Hi David Petersen,
WELCOME! to the forum.!
Hang in there for more suggestions and much success to you with your CPAP therapy.
05-15-2015, 11:09 AM
(This post was last modified: 05-15-2015, 11:13 AM by dhawker.)
I have a Resmed S9 that I take on my motorcycle for multi week camping with no outside electricity and have no issues. Here is what I do. First I have a second motorcycle battery (AGM type) dedicated to power the CPAP machine that charges off the motorcycle while driving. I don't take the humidifier as it requires a lot of power to run. The key here is to use a VSR (voltage Sensitive Relay) that you can purchase at any marine store, to control when the charging takes place. The VSR will not start charging the the second battery (CPAP) until the main battery voltage reaches 13.2 volts approx. This stops the CPAP's discharged battery from sucking juice from the main motorcycle battery when the vehicle is stopped or parked for instance. If too many voltage sucking things are running, like heated grips, vests, driving lights, etc. and the voltage is below 13.2, it won't charge the second battery. I use a volt meter on my bike to determine actual voltage level while driving. The next item you need is the 12volt power adapter designed for you CPAP machine (Resmed has one for the S9). I keep all the CPAP electronics together in an old tank bag and just plug it into the bike via an SAE connector (Battery Tender) and then unplug to take to my tent at night. I have camped many nights in a row with no problems whatsoever keeping my CPAP running. I also usually charge up my cellphone and other electronics off the battery in the tent as well as run the CPAP machine. Hope this helps you in your quest to get a great nights sleep.
I have the Z1 auto, the size is the value to me. Motorcycle trips are always a struggle with space and the Z1 fits pretty easy. I don't have the battery pack but HDM offers a 12v cigarette lighter plug that should charge battery during your ride time. I would call HDM and ask what the wattage draw is for charging the cpap battery. From experience some bikes don't have much extra headroom in the electrical system. As far as the Z1 Auto performance, it's hard to compare to your regular cpap, it is louder. The sound it makes is different, I can say it loud but noticeable.
Being a bit of a bike mchanic asking a bikes charging system to charge one. Battery from dead and maintain another at the same time is asking to be stranded with a fried voltage regulator or stator.
Probably get by with it for a while but even with a switch its still a tall order.
Older Gildwings, 1200 models ie early to mid eightys can be converted to a car alternator and have tons of reserve charging capacity.
Newer models and bikes that arent horizontal cylinder layout dont lend themselves to that though.
Converting every light on the bike that can be to LEDs will gain some reserve charging capacity.
I travel on a little Yamaha XT250 motorcycle. At home I use a Resmed s9 but carry an old cheap Resperonics machine on the bike since it gets beaten up on the dirt roads.
I've been powering it with a lithium power pack which works for several nights, no humidifier. But but it has no internal charging regulator so it has to be charged with its ac charger via a small inverter. Ridiculously bulky, convoluted and cumbersome but it works so far. Reading the posts here, there are better ways.
My other concern is frying either the regulator or stator over time from charging one while maintaining another, as mentioned.
I recently replaced the bikes battery with a lithium which has its own charging controller. If I got another one of those, I could use a switch so that the bike would only charge one of them. In the morning I would plug in the second battery (depleted), start the bike on the first battery, and switch to the second one. Seems like this would do the job and protect the bikes electrical sustenance from an overload.
Going to add a product that I just found as well. Suaoki Portable Solar Generator, Amazon info B018GE8JPY I'm looking for others opinions, I have emailed questions to the mfr, and will post responses if I receive any.