# Cruising with CPAP



## dailymirror

I seem to remember that a while ago there was some discussion around using a CPAP machine afloat. My wife and I are going to charter a sailing vessel this summer, and she says "CPAP or fish food - you decide". 

So, im looking for advice and recommendations from anyone presently sailing with apnea? What kind of device are you using? Can a typical boats battery bank support a CPAP machine? Ive seen some smaller battery powered machines advertised - anyone had any experience with them?


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## Scotty C-M

My wife uses a CPAP. We have an inverter installed on our boat, and two 500 AMP batteries. We run the SPAP for several nights with no problem. Your charter company should be able to advise you on this.


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## hellosailor

"Can a typical boats battery bank support a CPAP machine? "
As Scotty said. You'll need to do your homework, and find out how much power *your* machine draws. And then confirm with the charter company that the specific boat you are looking at, has the capacity to run that, with an adequate safety margin/reserve in case the batteries aren't in perfect condition. The bigger the boat, the more likely it will have a bigger battery bank and more reserve capacity. 
You might consider something like a very portable lithium battery pack:
TracerPower.com Tracer 12V 24Ah LiFePO4 Battery Pack
Not at all cheap, and if there is air travel involved, it may need to be in your carry-on, but something like that should be able to ensure you don't have power worries.


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## travlin-easy

Most CPAP machines draw very little power. My wife uses one and it only draws about 70-watts at most, so no problem running it on our house batteries and a 3,500-watt inverter.

Gary


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## Stu Jackson

Inverters - what do people use them for? | SailboatOwners.com Forums

Look for the posts by Sumner and check his website out.

I just typed CPAP in the search bar and got tons of hits. Have you done that?


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## hellosailor

70 watts, times eight hours, that's 40-48 amp hours at twelve volts. Or, almost an entire 50% discharge cycle on a Group31 battery.

So how long _is _a piece of string, anyway?


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## travlin-easy

My house batteries consist of 4 T-105s for a total of 500 ampere hours, plus I also have a big start battery that I can add to the power supply. So, in my case, no worries. I guess if you have a small boat and running on a single battery, well, that could be a problem.

Gary


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## twoshoes

My CPAP device is capable of running on an optional Lithium-ion battery pack that will run up to 13 hours on a four-hour charge. One would probably rather die in their sleep than pay the $500 they're asking for it though, unless the insurance company can be convinced it's necessary and will pick up the tab.


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## MarkSF

Without the humidifier, my Philips uses about 7 Ah per night. You don't need an inverter, the device runs directly off 12V. I have a cord that plugs into a cigarette lighter-type outlet.

I do also have a 20 Ah battery for camping, but there is no need for it on the boat.

Power usage mainly relates to pressure. Mine is set to 13. Not sure of the units - is it mm of mercury?

Humidifiers use a lot of power, so you'll have to forego that if you normally use one.


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## MarkSF

twoshoes said:


> My CPAP device is capable of running on an optional Lithium-ion battery pack that will run up to 13 hours on a four-hour charge. One would probably rather die in their sleep than pay the $500 they're asking for it though, unless the insurance company can be convinced it's necessary and will pick up the tab.


It is an allowable expense on a flex spending account, so if you have unused balance.... My battery pack is a 20 Ah sealed lead acid type that cost $300. It is a universal one for CPAP machines.


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## freshsail

My wife and I both use Resmed machines. They sell a DC converter (about 90$) which means you don't have to use an inverter. They simply plug into a 12v receptacle. Without the humidifier they use about 5-6 amps per evening apiece. Most battery banks will easily accomodate that load. If you use an inverter you will use up to ten times that many amps.


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## MarkSF

Thats 5-6 amp hours per night, not amps. The difference is quite important.

The Resmeds seem to run on 24v, so the converter will be 12v to 24v. My Philips runs on 12v, so the adapter is just a cable.


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## hellosailor

"My battery pack is a 20 Ah sealed lead acid type that cost $300. "
Medical grade acid approved by Ken Kesey, to be sure. The 20Ah AGM battery is worth $20. $60 at the local overpriced battery franchise store. 
So they put it in a $250 bespoke case with Swarovski crystals on the logo?
Right, medical grade.


