Cpap, Inverter followup

[brenkco]

Well, our first weekend boondocking. Here is what I have learned about the cpap. I acutally have a bipap with humidifier.
I first tried a 140 watt, single outlet inverter plugged into 12v TV outlet (Carl & HamRad's suggestion). Worked fine without humidifier. Humidifier overloaded inverter and shut down.

Second, I tried a 420 watt, double outlet inverter w/ digital display. 12v outlet cord stated do not exceed 100w using this cord. Tried machine without extension cord, humidifier on. I was drawing about 96-103 watts and seemed to run ok. Tried using a 16-3 extension cord to reach the headboard and the inverter over loaded and shut off. Other problem was the inverter was very loud.

I also purchased a 740 watt inverter but didn't bother as the 12v outlet cord had the same 100 watt warning.

I imagine both of the larger inverters might have worked using the direct battery connection but I opted to use the smaller, quiet inverter without the humidifier.

Bottom line is the small, cheap inverter as suggested was the best solution for a few days of boondocking.

I still plan on ordering the 12v cord for the bipap machine itself. The one spec I have found says the the machine draws 5.0a, 12vdc with humidifier.

Thank you to all for your help.

Ken