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High Quality Solar Generator Advice Please

CircuitsActivated

CircuitsActivated

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Virginia, USA
Hello everyone. I would like your advice as I have now learned my lesson. I did my research and on paper what should have worked did not work in reality. I use a CPAP machine every night. A main goal in purchasing a portable solar generator was for powering the cpap in a tent camping or power outage situation. I bought a Rockpals 300 and guess what, the 12 volt DC circuit goes in to protection mode and will not run the cpap at all. The specs say it will but reality says different. My NAPA Carlyle automotive jump starter box will run the cpap, but that has an AGM battery in it and is made for high current draw to start a car. The 12 volt port inside it is unregulated and simply connected directly to the AGM battery and is live all the time. I am working with Rockpals to return the 300 solar generator.
I would like your advice please. I can use the online chart from ResMed to get a ball park draw figure for DC and I can use my Kilowatt to get a figure for AC. I have been bitten by the poor quality control bug of the low quality market. Which brans make high quality products that you can depend on? Which brands have high quality control? I understand I may pay more, but I would rather pay a few dollars more for high quality than to deal with “I hope this will work” again. Thank you for your help.
 

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Rockpals uses lipo to power the outlet, so it is starting off with only 12.6V max, around 11.1 typical... you need one of the newer LiFePO4 units with a regulated 13.8V output.
I saw a review for one recently, and it had 500WH, regulated 13.8 output, and around 500$ price

Will hasn’t reviewed it yet, but this review looks pretty fair.
 
Of course, DIY will be bigger, better, and less expensive if you can follow some decent instructions.
 
And, since you have that blue jump box, you could open it up, and slap in a 20ish Ah LiFePO4 replacement battery for around $90 and get a cheap diy...
 
Thank you for the reply. I am new to this sort of thing. I am not against the DIY route but my question is realistically how much savings are we talking about? I hold general tools such as automotive mechanics tools, Weller soldering gun and iron, Klein multimeter, etc. My main demands would be for DC current devices but my main goal is powering the CPAP. If I need to power a coffee pit, toaster, electric skillet, etc I can use a small inverter gas generator for that. Will I save money going DIY over the $500 unit in the video or the $500 Jackery 500? I have looked at a few Youtube videos about the DIY solution but many use a $1000 battery, an AGM battery that weights 75 pounds, or build a custom pack from 18650 cells. I am less interested in this being a hobby and more interested in a device that I can depend on, that is reliable, and will work when needed. If you can help me design a DIY system (I am a newbie) then I am game. Thank you for the reply and help.
 
Supervstech said:
And, since you have that blue jump box, you could open it up, and slap in a 20ish Ah LiFePO4 replacement battery for around $90 and get a cheap diy...
Click to expand...
Sorry to keep being a bother but I have another question. Would not a dc-dc converter work for giving me a regulated 12 volt supply for the Rockpals or the automotive jump box? This would avoid returns to Rockpals, recredit to my debt card, plus use what I already have. Thank you for your input.

 
Yes, that will work. I would just get one designed for 13V regulation though.
The adjustable ones need tools to measure output points. Several boost 13V regulators out there.
But if you can return the rockpals, I would.
Plenty of lower cost options out there much better than the RP300
The 22Ah LiFePO4 drop in battery would upgrade the jump box to a 281Wh 12.8V supply with thousands of recharge lifetimes...
www.ebay.com

10AH 20AH 30AH 50AH 12V Deep Cycle Lithium Battery LiFePO4 for RV Boat Solar Kit | eBay

200W Solar Panel Kit & 2 20AH. 48V 50AH Lithium Battery. System & 2 48V 50AH Lithium. System & 3 48V 50AH Lithium. System & 4 48V 50AH Lithium. LiFePO4 Battery. Solar Panel Kit. Solar Battery System.
www.ebay.com
Something along these lines should drop into your box.
 
Hey Circuits Activated - I'm a Respiratory Therapist. I have a lot of experience with PAPs on the DME side and working with soldiers from Fort Drum.
First to give you a ball park ideal with LiFePO4 batteries, that would be the way to go. First you really need to take a look at your needs - are we looking for when the power goes out overnight; tenting on a Friday/Saturday night; off grid cabin for a week; etc.? This will help determine the battery size. I have a Jackery 300 and love it. Now if we run a CPAP thru the AC inverter on it, it averages 37 watts/hr. If you use that for 8 hrs a night x 37 watts/hr + 296 wh used. So that will last one night. This is based on the heated humidifier being off and using the humidifier has a passive humidifier. I'm only using Jackery as an example, IMO I think they make a rock solid product. So figure with Jackery its about a $1.00/wh (watt hour). So if you get the Jackery 1000 for $999.99 that would give you approx. 27 hrs of CPAP use.

I think I'll do a build on this and post online:

Ampere Time 12V 100Ah 1.28KWh Lithium|LiFePO4| 499.99​

BESTEK 500W Pure Sine Wave Power Inverter 60.99​

Linkstyle Cigarette Lighter Power Plug Dual Socket, 7.99​

NOCO Genius G15000 12V/24V 15 Amp 177.64​

T Tocas 100 Amp Circuit Breaker with Manual Reset, 27.99​

Total would be $ 774.60 for the parts. As far as tools and wire you might even have those and if not, can get that at the BORG for <$50.00.