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## barnacle_bill

We are going to charter with Barefoot Yachts in the Grenadines and they said they could hook me up.


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## MarkSF

hellosailor said:


> "My battery pack is a 20 Ah sealed lead acid type that cost $300. "
> Medical grade acid approved by Ken Kesey, to be sure. The 20Ah AGM battery is worth $20. $60 at the local overpriced battery franchise store.
> So they put it in a $250 bespoke case with Swarovski crystals on the logo?
> Right, medical grade.


My only excuse is that I had $300 balance left on the medical spending card, and needed to spend it. The bag it comes in is terribly nice, btw.


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## dailymirror

No I didn't think of that! Way too easy - but thanks for the tip.


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## TakeFive

We're heading to the Grenadines in early March for advanced sailing school. My CPAP only draws about 7 watts dry (70 watts with humidifier), and runs off a 12v power brick, so it should be easy to power (under 5Ah per night). Note that others could have very different power draw due to different models of CPAP and different pressure settings.

However, I've developed a lot of experience powering CPAP off of 12v batteries, and things are sometimes a little more complicated than expected. I have had problems powering off a 12v adapter on 3 different boats (my old 25' boat with group 24 battery, my friend's boat with large, brand new 4D banks, and a charter boat) using two different model of CPAP device. In each case, it appeared that the voltage dropped too much during the initial surge of startup current to get the blower running. Once started up, it was fine, but it sometimes needed a boost by starting up the motor alternator or other unusual means to get it going. It seems that the problem does not have anything to do with the battery capacity, but instead with the long wire run from battery to outlet causing the voltage drop.

I've written elsewhere about using a jump starter on my own boat, which results in a much shorter wire run that leads to flawless operation. But that device will be very inconvenient for air travel due to large bulk and unnecessary air compressor that's built into it. So I started hunting around for an economical solution. Face it, portable batteries are not "rocket science" and so-called "medical grade" batteries are basically a scam. And the jump starter that I have been using is basically just a SLA battery with nice case (and worthless compressor) around it.

I found a workable solution inside one of my UPSs in my house. It has a 12v-12Ah SLA battery inside, which I happened to replace about a year ago (so I know it's still in good shape). It has F2 connectors on it, so I took a Battery Tender harness that I have lying around, clipped off the ring terminals, and spliced on the appropriate connectors. In testing it, it drops down to about 70% charge after one night of use, and was successfully recharged by my car's alternator by attaching a double-headed 12v pigtail for a couple hours. This simulates how I would charge from the sailboat's battery bank, although without the motor running it may take longer to charge.

So here are the components of my system - I had all of them lying around the house or on the boat:


12 Volt 12 Amp Sealed Lead Acid Battery

http://www.amazon.com/gp/product/B000NCOKZQ/

https://www.amazon.com/gp/product/B0041CDPQO/

https://www.amazon.com/gp/product/B000H92L4W/

Crimp-on F2 connectors to replace the ring terminals

Spare 7.5A fuses for both the Battery Tender harness and the double-headed pigtail

Innova 3271 plug-in volt meter for approximate SOC indicator

I'll continue to test out these items this winter. But I wanted to show that you can put together something that is perfectly workable for under $50. I've attached a picture that shows the setup.

I could search for a Lithium battery of similar capacity which would be lighter weight, but they're getting a bad reputation for air travel and according to FAA would need special permission of the airline for the needed 101-160 watt hour capacity. Plus, all it takes is one airline incident between now and my departure to change everything immediately.


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## chef2sail

Wife and I both have resperonics dream machines. On our boat no issue as we carry 720 ah and each machine uses an average of 10-12 ah per 8 hours. Start up is 5 amps. We've never had an issue with the cigarette plug. 

I do a fair amount of traveling for work and have never had an issue really or need to jury rig anything. Resperonics has good adapters for less than $50. 

We have the 12 volt adaptors for our upcoming 10 day trio to the Windwards . We also have very liteweight rechargeable 40 amp small battery packs with alligator clips to recharge if necessary. These give us 2-3 days on a charge. 

We asked the charter company to provide us with an extra sealed battery to take on our charter to put in our stateroom. This way we don't have to lug a battery through customs or through the airport. Evidently it's a common request


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## pdqaltair

We just run it off the inverter. The humidifier is not needed sailing since the air is usually humid enough.

Yes, there is a draw. Economize somewhere else if you need to. Turn lights off if your are not in a room. Go to bed at night and get up at dawn; I never understood sleeping in anyway. A waste of a nice morning. Priorities.


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## TakeFive

pdqaltair said:


> We just run it off the inverter. The humidifier is not needed sailing since the air is usually humid enough...


I was told that the charter boat for our cruise and learn is unlikely to have an inverter. And we don't know whether our cabin will even have a 12v outlet. Hence, I need to come prepared.

None of this is jury rigged. The battery and all cables are being used for exactly what they were designed to do, and everything is properly fused. If crimping a couple of terminals is jury rigging, then the whole boat is jury rigged.

I've had my CPAP fail to start over weekend cruises, and I suffered through it. A whole week without a working CPAP would keep my wife and others awake, and my impaired mental state would be a safety hazard for all aboard. So I want a solution that I can pre-test at home and bring with me 100% certain that it will work. If there's a 12v outlet or inverter, that's great. I'll have my battery as a backup in case the supplied power source has problems starting up my device.

The whole thing weighs in at 9.5 lb, and costs under $50. My cost is $0 because it happened to use components that I already had lying around. I'm describing it here for others to copy if they choose. I think it is particularly useful for chartering or camping, where the type and quality of power sources is questionable. If you have something you like better, that's great! If you can suggest something that is guaranteed to work better in my situation, I'm open to hearing about it. I have 2+ months to test it out.


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## chef2sail

TakeFive said:


> I was told that the charter boat for our cruise and learn is unlikely to have an inverter. And we don't know whether our cabin will even have a 12v outlet. Hence, I need to come prepared.
> 
> None of this is jury rigged. The battery and all cables are being used for exactly what they were designed to do, and everything is properly fused. If crimping a couple of terminals is jury rigging, then the whole boat is jury rigged.
> 
> I've had my CPAP fail to start over weekend cruises, and I suffered through it. A whole week without a working CPAP would keep my wife and others awake, and my impaired mental state would be a safety hazard for all aboard. So I want a solution that I can pre-test at home and bring with me 100% certain that it will work. If there's a 12v outlet or inverter, that's great. I'll have my battery as a backup in case the supplied power source has problems starting up my device.
> 
> The whole thing weighs in at 9.5 lb, and costs under $50. My cost is $0 because it happened to use components that I already had lying around. I'm describing it here for others to copy if they choose. I think it is particularly useful for chartering or camping, where the type and quality of power sources is questionable. If you have something you like better, that's great! If you can suggest something that is guaranteed to work better in my situation, I'm open to hearing about it. I have 2+ months to test it out.


I stand by my statements. Its only my opinion , which I beleive I am allowed to have and state.

The definition fits even your explaination to a tee.

Wikipedia › wiki › Jury_rigging
Jury rigging refers to makeshift repairs or temporary contrivances, made with only the tools and materials that happen to be on hand, originally a nautical term.


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## bacinmass

Long-time CPAP, VPAP, and APAP user here. You may want to check with the CPAP manufacturer. I have found various machines were easier/harder to deal with in this regard. It seems that sometimes their electricity requirements are strangely specific, bringing sine waves and other aspects into the equation that I'd never heard of. I have found the manufacturers to be pretty helpful with deciphering their machine's specific requirements.


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## SVAuspicious

Hi Rick,

I've had a number of crew with CPAP machines. The biggest issue is 12, 19, or 24 VDC underlying power. It sounds like you have that part sorted. 

It seems silly to me to convert 12 VDC to 117 VAC just to convert it back to 12 VDC. My solution has been to carry about 25' of 10 AWG duplex wire with big ring terminals to hook to the batteries (wherever they are) and whatever connection is needed at the CPAP end. Works a treat.

Doesn't hurt to get a gander at the batteries and make sure the water is topped up on a charter boat anyway.


