Backup Power Solutions
PowerGate Auto-Switching 12-Volt Power Supply
This system is basically a 12 V setup using stuff normally targeted towards ham radio operators. it consists of:
- 35-40 AH 12 V Sealed Lead Acid (SLA) or Absorbed Glass Mat (AGM) battery ~$70
- West Mountain Super PWRgate PG40S combination smart charger (like Battery Tender) and cutover switch ~ $135
- Small 12 V power supply (I have a 12 am Astron switching power supply - SS-12) ~ $95
- Wiring and connectors - These parts primarily use Anderson PowerPole connectors - can get them premade from West Mountain or Powerwerx or make them up if handy and and have, or are willing to get, a good PowerPole crimper
- DC converter cord for CPAP
- Cigar lighter socket cord to hook up the PWRgate to the CPAP DC cord/converter (if Resmed) - I cut off the cigar lighter part of the DC cord/converter and wired it direct to a PowerPole connector.
- Appropriate fusing in the cord from the battery to the SuperPWRgate
Yes, it's pricey. But even with the humidifier on I can safely get probably three nights on it. Without heat humidifier, it can go a little over 8 nights (IIRC for the current draw studies I did on several machines) If you remember JustMongo (former big honcho on this forum and electrical engineer by trade), he referenced the system as one of the most elegant (I think that was his word) that he had come across for this kind of application.
Substitute CPAP for the radio transmitter: