I just use a regular car type or deep cycle battery, no humidification, goes for a very long time. Either run a cheap harbor freight inverter, or just run it as 12 volt, as most cpaps are.then charge with normal gen during the day.I am looking for an inverter generator to power my CPAP while I'm in hunting camp for 12 days. Will trade what I have advertised in these forums for one. You can see the exact details of what I have for sale by looking at my posts in Buy and Sell, but a quick recap of what I would trade is this:
Ice fishing gear (3 rod/reel combos, jigs, accessories) asking $130
Parkerized British .303 with scope mount + 80 rounds ammo asking $325
Redington Crosswater 5 wt 4-pc 9 foot fly rod and reel combo with case. Comes with Umpqua medium fly box and 92 flies + many accessories asking $225
So, if you're interested in trading, let me know what you have for an inverter generator.
Which machine you got? You don't need an inverter generator, unless you have to have humidification, and even then you don't.