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## TakeFive

SVAuspicious said:


> Hi Rick,
> 
> I've had a number of crew with CPAP machines. The biggest issue is 12, 19, or 24 VDC underlying power. It sounds like you have that part sorted.
> 
> It seems silly to me to convert 12 VDC to 117 VAC just to convert it back to 12 VDC. My solution has been to carry about 25' of 10 AWG duplex wire with big ring terminals to hook to the batteries (wherever they are) and whatever connection is needed at the CPAP end. Works a treat.
> 
> Doesn't hurt to get a gander at the batteries and make sure the water is topped up on a charter boat anyway.


Dave, thanks for sharing your experience with this. I've finally gotten back to working on it.

I happen to have a 25 ft. Battery Tender extension cord that's designed to work with the other components that I linked previously. It's not 10 gauge, but I think it should be sufficient for my 7 watt CPAP blower.

The Battery Tender battery harness that I linked comes with ring terminals out of the box, but they are ever so slightly smaller than 3/8", so they won't fit onto a typical 4D battery's posts. I happened to have a few 3/8" crimp-on ring terminals in my parts bin, so I made a couple ring terminal pigtails to convert from the F2 terminals that I had already spliced on. So I can use the same wiring harness to connect directly to the boat's batteries as you suggested.

Since I am ultra-cautious about having a working CPAP, I might still bring the UPS battery that I showed previousl,y as a backup. (It may depend on how much other gear I want to bring.) To use the UPS battery, I'll just remove the pigtails and attach the F2 connectors onto the UPS battery tabs.

I have some nice Ancor terminators that end in both rings and F2 tabs (typically used for connecting two wires to a single breaker inside a 12v panel), but in this application it would have involved having energized ring tabs exposed while using the F2 tabs. I decided that was a no-go.


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## SVAuspicious

TakeFive said:


> Since I am ultra-cautious about having a working CPAP, I might still bring the UPS battery that I showed previousl,y as a backup. (It may depend on how much other gear I want to bring.) To use the UPS battery, I'll just remove the pigtails and attach the F2 connectors onto the UPS battery tabs.
> 
> I have some nice Ancor terminators that end in both rings and F2 tabs (typically used for connecting two wires to a single breaker inside a 12v panel), but in this application it would have involved having energized ring tabs exposed while using the F2 tabs. I decided that was a no-go.


Can you fly with the battery?

For your boat you might consider Anderson powerpole connectors from Powerwerx. Powerlet connectors, also called BMW power plugs, are another good option. Both are way better than cigarette lighter plugs.


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## TakeFive

I will look into those connectors.

The battery is SLA, not lithium chemistry. I could not find anything on FAA website prohibiting that type of battery, but I understand the concern. That's part of the reason I wanted a $13 battery, in case I need to leave it behind somewhere. But, of course, then comes the question of how to dispose of it so I'm not fully stopped from making the trip. I'll need to check further. I suspect I'm not the first person who has tried to do this.


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## Minnewaska

I once had a guest along, who used a CPAP. He had a rechargeable battery that he used each evening and we recharged it during the day. No wires through the cabin, no standing on your head and rubbing your belly. No brainer. 

The spare from the charter company sounds like a great idea, as long as it can be conveniently charged aboard. My guest's must have had a built in charger. It's been a few years and I can't recall if we charged off 110v or 12v.

I not only prefer to travel light, I've grown to insist upon it. Hauling a lead battery would be a serious buzz kill for me. All the best sorting this one out.


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## TakeFive

The best batteries (high energy content in small, light package) are various forms of lithium chemistry. Unfortunately they are getting a bad reputation for catching fire (especially on airplanes), and thus difficult or impossible to get one of the needed capacity on an airplane. And they would be very expensive for this one-time trip.

The UPS battery that I am considering taking weighs under 10 lb. There are no formal restrictions on SLA batteries on planes, though I will check into it further. I'd like to avoid it completely, but after having a few failures when using other people's batteries, I may prefer to take one that I have tested at home and have confidence in.


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## Minnewaska

Think about mailing the battery to the charter company well in advance.

