Thinking about small generator for backup

[archangle]

Resmed machines may need inverters for 500 watts:

That page is horribly poorly worded.

S8 CPAP blower unit only, 150W MSW (Modified Sine Wave) is OK.
S9 plus humidifier, 150W MSW is OK.
S8 Humidifiers, 300W continuous, 500W Peak, PURE Sine wave is needed.
When it says "Humidaire must not be used with inverter," it means the really old models, not the ones labeled with HumidAire "C series, 2i, 3i, H4i, or H5i."

Thanks for the page from that doc avi. The original is here: http://www.resmed.com/us/assets/documen ... lo_eng.pdf

[DagoRed]

I was wrong as to the brand, its a DieHard 400watt. I bought this st the local napa autoparts store 4-5 years ago, they are like 50.00.
Here is a pic.

[avi123]

Because the title of this thread is about a generator, further discussion about batteries was moved to here:

viewtopic.php?f=1&t=83669&p=758941#p758941

[Lane Scott]

For my GoodKnight 420G (12V DC) I use an 18 Amphour sealed lead acid battery for back up and camping. I've built the backup unit myself with standard connectors and cables form an electonics supply store.

The CPAP draws just under one amp per hour and I easily run the unit for two nights while camping. I also have a ProBasics Zzz Pap that runs at 120V AC and use an inverter with that to achieve the same result. Note that for the Zzz Pap I don't use the humidifier while on battery as that would draw too much power. If you need the humidifier an upgrade to a 35 amphour battery would likely do the trick and give you two nights for a unit with a similar draw to the Zzz Pap.

Another advantage of the inverter is that you can attach it to your vehicle to recharge you CPAP batteries (via a charger) for an extended power outage. In my case I've a small 800 watt generator for basic lighting and charging of electronics for an extended outage (realize it won't run heavy duty items like a refridgerator) - don't want to store the fuel for a larger generator.

Hope this helps.

Regards

[Journeyman]

Well this reply is about an inverter type generator. I have a Yamaha EF30iSEB. This is the 3000 watt model. It runs on gasoline, propane, or natural gas. At 1/4 load 5.82 amps it will run about 20 hours on a 20 pound BBQ type propane tank. This will run my furnace Propane stores very well. Check out ---- "US Carburetion Inc". Google them, they are a Tri fuel generator Yamaha dealer. They are great people to do business with. I believe the 2000 watt model will ship UPS. Its all on their site. They are in Summersville, West Virginia. I would recommend them to anyone. I have used My cpap machine while at deer camp running on a "2000 watt yamaha Tri fuel inverter" while on propane for a week. No problems at all. The 2000 watt ran my machine, a camper refrigerator and several lights. They are very quiet running units as well.
On EDIT; There were two cpaps running at night, mine and another guys in another trailer. Also a ten inch fan on low, with the outside lights and camper refrigerator. The 2000 watt model will run @ 13.3 amp draw all day long. It will handle a surge to 16.7 amps. Its a very nice unit. I saved my money for about four years trying to decide on what to buy. I wanted mine for the furnace in the house, didn't know about cpap four years ago. The 2000 watt unit weighs about 50 lbs. Its not very big, smaller than a 40 quart cooler. The 3000 watt unit weighs a little over 150 pounds. It will run @ 23.3 amp draw all day long. It will handle a surge to about 30 amps. It comes with wheels and with a little ramp it will roll or fit into most any camping trailer.

[archangle]

The CPAP draws just under one amp per hour

That would be "one amp." "one amp per hour" is the wrong units.