I'd be careful with electrical stuff on the floor. If you spill some water, trip over it, whatever, it's going to cause trouble. As someone who has messed with plants indoors for over a decade, I can safely say it's going to happen regardless. It's your choice if that accident is going to kill you, the tree, or kill nothing at all.
Mount it high and dry.
I once forgot to turn off the power when mounting a light, and the shortcircuit (is that a valid word?) burned a hole through my expensive reflective panel. Now that was just stupidity on my side, guilty as charged. But more than once have I tripped over wires by accident and tore down the lighting setup with it. The plants weren't happy, I wasn't happy. Cable ties, they exist for a reason ;-)