I refuse to check baggage, when heading to the Caribbean to charter.


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## TakeFive

We're not chartering under our own names. We're enrolled in a sailing course. The sailing school does the chartering, and they're out teaching for 7-10 days at a time, so there may be nobody to receive shipment. In other words, too many middlemen involved, so pre-shipping anything is far riskier than checking baggage. Fortunately we have a nonstop flight on a major carrier, so checking bags is a little less problematic than transferring to a puddle jumper. But if I take the battery it (and all my CPAP gear) will probably go in my backpack for carry-on. I don't like to check stuff that can't be bought over the counter at my destination (under my travel insurance coverage).

We'll never fly an island puddle jumper again - we learned that lesson the hard way. It's been a long time, but last time we flew Virgin Islands Airways (trying to get home from our honeymoon on St. John) the planes would fill up before getting to Charlotte Amalie and just fly over without even radioing the airport to let them know. We showed up at 8 am for our scheduled flight, but sat in the airport lounge for 10 hours waiting for a plane to land and pick up passengers. We missed our connection in Miami by many hours. The locals seemed to be in on the routine, since they didn't even start trickling into the airport until about 4 pm.


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## serpa4

I'm going to see my doctor this next week to see if this alternative would work. Sounds cool, hassle free, and no power! I sure hope I'm a candidate and so does my wife.
https://www.inspiresleep.com/what-is-inspire-therapy/how-inspire-therapy-works/
When I called in about it, the battery in your chest, is good for about 8 years.
I cannot sleep with my mask at all.


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## twoshoes

A cybernetic implant that involuntarily controls muscle movement. What could possibly go wrong?

"We are the Borg. Resistance is futile. You will be assimilated." 

All kidding aside though, thanks for the link. I'm going to look into it too as I have a CPAP in a closet collecting dust. Tried for weeks using different masks, could never get used to it. It made me feel like I was drowning and I would pull it off in my sleep.


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## serpa4

Drowning, yep. 7 months and I cannot get used to it.


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## TakeFive

For those who feel like they are being "waterboarded with air," I cannot suggest any improvement.

For those who have skin abrasion or irritation from cheap silicone pads contacting your skin, I recommend the Phantom Nasal Mask for best comfort. I've used them for 20 years with great comfort. Every once in awhile a new mask is introduced (nasal pillows, etc.) and some sleep technician talks me into trying it. I've never found anything to work for me besides the Phantom Mask.


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## outbound

Find that some people who failed Cpap didn't have pure OSA(obstructive sleep apnea) but rather CSA( central sleep apnea) or mixed or cheyne stokes ( periodic breathing) from congestive heart failure. Also found people who were intolerant when titration was done with autopap( auto titrating) devices. They would develop emergent central apneas. If you are having trouble either not getting restful sleep with use or nocturnal awakenings try to get an in lab psg followed by an in lab titration. When done by an AASM ( American academy of sleep medicine) certified lab. It remains the gold standard. 
Would rather see people use oral devices and if obese lose weight than give up on treatment.


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## jongleur

I am 6'2" and 172 lbs. Not close to obese
and I have hypopnea. My O2 sat rate is
quite low. I'm looking at:
http://www.thecpapshop.com/respiron...All Products&gclid=CKyM2K6SwtECFQONaQodOy0N-g
Hope it's okay to post this link. Anybody
use this?
Girlfriend slipped a jaw joint with an oral
device. Makes me not want to try that and
apparently mine's not necessarily obstruction,
it's that my respiration rate just slows way
down. Heart rate goes to 50.
I'm reading these posts avidly.
I will be beefing up my house bank on my
next boat to make sure the two of us can
run both units all night.


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## chef2sail

TakeFive said:


> For those who feel like they are being "waterboarded with air," I cannot suggest any improvement.
> 
> For those who have skin abrasion or irritation from cheap silicone pads contacting your skin, I recommend the Phantom Nasal Mask for best comfort. I've used them for 20 years with great comfort. Every once in awhile a new mask is introduced (nasal pillows, etc.) and some sleep technician talks me into trying it. I've never found anything to work for me besides the Phantom Mask.


