Deep cycle battery backup questions.

I have read many of the threads pertaining to battery backup and emergency power, but my knowledge of electricity and electronics and batteries is 0 so I was wondering if someone can put this in layman's terms and try to explain it to me like I was a five year old. From what I understand I need a deep cycle marine battery a way to recharge the battery if it is used and an inverter to connect to that battery that my CPAP can plug into?? Any help in explaining a basic setup in a way that I can understand it in terms of a product list of things to buy would be helpful I read the one that has the product list for the one guy but that seems a little complicated I have hey resperonics machine and an S nine and I'm just looking to prepare a backup power situation case I need one. Again I have read through the emergency power threds I just don't understand them

Go to discount computer supply and buy a UPS rated for minimum 1300 va but 1900 to 2300 better. Pluv into wall, plug machine into UPS and you are done. Cost 100 to 250 bucks. Safe, easy, protect macbine from surges and brown outs. When batteries finally die extend wire out of machine and connect to 12v battery of choice.

Which Respironics machine? Model name and number (3 digit number on the bottom of the blower unit).....
Can you do without a humidifier at all?
How much do you want to spend?

Have you seen this for the PR S1 machines
viewtopic.php?f=1&t=83597&p=758600#p758163

or this for the S9 machines
viewtopic.php?f=1&t=83597&st=0&sk=t&sd= ... 15#p758986

If you are like me and would want something totally idiot proof...I would just get this one and be done with it.
My eyes glaze over when I see all this battery stuff myself. This one John got multiple nights with and that was with using the humidifier and with a car battery set up...you won't be able to use the humidifier.
http://www.bestcpapprice.com/Compact-Po ... p_516.html
Talked about in this thread where a forum member was even able to use humidifier with it.
viewtopic.php?f=1&t=86960&st=0&sk=t&sd=a&hilit=battery
Look for the posts from JohnO and his reports.

You still would need a connector and the 50 series machines use a different connector than the 60 series machines (which is why I asked which machine)
and the S9 also needs a special converter which I think runs around $80 so if it were me I would just plan on using the Respironics.

You might want to review my Battery Backup Design V2:

viewtopic.php?t=89123

It outlines what you need to know and the steps to take to create a similar battery backup system.

hueyville wrote:Go to discount computer supply and buy a UPS rated for minimum 1300 va but 1900 to 2300 better. Pluv into wall, plug machine into UPS and you are done. Cost 100 to 250 bucks. Safe, easy, protect macbine from surges and brown outs. When batteries finally die extend wire out of machine and connect to 12v battery of choice.

Very bad advice.

VA tells you nothing about how long the battery will last. You need to know amp hours of the battery, or look up the specs on how many watts it will put out for how long.

Extending the wires outside of the UPS may be risky. You're connecting to the insides of a machine that has 120VAC running around in it. Since the 12V supply is not intended to go outside the case, it may not be properly isolated from the AC supply in order to be safe. You could be electrocuted. It's a bit like opening the cover on an electronic device while powered on and poking your fingers on the electrical components.

Also, a UPS may not properly charge an external battery if it's not the battery it's designed to charge.

There are some links in my signature line about how to make a battery backup system for CPAP.

archangle wrote:

hueyville wrote:Go to discount computer supply and buy a UPS rated for minimum 1300 va but 1900 to 2300 better. Pluv into wall, plug machine into UPS and you are done. Cost 100 to 250 bucks. Safe, easy, protect macbine from surges and brown outs. When batteries finally die extend wire out of machine and connect to 12v battery of choice.

Very bad advice.

VA tells you nothing about how long the battery will last. You need to know amp hours of the battery, or look up the specs on how many watts it will put out for how long.

This can work if you're interested in a "set it and forget it" system that will cover short term (maybe an hour or so) blackouts without waking up. And you really have to dig in the specs to see how much long term power a UPS has. For example, a CyberPower PR1500LCD is $300 on Amazon and has 2 17 AmpHour batteries. 34 AH is enough to run a night or so without a humidifier, but probably won't go a full night with humidity. It does have the advantage of replaceable batteries, but I'm not sure how you know your batteries are weakening unless it shuts off prematurely.

archangle wrote: Extending the wires outside of the UPS may be risky. ...

I agree - If you're willing to do this sort of thing, you should start with a proper UPS controller that can manage one or more larger deep cycle batteries.

If you're more concerned about major storms taking down power for a day or more, then a setup like John's works best. It looks complicated but really comes down to a deep cycle battery and a trickle charger (Battery Tender is the best) plus a DC cable for PRS1, or DC/DC converter for S9. Cost can start at under $150.

CapnLoki wrote:... If you're more concerned about major storms taking down power for a day or more ...

Exactly. All of us face different issues.

I used to live in a house that appeared to be fed by two different major power lines in our area. Why? It was near a hospital. We might have the power flicker for a minute or two. But we never lost power. A UPS unit would have worked fine.

Now I live in an area (as does most everyone on the US eastern seaboard) that can loose power for days on end. Why? Because of hurricanes. Sure, I have a generator. But I can not leave that running all night (or at least should not). So, a battery that can last for a few days is not a bad idea for us.

But you might find a UPS would work for you. If not, a deep cycle battery is a definite option.

JohnBFisher wrote: Sure, I have a generator. But I can not leave that running all night (or at least should not).

Why can't you leave the generator running all night? Just curious.

JohnNJ wrote:... Why can't you leave the generator running all night? Just curious. ...

It odds not safe to leave a motor unattended while you sleep. It is also very annoying for neighbours. For both reasons it is best to not run a generator all night.

JohnBFisher wrote:

JohnNJ wrote:... Why can't you leave the generator running all night? Just curious. ...

It odds not safe to leave a motor unattended while you sleep. It is also very annoying for neighbours. For both reasons it is best to not run a generator all night.

Thanks. I have a detached garage and in the times I have lost power I have kept the generator running non-stop for up to two weeks. The garage muffles the noise but there are many neighbors around me that run them outside. You can't really hear them with the windows closed. If I lived in a rural area I would invest in a natural gas or propane whole house generator but for the limited and infrequent times I've needed it I just use my portable gasoline generator.

YMMV