What device can I purchase to monitor my electrics long-term?
lots of different ways to monitor &amp; record voltage, plugin board or usb for your computer sounds like the cheapest way to go to me they are cheezy but work ok to take the measurements you describe, I would tell your land loard he needs to have an electrician tighten the wires in your pannel the humming is a really bad thing and can be the start of arcing that can distroy the ends of the wires and terminals of the breakers, that sounds like where most of the problem may be from your description. here is a very inexpensive unit and there are lots of other options out there. http://www.dataq.com/resources/images/products/starterkits/di145-usb-data-acquisition.jpg