Having tried a few masks/ pillows over the years , one I tried was the one you recommended, the Phantom Nasal Mask. It was irritating my skin and because of the hose at face level prevented me from sleeping on my side. It was one of the worse I ever experimented with.

I have settled on a dream ware nasal pillow. The trick to the silicone nose pillow is to have multiple ones and sanitize them every few days I have found. Bit to each person has their own requirements.

i think when it comes to masks / pillows/ for CPAP is is a very personal choice as well as fit / the way you sleep/ your tolerance for a full contraption/ nose or mouth breather and to recommend and particular one for someone is foolish. I am lucky the company I deal with has many different varieties and i have had the ability to experiment till I found the one which worked the best for me.

All I can tell you since I started using a CPAP years ago, my sleep apnea is not there and I feel well rested all the time now.

Back to the use on a trip on which I highly agree with Rick is upmost important to have a functioning machine, I have invested in good lithium backups as well as proper D.C. Conversions for charging in any situation. It is necessary also because of the flying I do and staying in hotels, the electrical outlets are not always in kind spots for my machine. I have never had an issue with my battery packs in my checked luggage .

The draw on my machine is fairly low after initial startup especially without the humidifier part and my battery packs will last at least 10 days without a recharge.

To me it's easier to do it thus way as my units next to me and their are no operating wires strung accross a cabin or pulling the battery compartment of a boat apart to run my machine.

We are chartering in Grenada in a few weeks. I don't know how close I am to the batteries in our sleeping quarters nor do I care. I will have my battery packs with me and I am sure during the day I can recharge from any one of the outlets in the main cabin should I have the neeed to which I probably won't.

Funny story. One time when going through customs. They had they X rayed my luggage in the compartment and they saw the batteries, Charger with wires and I was called out of the line to a room to explain. I pack the machine and batteries all together in the suitcase so it was easy for them to get the picture.

I decided to go with this set up and not jury rig one because I will always use it and yes the batteries can be expensive, in the long run over the years I have had them the cost is minimal and there is not angst or worrying about it wherever I go or travel.


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## TakeFive

A quick update on my plans to arrange for CPAP use on my Cruise and Learn training in two weeks:

I got the charter boat info from the sailing school, and called the manager of the charter base to discuss the boat's power options. I described to him how I need to know whether a 12v outlet is available in any/all of the berthing areas. He told me my timing was perfect, because the boat was at the base, so he'd go check before it left and get back to me. He wrote back today that he had checked it, and yes, every berth has 12v USB charging outlets. I wrote back and told him, "Thanks for checking, but unfortunately USB outlets are only 5v and won't power a CPAP. Could you please go back and check for real automotive-style 12v outlets?" Unfortunately, the boat is out for a week now, so he can't check again.

So I'm back to figuring out how I can take my own battery along, since I want to be 100% sure this thing will work. (I'll still bring a long wiring harness, but sometimes the long wiring causes problems.) I've rechecked FAA and carrier restrictions on batteries, and now I'm seeing different web pages that say some larger Li ion batteries are allowed. Some of these pages were recently updated, but some others are older. It's so odd that Google seems to bring up different pages than it did a couple months ago, and they're saying different things than they were before.

Additionally, I've found a 11Ah Li ion battery pack on Amazon for about $65. It's 1.6 lb, vs the 12 Ah SLA battery that I have that's 9.5 lb. The listing for it specifically mentions that it's designed to work with my CPAP model, though clearly it's a Chinese thing that's not certified. (The "medical grade" battery pack for my CPAP is close to $400.) So for $65 bucks I have a solid backup option that I can take with me on the plane, and use on my boat in the future (since I have no 12v outlet in our V-berth). I'm ordering it tonight, will test this week and let all of you know.


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## jongleur

Looking forward to your reports.


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## SVAuspicious

It's kind of cool that the charter company has responded to common need and put USB charging ports in every cabin. 

A little time with a screwdriver will get you 12 VDC behind those ports as well as lights and fans.


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## TakeFive

SVAuspicious said:


> ...A little time with a screwdriver will get you 12 VDC behind those ports as well as lights and fans.


