Power Inverter and Oxygen Concentrator

I am hoping that the experience on this forum can provide me some guidance on whether or not it is a good idea to install a power inverter to power my mom’s oxygen concentrator in her vehicle (2010 Lexus RX350). Not a 4Runner I know...but hopefully nobody will fault me for that. She has bad lung disease and requires oxygen at all times. She has a small battery powered unit that she uses when she travels but her demands are about to exceed what this unit can put out and there are no “portable” units that provide more flow than what she currently is using.

For those of you with friends/family that require oxygen you know it is a huge PITA and can lead to a significant impact on lifestyle. In hopes of helping my mom maintain as much freedom as possible with her current setup I was curious about installing a home oxygen unit (runs off 120V) with a power inverter in the back of her car.

I know there are plenty of inverters that would supply enough power for its use but not sure if there are other considerations that would make this a bad idea…she would always travel with a back-up supply (already does) but this needs to be bullet proof…

Here are the specs on the Home Oxygen Unit that I would install:
Invacare Platinum 10
Electrical Requirements: 120 VAC +/- 10% (132 VAC/108 VAC), 60Hz
Rated Current input: 4.7 A

I have read a number of threads on this forum (and others) regarding power inverters and oxygen concentrators and they have been very informative but I wanted to reach out to the electrical engineers/gurus or others on T4R.org that may have tried to do this to see if they have any thoughts/recommendations? Is this a bad idea? I would think this can be done and done safely but want to be sure.

For my mom, the alternative to oxygen concentrators is switching to liquid oxygen and that is a completely different setup and they are not mix and match.

Questions:
1) What size inverter and type would be best? (There is no comment about amount of energy surge on start-up and it is unlikely my folks will use the inverter to power anything else at the same time.)
--1000W reasonable?
2) What specifications should her car battery meet?
3) Do I need to worry about the alternator keeping up with the continuous energy drain? (Motor would always be running except for refueling and think it has a 150Amp alternator)
4) Other considerations?

Thanks guys, this makes me nervous…appreciate any help you can offer.

I'd keep the inverter to about 25% above requirements. So you got 120v and 4.7 amps, that equals 564 watts needed, so shoot for about 700 to allow for some headroom on the inverter.

Obviously make certain the battery is in 'newish' condition (perhaps test it).

I'd shoot for an inverter that has a cooling fan for the extended use you have in mind. I also wonder, what if her car breaks down, how much time does her 02 generator have before it conks out and how much time does that leave her, meaning what is Plan B? Luck.

Thanks for the info jgue467.

Plan B: She caries multiple D-tanks within arms reach that provide adequate flow for back-up situations. They provide multiple hours of back-up which is sufficient for now.

OK, don't worry, this is a simple thing and you'll help her out easily.

First of all for it to be bulletproof you want to make sure you use a high quality inverter, no swapmeet specials.

Second, it is NOT a bad idea, it is a very good and simple solution to a problem.

Now your questions (1) 1000W is probably overkill, based on the specs you need 300W continuous, if you account for inefficiency and fudge factors you could easily get away with 600W.
(2) At this level, she doesn't need to change or add a battery. If you think she'll use it with the vehicle not running for more than a few minutes then you'd have to seriously consider a 2nd battery that was properly isolated.
(3) The alternator will have no problem, the amperage draw will be in the 25-30 Amp range depending on efficiency. You should evaluate the heavy gauge wire between the Alternator and your battery, you may want to upgrade it ala the "Big 3" 3rd gen upgrade. Many modern cars return the charge through the Main fuse block, be sure all the connections are good, clean and capable of what they are rated for.
(4)The other consideration is how you build the system. The more wattage inverter you use, the larger cable required. The larger cable you use the harder it is to crimp ends and bend around corners. There are lots of write ups here where people have installed inverters, and you will find all kinds of different ideas. You should stick to a forum or info source more related to RV or Inverter topics. Google is your friend!

My idea, Use a 600W inverter, 2G or 0G cable to the battery. Add a 2G cable between the Alternator and the Battery with a 100A circuit breaker in line. Remember, go with the best quality available.

Have fun with the project!

Papabeach, I don't know how sensitive the oxygen unit is to current fluctuations. just be careful and use a sine wave inverter or check with the manufacture of the unit to see what would be acceptable as not to cause any damage to the unit itself. May not be an issue but better safe than sorry. Ray.

That's way low. This will draw 47 amps with a 12V input if the inverter is 100% efficient. In the real world the current draw from the vehicle is going to be more like 55-57 amps, and it's probably pushing it a little for the stock electrical system if this things is running constantly.

You wouldn't be able to run it long at all with the vehicle off before you risk not being able to start it again.

My bad, I stand corrected! The draw WILL be 47 Amps. Not sure how I even came up with 284W.(I blame it on the two year old's birthday party I hosted yesterday) It's actually 564, which would need a larger inverter than I originally said. More like 800-1000 to be safe. You'd have to keep it running, for sure, at that draw the battery would be dead in an hour. Thanks for catching that fail jeremy

Appreciate the help fellas...looking at Powerbright 1000W pure sine inverter...seems like good price with some good reviews. I will let ya'll know how it goes if she agrees to go this route. Amazon.com: Power Bright APS1000-12 Pure Sine Power Inverter 1000 Watt continuous / 2000 watt Peak 12 Volt DC To 120 Volt AC: Patio, Lawn & Garden

Converting the 12vdc amps to the 120vac amps is 10:1. For every 1a of 120VAC there will be 10a of 12VDC needed