Battery Backup?

cpaptex · Post by **cpaptex** » Mon Jan 09, 2012 1:24 pm

I don't think that I would do anything beyond buying a Full Sine wave UPS that would run for 20-30 minutes and cover 99% of all power outages. It would also start to chirp immediately when the power went out. Total cost $150 - $1000. You could get a lot minutes if your willing to pay for it. Once it starts to chirp, I'd turn off the heat on the humidifier.

Just my thought...

JohnBFisher · Post by **JohnBFisher** » Mon Jan 09, 2012 1:44 pm

cpaptex wrote:... I don't think that I would do anything beyond buying a Full Sine wave UPS that would run for 20-30 minutes and cover 99% of all power outages ...

As you note, the answer to what we need is highly individualized.

Length of Power Outage:

Some people live in an area where a natural disaster can wipe out power for a day or more. So, each of us must ask ourselves if we might have a power outage due to:

Severe thunderstorms
Snow and/or ice
Hurricanes
Tornadoes
Earthquakes

If the answer is yes to more than one of those, you should plan on having a battery backup (or alternative plan) to cover one or more days.

Let's face it, most of us can handle one or two nights of poor sleep. We might have friends and/or neighbors who still have power. We might try to rent a hotel room - assuming they also have power. But if it is likely to loose power for extended periods of time due to natural disasters, it would be wise to plan on more than one day of power outages.

If that rarely if ever happens to you (in your area of the country), then certainly a UPS would be a decent alternative.

Heated Humidifier Requirement:

As you note, most of us can live without the heated humidifier for a while. We would need it if we live in an area of the country that is fairly arid. For example, if you live in a part of the country / world where evaporative cooling (often called swamp coolers) is a decent option for cooling a house, then you probably need a heated humidifier. Surprisingly, such arid conditions do not equate to desert conditions. For example, the high plains before the Rocky Mountains is a good example. I've seen about 12 inches of snow literally evaporate, rather than melt.

However, other parts of the world have amazingly humid conditions. I live in such an area. Even our driest days are far more humid than very wet days in some part of the world.

An Individual Need = An Individual Solution

So, the needs I have may not be the needs that another has. Though you are definitely right that few of us really need any major backup power solution, this is a case where "your mileage WILL vary". Fortunately, with this site we get to hear from the experiences of others. It helps sort out what works and what does not.

archangle · Post by **archangle** » Mon Jan 09, 2012 1:50 pm

Some of the M series humidifiers run directly off of 120VAC. There's a good chance these will be damaged by an AC inverter, an all-in one jumper/AC unit, a portable generator, or a UPS. All of these usually generate what are called MSW waveforms.

ResMed warns their AC powered S8 humidifiers will be damaged by MSW power. The blower unit is OK, only the humidifier heater is a problem. I have not seen a statement on MSW from Respironics.

Some M series humidifiers are AC powered, some are DC powered. Apparently, they changed somewhere in the middle of production of M series CPAPs.

ResMed says S9 humidifiers are OK since they're powered on DC from the power brick. I presume PRS1 humidifiers are OK for the same reason, but haven't seen any statement on MSW safety from Resmed, even for the blower unit iself. .

Paul56 · Post by **Paul56** » Mon Jan 09, 2012 3:00 pm

JohnBFisher wrote: A caution about a generator (like the Honda listed), it does not produce a pure sine wave. It produces a modified sine wave.

It also produces DC output which can be input into a pure sine wave inverter
and out pops pure sine wave AC power.

JohnBFisher wrote:Further, as with all generators, they are an outdoor only item (or at least an open garage).

Uhm, ya... I figured everyone would realize that.

JohnBFisher wrote:Though it is listed as "super quiet", 53 to 59 dB is not all that quiet - at night! It would be similar to someone talking in a normal conversation outside your house at night. You would notice it. It's not too intrusive, granted. But it would be noticeable.

These generators are quiet enough that street buskers with electrical musical
equipment use them to power their instruments.

Now, if one has a garage or shed that is vented this unit inside that structure will
not be keeping the neighbors or you awake at night. In any case it will go a long way
to smooth things over with the neighbors by sharing the power during an outage.

Those who lived through the great ice storm of 1998 with a generator came to appreciate
the value of that generator... as a battery backup just will not cut it for multiple nights.