Yes, that had occurred to me. I tend to keep some of my more "creative" ideas private, especially when they involve others' boats.  Let's just say that I've added a screwdriver and alligator clips to my packing list.


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## Minnewaska

You might want to check with the airline for any restrictions over carrying an Li battery aboard.


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## TakeFive

I called and talked to them on the phone. With the web page in front of me, I asked what the policy was, and what they read me was exactly what the web page said. For Li-ion, I can bring up to two batteries of up to 160Wh each. For SLA, it merely needs to say "non-spillable" on the case, and be protected against short circuit across the leads while in transit.

I've put the Amazon order on hold for a day or so while I decide. I just don't trust the Chinese guys to design a high energy battery that is safe from overheating. But the SLA battery (effectively a wheelchair battery) is so heavy, and bound to get unwanted attention from security, even though I'll have a printout from the web page saying it's allowed. So I'm thinking about it.


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## TakeFive

I went ahead and pulled the trigger on purchase of the Li battery pack. It has four lights to indicate charge state (15-50-75-100%). The first night of use it went from four lights down to two. I ran it for a second night, and it stayed at two lights. (Doesn't totally make sense.) I was in too much of a hurry to put a volt meter on it for better reading. No appreciable heat buildup on the battery pack during the discharge. It comes with an adapter cable that is a perfect fit for my Respironics CPAP.

Discharge rates will depend on model of CPAP and pressure setting. I recommend putting a kill-a-watt meter on it (and any other boat accessories) to understand energy needs.

This battery pack looks like a winner so far. Next test is to use it for a night and try charging in my car on the way to work (instead of off the AC adapter).

https://www.amazon.com/gp/product/B016BJCRUO/


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## travlin-easy

While my wife uses a CPAP onboard that I run from the inverter, I now have an oxygen generator that has a couple LI batteries, each of which will only last about 2 hours at best. The device also came with an auxiliary power supply that plugs into a cigarette lighter socket. However, it draw 17 amps while running, which for me is most of the time. Fortunately, my boat has about 570 AH of batteries, 500 of which are house batteries. Therefore, I will be able to run it through the night, which is when I need it most, without worrying about draining the house batteries completely. This getting old crap is not all it's cracked up to be, especially when vital body parts go to Hell. 

All the best,

Gary


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## Minnesail

TakeFive said:


> Let's just say that I've added a screwdriver and alligator clips to my packing list.


It was before my day, but I remember hearing stories of the first portable computer road warriors running alligator clips from their modem cables and making discreet slits into the cords of pay phones so they could get dial-up. Probably in the 300 baud days 

Anyway, I've been following your posts, thank you for them. My wife really likes her CPAP, but only when the humidifier is going. If there's no humidifier she'd rather go without it. I know the heat required for the humidifier ups the necessary wattage quite a bit, but I wonder if these newly cheap lithium batteries you're describing would do the trick. Thanks again for the info.


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## TakeFive

We returned from our Caribbean training a couple weeks ago, but have been too much on the run to post. My idea to remove the USB charger socket to access the 12v wiring was thwarted by their use of Torx screws. I guess they were wise to my plans.

The lithium battery pack linked above worked perfectly. It even came with a cable specifically designed to plug into my CPAP. I printed out the web pages to show that it was within the power limitations set by the airline, but everything sailed through TSA with no questions asked.

For anyone who buys this battery pack, I have two suggestions:

Place some duct tape over the 9v out socket. Accidentally plugging a 12v charger into this socket can severely damage the unit, and it's not labeled that clearly, so the two sockets are right next to each other.

Also, you should buy the company's 12v charger instead of using a generic one. The 13.8-14.1v put out by typical alternators can damage the battery pack, and their 12v charger has a voltage regulator to prevent this damage.


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## JustRelaxing

TakeFive, thanks for the information on what you did. This is really helpful. I have a couple of questions if you don't mind. I have a ResMed AirSense 10. The output from the power supply is 24v DC. The battery you found is 12v DC. Is your CPAP input 12v or did you "convert" to 24v. ResMed sells a DC adapter for 12v input but it's (a) expensive $85 and (b) most importantly it has a cigarette lighter connection or alligator clips. I'm trying not to run wires through the boat. ResMed warns against using 3rd party DC adapters as they claim the polarity is different from what they need. 

