jwnmkm's electrician "didn't remember how he wired it". I have the same problem. A transformer has malfunctioned, but following wiring visually from switch to where it "disappears" behind base cabinet, we can't tell where transformer is. There is a granite slab backsplash between base and wall cabinet. Without disassembling entire kitchen, is there a way to find out where transformer is or how far from switch? I remember decade ago a tool we used when wiring commercial properties to determine where a break would be, but can't remember what it was called. Thanks for any help.

The basic layout should be 1) Your switch should be fed from the branch circuit. 2) The transformer should be in a junction box that is accessible - eg not behind a finished wall. The transformer will break eventually. 3) The power should run from the switch to the transformer on a continuous wire. 4) The wire between the transformer and the first light should be continuous. 5) The wire between the first light and the second light should be continuous. Any wire that you use before the transformer should be of the same gauge as the wire coming to the switch. Any wire after the transformer needs to be of at least comparable gauge to the wires that came in your kit, just longer. If that means you have to buy some additional wire for any of those runs, so be it. Even if the chance starting a fire with a low voltage wire is small, it still isn't something you want to splice and then hide inside a wall or ceiling. Treating 12V like normal voltage might seem like overkill, but you can easily start a fire with a 9V battery and some steel wool. Low voltage means that it won't kill you if you touch the wire. It doesn't mean that it can't create heat or a spark. If you are burying low voltage lights for landscaping, you don't really need to worry about catching the ground on fire. If you are going to put low voltage wires in your walls or ceiling or anything else that could burn, then you should take the same safety precautions that you would with any other wiring.

it takes a circuitous path that requires about 12' of cable. That's fine. They want a minimum 10' of cable between the transformer and first fixture.

Thanks davidr. Below is the wire I'll be using - the description says 10/2 stranded, so I should be ok. I'm actually a little dubious over their 10/2 claim as in person it looks like regular lamp/zip wire, but I'll go by their spec. It was the guy at the lighting store that said magnetic transformers are not affected by longer cable runs. Or maybe he meant that I'd need a larger transformer and those are only available in the magnetic type. Anyway, thanks for clearing it up for me. Here is a link that might be useful: Ambiance low voltage cable