I can sleep while the TV is mumbling away in the background and can sleep while this
generator operates through the night... used to have one at my cottage.

ProfessorEd · Post by **ProfessorEd** » Mon Jan 09, 2012 5:00 pm

archangle wrote:Some of the M series humidifiers run directly off of 120VAC. There's a good chance these will be damaged by an AC inverter, an all-in one jumper/AC unit, a portable generator, or a UPS. All of these usually generate what are called MSW waveforms.

ResMed warns their AC powered S8 humidifiers will be damaged by MSW power. The blower unit is OK, only the humidifier heater is a problem. I have not seen a statement on MSW from Respironics.

Some M series humidifiers are AC powered, some are DC powered. Apparently, they changed somewhere in the middle of production of M series CPAPs.

My humidifier operates off of AC power and a cable from there connects to the Bi Pap machine. The connector on the machine is a 3 prong device (it appears the small prong carries information from the machine to the humidifier to change settings) and as I mentioned the power brick states it outputs 26 volt power and the machine that it uses 24 volt.

I spent a long time on the phone with a nice lady at CPAP.com, who described the solutions which involved two Respironics products, with a cigarette light type connector between them, each costing about $25. However, from the pictures on their web site the output was to a connector that looked like one prong, not the 3 prong my machine takes. She eventually gave me the number for Respironics.

As you may know Respironics is not licensed to sell medical devices in the US to consumers, and their recording tells you that. However, they will speak to you and from her I learned they had Part #1012975 (list at $165) "RP-DC Power Adapter Kit for Respironics Bipap Machines" which has the right connector for my BiPap machine. This consists of two parts, one with alligator clamps to a cigarette type connector and then another from a cigarette connector to my machine with box in between that Respironics lady did not know what it did (and had trouble understanding what I was talking about). They do not sell the part separately that would go from say a car cigarette lighter to your BiPap.

There is another part 12 Volt DC Power Cord (connects CPAP to cigarette lighter socket) which costs relatively little $25, but judging from the picture of the connector will not power certain machines, including mine. The description states it power all "All Respironics M Series Machines" but further down indicates it " This cable cannot be used with the Respironics REMStar BiPAP Auto, BiPAP Auto ST, BiPAP Pro 2 or the BiPAP Plus. You will need to purchase the RP-DC Power Adapter Kit." Hence it is possible my machine is technically called a REMStar BiPAP Auto even though it looks like the M series machines pictured on various sites.

Thus it appears that for those with my machine $165 would be needed to connect the machine to a marine battery.

It appears I might be able to run the machine off of my AC current from my power supply, but it produces a modified sine wave which apparently would be bad for the humidifier. I do not know whether turning the humidifier off (or at zero) would protect it. I am not clear why a modified sine wave would hurt the humidified (which I would have thought was a simple heating element). Assuming it would a key question is whether setting it on zero bypasses the damageable part, or there is still a risk. Anyone know?

I am rather irritated at Respironics. Their lady while friendly enough was clearly not technically informed. She claimed their equipment ran off of 12 V power, but given the statements on my machine about it being 24 volt, I doubt her. I cannot explain the high cost of the cord required unless the "box" in the circuit step 12V power to a higher voltage. (24V). Almost certainly the RP-DC Power Adapter Kit duplicates much of the electronics in the power brick, and at very low cost they could have provided a way to input 12V power.

If the machine requires 24V power (as the bottom states) it should be possible to put say two 12V batteries in series to provide it. (I have two such batteries, but am a little nervous about doing so given lack of knowledge about just what is required). I am fairly certain there are lower cost solutions than $165 for powering my machine from 12V batteries I already own.

Respironics should provide their representatives with enough information to know what voltage their machines uses. Hiding behind not licensed in the US is a problem. DME suppliser lack the incentive to provide high quality information, especially for those who bought their machines from another, or who are ex-customers (insurance companies can and have forced changes of suppliers on me). They may also be aware that you may milk them for information and then order some items not covered by insurance (such as the cables, battery packs etc. from another). Respironics could easily put out detailed technical information, and put it on the internet for the rather common desire to have a DC supplied device.