I appreciate all the information from everyone, especially about not trying to use an inverter which really does not make any sense. I did confirm from Sunsail that we will only have USB outlets in the cabin. Thanks for any additional suggestions.


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## TakeFive

JustRelaxing said:


> TakeFive, thanks for the information on what you did. This is really helpful. I have a couple of questions if you don't mind. I have a ResMed AirSense 10. The output from the power supply is 24v DC. The battery you found is 12v DC. Is your CPAP input 12v or did you "convert" to 24v. ResMed sells a DC adapter for 12v input but it's (a) expensive $85 and (b) most importantly it has a cigarette lighter connection or alligator clips. I'm trying not to run wires through the boat. ResMed warns against using 3rd party DC adapters as they claim the polarity is different from what they need.
> 
> I appreciate all the information from everyone, especially about not trying to use an inverter which really does not make any sense. I did confirm from Sunsail that we will only have USB outlets in the cabin. Thanks for any additional suggestions.


I have two CPAP machines, and both run off of 12v, which simplifies things greatly. My newer one is 12v only (had external power brick for 120v), and is very efficient at about 7 watts. My older/bigger/heavier one, which runs 120v primary with a 12v socket in the side, is apparently much less efficient, which I learned the hard way when the battery pack died in the middle of the night. I need to stick my Kill-a-watt meter on it and do some calculations to understand, as it's the older one that I keep on the boat in the hostile environment.

I don't really know what to say about your 24v requirement. It may be hard to find a lithium battery pack for that. You can find step-up transformers that plug into an automotive socket (including the "genuine" one you mentioend), but you may have a long wire run since you only have USB connectors in the cabins. That's why a lithium pack was such a great find for me.

I'm not real familiar with your model of CPAP, but make sure you can turn off the heated humidifier, since that will run down even a hefty boat battery way too fast. If you have time, I'd suggest buying a Kill-a-watt meter and seeing how much power it draws off of AC. You want to size any battery pack with enough mAh to power for two nights. That way if you forget to recharge one day, you can get through the second night.


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## redfishnc

I have the same Resmed and I bought the 12v adaptor from a independent dealer in OHIO, about 75 bucks. I like the ease of plugging it in. Could one reason for not removing the USB plug be the wiring may not be up for heavy 12v draw??


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## TakeFive

redfishnc said:


> I have the same Resmed and I bought the 12v adaptor from a independent dealer in OHIO, about 75 bucks. I like the ease of plugging it in. Could one reason for not removing the USB plug be the wiring may not be up for heavy 12v draw??


USB only puts out 5VDC - not enough voltage for any CPAP device.


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## TakeFive

TakeFive said:


> I have two CPAP machines, and both run off of 12v, which simplifies things greatly. My newer one is 12v only (had external power brick for 120v), and is very efficient at about 7 watts. My older/bigger/heavier one, which runs 120v primary with a 12v socket in the side, is apparently much less efficient, which I learned the hard way when the battery pack died in the middle of the night. I need to stick my Kill-a-watt meter on it and do some calculations to understand, as it's the older one that I keep on the boat in the hostile environment...


Just to close the loop on this, I tested the older unit with the Kill-a-Watt meter, and it averaged out to 14w, so its power draw is double what the newer one is. This explains why the battery pack did not last through the night. It also means that I should bring the newer CPAP with me anytime I'm sleeping on the hook. It even draws 3w just at rest when plugged in, which is almost half the power draw of my new one when it's running.

I strongly suggest that people get a Kill-a-Watt meter and test out everything that you use on the boat to understand how much it is drawing down your batteries. There are several models, but this older one does a good job at a lower price point than the newer ones:

https://www.amazon.com/gp/product/B00009MDBU/

One thing about CPAP is that the wattage will fluctuate, typically drawing higher watts for inhale than exhale. So you should press the button to integrate kW-h over a full night of sleep, then divide by the hours you slept to determine power draw.


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