I am doing a kitchen remodel and up to this point I have re-wired everything. The H/O wants lights installed under the cabinets to give some decadence lighting for the countertops. I have dropped down switchlegs for each section of cabinets and have them on a three way configuration.
I was wondering if any of yall run into this type of install on a reg basis? Any info would be greatly appreciated.
I will tell you what typically happens in the area I work in: The cabinet installer installs the cabinets with the lighting semi flush mounted, drills a hole in the bottom of the cabinet horizontally towards the back. Then runs the wire through the hole so that it hangs at the bottom, rear of the cabinet. It is usually too short to reach your 120 switch leg, so you may have to splice to lengthen it. Then you run the wires to an accessible point where they connect to a transformer that you are switching. Usually they are 10 watt halogen, at 12 volts. So you will probably have to do some fishing to get the low voltage wires to the transformer location.
To do it right takes buying good quality fixtures. WAC makes a pretty good line voltage halogen fixture in lengths fron 12" to 48". Also the higher end GE fluourescents are pretty good. With the WAC, I stub out some 14/2 MC cable. The fixtures come with appropriate fittings. You can jumper several fixtures together with short MC whips. The wiring space is small, but doable with #14 wire. By using MC, you get away from that gray area with exposed romex. The GE Profile fluourescents come with a small junction box to run your feed into, then the lights plug into the j box with their own special cords.
A lot of the cheap crappy undercabinet lighting is tough to install in a code compliant manner. Customers just don't understand why you can't run zip cord thru the walls and cabinets.
I agree with BigB if you go with the quality material it will generally be alot more installer frindly, I have used 6' flexable drill bits and those thin flexable glow rods, and metel coat hangers for that matter to fish my wires through the walls inside the cabnants, and a variety of other techniques to fish from one elevation to another or to get get acrss usable space like a wall mounted microwave and some time those light kits do not have the needed wire lenth, well you can allways use an old work single gang cut in box (and blank trim plate later) to splice in 14/2 to daisy chain the lights or use as a switch leg.
We've recently installed Juno low voltage xenon linear lighting for under cabinets in a couple of homes, and customers are totally satisfied with the result.
Transformers are located usually in the basement...we install a line voltage wire for the switch to the basement, and install low voltage lines from cabinets to same location. Install transformer in 8X8X6 box, and splice everything there. Switch the line side. Because of voltage drops, we've been using the 24 volt system with 10 watt bulbs.
These lights are expensive, starting at $1000 (installed) for an average kitchen.
Most common for "over-counter/under-cabinet" lighting that I've installed is fluorescent. Xenon and halogen are more commonly used on top of the cabinets (sort of a "cove" lighting effect) and under the kick of the bottom cabinet.
Fluorescent fixtures specifically made for undercab lighting are available just about everywhere, even at the big box stores. They're pretty inexpensive and virtually unseen when installed properly.
Various techniques for installation is to either install the outlet inside of the cabinet or above it, using plastic wire channel where the (factory installed) cord may be visible within the cabinet - or - run MC into the drywall where it cannot easily be seen and into a box within or above the cabinet with a blank cover.
To make less of a fingerprint on the cabinet when using the factory installed cord, cut the cord cap off of the factory installed cord and run it to the outlet through the smallest hole you can get away with in the bottom of the cabinet. Run it through the wire channel and cut it to length, then install a new (usually ungrounded) cord cap plug, giving just enough slack on the cord for easy plugging and unplugging for future service.
The fluorescent fixtures can be interconnected easily with an MC whip. The reason I favor these over the xenon or halogen strips for undercab is that they require no transformer. With overcab and kick lighting it's easier to install a transformer somewhere that it will be rarely seen.
I always steer in this http://www.junolighting.com/productguide/692.pdf direction. Feed with flex in my neighborhood, or romex in other parts of the country, has built-in romex connector. Best light quality, dual light level, low profile. I pay $50+ and $90 for 9-1/2" - 30" respectively. The side feed cord connectors allow you to cut across and reduce the quantity of your drops.
We come up off the floor 36" + 18" + 5-10" on the rough and tack up some cardboard. Then we poke our whip through at the center of the cabinet. This is for the drywallers. Then the carpenters slot the drywall down 5-10" to the proper height.