My current supplier is poorly informed for my issue (she apparently has only handled machines with DC inputs on them, and seemed unwilling at first to believe me when I asserted my model lacked such).

I had some trouble getting this machine. After the doctor wrote a Auto BiPap prescription America's Health Care at Home delivered a machine I could see clearly was not the right one, although their set up representative did not seem to know what one should look like. I managed to send it back, and expected the new machine to be their latest model. After the delivery, I realized I had what was then called the "tank" model. At the time there was considerable discussion on this site about the relative merits of the older and new models, and I decided not to fight the DME over the issue, although it looked like they had again made a mistake and were unloading their older inventory on me. I notice a sticker saying BiFlex in green on the top, suggesting they had not modified the case when they added this feature to the innards. Close inspection of the case shows there appears to be a knockout piece which would permit a second connector, probably a DC one.

archangle · Post by **archangle** » Mon Jan 09, 2012 5:22 pm

Paul56 wrote:
JohnBFisher wrote:Further, as with all generators, they are an outdoor only item (or at least an open garage).
Uhm, ya... I figured everyone would realize that.

Don't run it in an open garage either. Every time there's a widespread power outage, there are a few families who die because they ran their generator in an open garage attached to the house.

GumbyCT · Post by **GumbyCT** » Mon Jan 09, 2012 5:36 pm

archangle wrote:Don't run it in an open garage either. Every time there's a widespread power outage, there are a few families who die because they ran their generator in an open garage attached to the house.

Finally something we CAN agree on. The it above refers to a generator. Which emits carbon monoxide and can be blown into the house even when the generator is placed outside but not far enuff away from the house.

fwiw - generators can kill you quicker than OSA.

GumbyCT · Post by **GumbyCT** » Mon Jan 09, 2012 5:42 pm

Also instead of worrying about whether an inverter is compatible with a humidifier - either use it in passover mode or buy one of the many humidifiers which will work on 12V. As mentioned some of the M Series humidifiers are 12V, ALL of the System Ones are 12V, and I think Re$med is finally catching on but then their adapters are pricey.

Are their machines 24V and the humidifier 12V? To me it's much easier to buy something that will work on 12V, period.

Hose_Head · Post by **Hose_Head** » Mon Jan 09, 2012 7:39 pm

ProfessorEd wrote:I like many have been concerned about a backup CPAP backup power source for power failures and the ability to run my machine during camping.

My first attempt involved buying a large marine battery (marine was suggested because they are designed for slow drain applications like warning lights on sailboats, while auto batteries are designed for a short burst of power to start the engine). I spent about $200, plus buying a converter to convert to alternating current and a way to charge it, struggling with various connection problems. A friend helped me with a solution? that involved two wires, one on each terminal. I never was able to run the machine off of this set up.

Recently I bought a "Schumacher XP2260 Instant Portable Power Source" from Amazon for about $100 after noting that in the review one person mentioned using it when camping for her husband's CPAP machine. I have confirmed it runs my machine.

This device (and there are others) is multipurpose being basically a lead acid battery with jumper cables to start dead cars (which was what I was searching for). However, it also had a 400W inverter stated able to provided 120V of household power (and two standard sockets you could plug things into, such as my machine), an air compressor (for tires), power sockets for 12V accessory power (the type of connectors a car has) and a USB port, and a three diode built in light. It also has built in recharging equipment so you can plug it in at home and assorted gages etc. While no cheaper than single purpose solutions, the multiple uses may make it a better purchase.

This seemed like a worthwhile investment since it met both my need for jumps starting a car and for emergency and camping CPAP power, and could be used for other emergency purposes or camping when power was needed. Of course, the total package is bulky and heavy (11.8 lbs), but meeting several needs at once made it attractive, and a solution some may not have thought of. It could be carried in the car for emergency uses and brought inside only when needed for power failures.

The same brand offers portable power supply without built in jumper cables (which might be safer with children around) and no air compressor for only $85. It might be possible to buy separate jumper cables that would be inserted into the 12 volt outlet (which would be safer since children might not figure out a way to shock themselves with the jumper cables). There is a Duracell brand item with more power and a much higher price ($169.95).

