Originally Posted by bapos
. . . . The bad thing is most 120v minis only go to 12k in btus so anything more you have to go to 240v. Which would be cool to run multi evaps off one condenser but Im not upsizing my genny just to accommodate. . . .
Some gennies can be re-wired for 120/240 volts. For example, the common Onan "Emerald" line of 6 kW RV gennies have two 120-volt windings, which are normally shipped wired in parallel. A couple of minutes with a service manual and hand tools are approved
to put them in series, and you have your 120/240 volt genny. Be sure to balance your 120-volt loads on both sides of the neutral, as each hot lead will now only support up to 3 kW of 120-volt loads.
*** Disclaimer: The previous is an approved usage application. What follows is totally unapproved. ***
I don't really want to say this, because I haven't tried it, but it might be possible to get 120/240 volts from a pair of "twinnable" inverter generators. The special parallel pairing boxes for the Hondas are no more than plugging into both units to parallel the outputs for twice the 120-volt current. The inverter circuits must necessarily sense and synchronize the AC waves to be in phase. The reason for the special parallel load boxes is the insulated generator leads. They are configured so if one genny is running, and the other becomes unplugged, you don't have live male prongs waiting to bite somebody.
Anyway, my theory (and it is just that) requires that you have a 240-volt, center tapped auto-transformer, like Outback makes as an accessory for their off-grid inverters. If you connect one inverter genny on either side of the center tap, the inverters SHOULD sync 180° out-of phase for 120/240-volt series operation, in the same manner they sync in phase for parallel operation. But if anyone wants to be the guinea pig with your own generators, I did not tell you I saw it work. And I do not have any inverter gennies to try it myself, but I would if I did.
YMMV. Do not spindle, fold, or mutilate. etc, etc, etc.