you can just run right across and drop down into the two sides. If looks are important than the only way to go is a transfer hinge. I just finished up a job for Polo Ralph Lauren at their main building in Manhatten and I put in a bunch of them going to electrified leversets. If you do use a hinge good luck stripping the wire, I think it is 26 ga stranded.