One question I have is how to make use of the large investment in the marine battery which I never could make work and indeed presented a safety hazard (I got sparks trying to recharge it from this device due to an unnoticed short from the stripped wares touching.) This device may not have enough power to run my machine for more than one night (although its portability rising the possibility of taking it somewhere with power and recharging (i.e. work). Observation shows the recharging rate is slow (perhaps less than 10% over 8 hours), but a full day at the office would help, and the built in handle means carrying it to and from a car would be practical.

From comments I gather with the right connector you can recharge this from you car power sources (cigarettes lighter)while driving (i.e. useful on long car camping trip where you would recharge it while driving. Presumably this might also be done if one drove to work or somewhere during a power outage (I do not know how long this would take). From the warning in the instructions about no overcharging, it appears this just establishes a direct connection with your car's electrical system (and there is nothing to limit the current flow or prevent overcharging while when recharged from household current there are circuits to prevent this). I do not know how long this would take, and any advice from someone with better knowledge would be useful (for instance could you recharge it just by running the car for a short time or during a fairly short commute or shopping trip.

A table on Amazon for the Duracell line of similar products suggests recharging time of 2.5 hours to 4 hours using direct current, so that full recharging would be unlikely on short commutes, although partial recharging would be useful, and full recharging would appear possible on long trips. If willing to leave the car idling for hours in the driveway, full recharging wold appear possible. The required male to male connector appears to cost only $5.37, so I probably should buy it just to have the option.

There should be a safe way to connect the two batteries so they would act as one, although I am not quite sure what product is needed. Putting the two jumper cables on the marine battery terminals would seem to do this, although I am do not know whether there is something that would prevent this from working (blocking a reverse current flow somehow). Also, if I found a connector with a cigarette lighter type connector on one end, and two clamps that could connect to the marine battery, I believe both would function as one battery, giving me a larger power capacity (and I might be tempted to use one of the outlets for some other power need when the snow or other storms cut power to the house). I could get a connection using a Roadpro 12V Battery Clip-On and Cigarette Lighter Adapter ($5.60) and then a RoadPro RP-203EC 12V 12' Extension Cord with Cigarette Lighter Plug ($8.97) or the male to male connector mentioned above, but there should be a device with a cigarette type male plug on one end and clips for the battery terminal on the other, although I have not found it. I do not know if the above solution would be any better than just putting the jumper cables on the other battery.

I also have some concerns as to the status of the marine battery, which has sat unused for several years. I have been charging it by connecting it to the Instant Portable Power Source at night, and then recharging the power source (the manual says not to try to use the device while it is plugged into the wall sockets). I am not sure what shape it is in or how to determine that. My new device provides a voltage measure which appears to show a 13 Volt on the battery, suggesting it is still good.

I am presuming the Instant Portable Power Source output will power the Respironics Bipap for a longer period (I just tested it for a few seconds to confirm it did work). I notice the manual describes it as producing a nonsinusoidal wave form .

I have some safety concerns since I have children at home and 12 V batteries can give shocks or produce fire starting sparks. The device I bought has a switch to turn off power to the jumper cables, but the marine battery terminals are exposed (I have then covered with duct tape now to prevent problems).

Too bad about your difficulties. You were nearly there. From your sig file, you are using an M Series xpap from respironics. Good news is that these xpaps will run directly from a 12 vdc battery. You didn't need to buy an inverter. What you do need, however, is a cable that goes from battery to your M Series. You can make one up but the simpler solution is to just buy one from CPAP.com.

Important note: unless it's one of the very largest batteries you can buy, a marine battery is unlikely to provide enough power for an xpap AND humidifier for more than a couple of nights. If you turn off the humidifier, you can get much longer run-time from the battery.

For your battery, you need a proper deep-cycle battery charger. This is necessary to ensure that the battery is recharged properly so that it is not damaged by improper charging. A correctly sized charger will recharge the battery in just a few hours. Alternately, a trickle charger also will work (see John B Fisher's post, above); it will keep the battery charged for when you need it and over a period of a few days, will recharge a discharged battery.

BTW, marine deep cycle batteries are not the best choice in this application. They are kind of a hybrid between a true deep cycle battery and a car battery - designed this way because they also are used for starting boat engines. A better battery type is a gel cell or glass mat battery designed for use in wheelchairs (can be bought at walmart, etc). Your marine battery will work, but it won't have the run-time or longevity of a true deep cycle battery.

Also, you should have your marine battery tested to see if it's still good (most garages can test it); they don't last forever.

archangle · Post by **archangle** » Mon Jan 09, 2012 7:43 pm

Did the Respironics person say you shouldn't run the humidifier off an inverter? Did they use the "modified sine wave" term? I haven't ever heard any info on that from Respironics before.

I guess it's possible the M series or Legacy humidifiers can handle MSW, but I wouldn't bet on it.

As to why a MSW waveform might damage a humidifier, a humidifier is not just a resistive heater. It's a resistive heater plus a control circuit. The control circuit is designed to work with a normal AC waveform, not a MSW, which is really a modified SQUARE wave not sine wave. It's much like a lamp dimmer circuit which has problems handling strange voltages or strange loads. Look up Phase Fired Controller if you want details. The circuit might not be able to properly regulate the power to the heater, or it might even damage the control circuitry.

Paul56 · Post by **Paul56** » Mon Jan 09, 2012 7:58 pm

archangle wrote:
Paul56 wrote:
JohnBFisher wrote:Further, as with all generators, they are an outdoor only item (or at least an open garage).
Uhm, ya... I figured everyone would realize that.
Don't run it in an open garage either. Every time there's a widespread power outage, there are a few families who die because they ran their generator in an open garage attached to the house.

That would be an open attached garage... and would be a poor construction
issue as attached garages should be air sealed from the house even though
many are not.

archangle · Post by **archangle** » Mon Jan 09, 2012 8:09 pm

Hose_Head wrote:
Too bad about your difficulties. You were nearly there. From your sig file, you are using an M Series xpap from respironics. Good news is that these xpaps will run directly from a 12 vdc battery.

Early production runs of M series used AC power for the humidifier. Later production runs use DC. I think more of them use AC than DC.

Hose_Head wrote:BTW, marine deep cycle batteries are not the best choice in this application. They are kind of a hybrid between a true deep cycle battery and a car battery - designed this way because they also are used for starting boat engines. A better battery type is a gel cell or glass mat battery designed for use in wheelchairs (can be bought at walmart, etc). Your marine battery will work, but it won't have the run-time or longevity of a true deep cycle battery.

Not true. A deep cycle marine battery will have similar longevity to a AGM or Gel cell battery. There are some marine "Dual purpose" or "Starting/Deep cycle" batteries that are somewhere between a true deep cycle and a car battery. There are even "marine starting" batteries, which is just a car battery with a phony "marine" term attached to it to make you think you're getting a higher quality battery.

AGM and gel cell batteries are preferable to a wet deep cycle battery because they can't spill and may be a little more rugged. On the other hand, all batteries, even AGM and gel cell do lose a little water over time. You can top up the wet cell battery if needed. If you can avoid spilling it a true deep cycle wet battery probably costs enough less to be worth buying it.

Even a car battery will run your CPAP just as many nights in a row if it has the same number of amp hours. The problem is that it will wear out faster than a deep cycle battery, especially if you run it down.

Hose_Head wrote:For your battery, you need a proper deep-cycle battery charger. This is necessary to ensure that the battery is recharged properly so that it is not damaged by improper charging. A correctly sized charger will recharge the battery in just a few hours. Alternately, a trickle charger also will work (see John B Fisher's post, above); it will keep the battery charged for when you need it and over a period of a few days, will recharge a discharged battery.

As someone here once corrected me, you really need a good "float" charger, not just a "trickle" charger. Trickle chargers are less damaging long term than "dumb" chargers, but a true "float" charger is even better.

I use a low current "float" charger for my batteries. I've lost batteries from "smart" chargers that would quickly charge the battery when they sort of lost their mind and cooked the battery anyway. The low current charger is a lot gentler on the battery. If I ever DO get a case where power goes out for a while, comes on for a few hours, and then goes out again, I may regret my choice.

There is some "black magic" in getting a good battery backup system. You may be tempted to buy an all in one "solution", but that doesn't necessarily solve the problems. You may very well by an expensive, prepackaged solution from a slick, well known manufacturer and end up with something that's inferior to a roll your own solution.

I have two strong suggestions for anyone using a deep cycle battery.

1) Be SURE there is a fuse at the battery.
2) Put it in a battery box with a lid on it so that nothing can hit the terminals and short them out. Good battery boxes are cheap and easy to find.

idamtnboy · Post by **idamtnboy** » Mon Jan 09, 2012 8:12 pm

ProfessorEd wrote: I had some trouble getting this machine. After the doctor wrote a Auto BiPap prescription America's Health Care at Home delivered a machine I could see clearly was not the right one, although their set up representative did not seem to know what one should look like. I managed to send it back, and expected the new machine to be their latest model. After the delivery, I realized I had what was then called the "tank" model. At the time there was considerable discussion on this site about the relative merits of the older and new models, and I decided not to fight the DME over the issue, although it looked like they had again made a mistake and were unloading their older inventory on me. I notice a sticker saying BiFlex in green on the top, suggesting they had not modified the case when they added this feature to the innards. Close inspection of the case shows there appears to be a knockout piece which would permit a second connector, probably a DC one.

I see you joined almost 5 years ago. Is this the machine you had then? If so, that's close to 5 years ago so you're due for a replacement. Rather than looking at expensive options to power your current machine from a battery why don't you push your doc for a prescription for a new machine? The money you save by not buying the $165 battery solution will go a long way toward the deductible on a new machine. And you'll have an adequate working machine for a backup.

ProfessorEd · Post by **ProfessorEd** » Mon Jan 09, 2012 8:13 pm

A possible alternative for myself and other with BiPap machines for whom the cost of the circuitry is too high may be find an older machine that could be made to work with direct current. In my case, I have an older GoodKnight auto machine, and possibly another older machine which probably could be made to work. A search shows that there is a power cord (see http://www.cpapxchange.com/M21393003-12 ... -cpap.html) for that product, and it appears the connectors are the same as on Respironics 12 V cables. On CPAP.com the price is just under $50. In my particular case this may be a solution, and may be useful for others who had different machine at some time.

The above web description does provide an insurance code, CPCS Insurance Code: E1399. This is a miscellaneous code, but there may be a way to persuade insurance companies to pay for it. The Respironics website (at http://www.healthcare.philips.com/pwc_h ... DME-01.pdf) provides some hints in filing under this code.

My DME claimed there would be no way to get reimbursement for battery cables etc. since there was no code for it, but there does appear to be one.

My plan (LSU Health Plan administered by Cigna) is rather complex, but the $2,000 per year they pay all claims at 100% out of a separate account (where the employer I think just provides that much), and then a deductable kicks in and you pay a percentage. There is no in or out of network distinction for the first $2,000 and I suspect they are more liberal on such claims. Since it is early in the year I have not burned through this and I am considering trying to get a doctor's prescription and having this covered by the insurance and possibly even a suitable battery pack for travel. The problem is complex since I am Medicare primary and it would probably go through them first. Has anyone had any experience in a similar situation.

Exactly what is medically necessary is debatable, but sleeping without your machine is bad for your health and power failures where I live seem frequent.

GumbyCT · Post by **GumbyCT** » Mon Jan 09, 2012 8:46 pm

GumbyCT wrote:
ProfessorEd wrote:Question I have is how to connect the battery units to the Respironics BiPap M model (tank version with a large power brick). I see the transformer unit has 26 volts written on it, so I gather a direct 12 V connection is not going to work.
The M series IS 12V so if you are seeing 26V then you don't have an M.

Check for the model number on the bottom of your machine.

Does it look like this?
https://www.cpap.com/cpap-machine/respi ... -pro2.html

IF your BiPap looks like that it IS 24V. I think they call the connector a DIN plug. I forget whether it is a 3 or 4 pin DIN but is in fact 24 VDC. It converts 12V to 24V is maybe where you are getting confused.

But I do agree for the money you will be much better off to get a new System One BiPap Machine. Then you can get the right adapter cuz the new hires will know what you need.

fwiw - I think the link to the tank bipap at cpap.com now contains misinformation; to wit: the wrong DC voltage. I have alerted JG to check that page.

This PN is what you will need for your BiPap Tank - it is a 12 to 24V adapater -

ProfessorEd wrote:Part #1012975 (list at $165) "RP-DC Power Adapter Kit for Respironics Bipap Machines" which has the right connector for my BiPap machine.

Good Luck Young Man

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