This would give you about 34 hours of CPAP use. AND its easy to upscale - larger battery, more batteries, etc.
 
efmrrt said:
Hey Circuits Activated - I'm a Respiratory Therapist. I have a lot of experience with PAPs on the DME side and working with soldiers from Fort Drum.
First to give you a ball park ideal with LiFePO4 batteries, that would be the way to go. First you really need to take a look at your needs - are we looking for when the power goes out overnight; tenting on a Friday/Saturday night; off grid cabin for a week; etc.? This will help determine the battery size. I have a Jackery 300 and love it. Now if we run a CPAP thru the AC inverter on it, it averages 37 watts/hr. If you use that for 8 hrs a night x 37 watts/hr + 296 wh used. So that will last one night. This is based on the heated humidifier being off and using the humidifier has a passive humidifier. I'm only using Jackery as an example, IMO I think they make a rock solid product. So figure with Jackery its about a $1.00/wh (watt hour). So if you get the Jackery 1000 for $999.99 that would give you approx. 27 hrs of CPAP use.

I think I'll do a build on this and post online:

Ampere Time 12V 100Ah 1.28KWh Lithium|LiFePO4| 499.99​

BESTEK 500W Pure Sine Wave Power Inverter 60.99​

Linkstyle Cigarette Lighter Power Plug Dual Socket, 7.99​

NOCO Genius G15000 12V/24V 15 Amp 177.64​

T Tocas 100 Amp Circuit Breaker with Manual Reset, 27.99​

Total would be $ 774.60 for the parts. As far as tools and wire you might even have those and if not, can get that at the BORG for <$50.00.

This would give you about 34 hours of CPAP use. AND its easy to upscale - larger battery, more batteries, etc.
Click to expand...
Yup, that would be great, it looks like he just uses the 12V setup, so it just needs reliable 12V output.
Running the 120V connection would work with the RP300 he has overnight.
 
Supervstech said:
Yup, that would be great, it looks like he just uses the 12V setup, so it just needs reliable 12V output.
Running the 120V connection would work with the RP300 he has overnight.
Click to expand...
Thank you both very much. You are right, I could just use the Rockpals I have via the 120 volt inverter. Once my Kilowarr gets here via the big brown truck, I will see how much power it uses over a few nights. The entire reson I am interested in powering the ResMed S10 auto cpap via 12 volts is due to the losses of converting the 120v AC to 12 volt DC using the Rockpals. In my mind I thought it would run longer on the 12 volt input. If the cpap will run for one nights sleep and then recharge for another nights sleep....then I can just keep what I have. I bought the Rockpals for $190 (Jackery was $300) and with the watt hours it has and using the cpap chart from ResMeds....I thought the numbers worked out fir my use. What I do not know as of right now is how much wattage the cpap actually uses. That is why I have a Kilowatt on the way. I want to thank you both for this help. I did not mention this before, but I am legally blind. Not black blind but very near sited, can not drive, etc. I mention it because that too is why I was looking for a pre-made all in one solution. I know I can use the display on the Rockpals to get an idea of the load applied with the cpap, but I do not know if that number will change once I am sleeping. On another note, I have the security bit to remove the screws from the automotive jump box, but the shaft of the handle is too large to provide reach. I will work on that but it is still funny. Yep my main goal with the Rockpals 300 is to power the cpap if the grid electricity goes out. The other use for the Rockpals would be to charge an iPhone, iPad, run a USB lightbulb, light duty stuff if the power goes out. I live in the country on a small farm so I can run the small gas generator without disturbing anyone if I needed to make coffee ir cook an egg. Thank you both for the help.
 
I have a different version RP300, and it has a solar input port on the back, that when attached to a car battery, will keep the pack above 12V...
It might be an option for additional runtime if yours has the feature.
 
Does the rock pals charge from 12 volt? Can it output power while charging? What happens if you plug the rock pals into the jump pack?
 
Supervstech said:
Like minds...
Click to expand...
;) I should have read the thread to the end. :mad:

I have a jump box I was using with a small inverter to keep my cordless phone going before I built my battery backup. I connected the jumper cables to a second 12 volt battery to extend the run time.
 
Alright everyone. The Rockpals 300 will not power the cpap from its 12 volt DC. It goes in to protect mode. The jump box will charge the Rockpals. However, when charging the Rockpals the DC stays active and it turns off the 120 volt inverter. This is getting fun.
 

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Can the rockpals keep the jump box charged?

I know it would be better to have one box to run the CPAP, but it's also nice to know what can get you out of trouble if you have to improvise.
 
Shoot, my R300 has a dedicated mppt input on the back that will charge while running the 120. I guess your model is different.
Are you sure there isn't a solar input port on the back?
 
Is that an actual Resmed 12/24 volt power converter? To me it looks like generic adaptor. The Resmed power converter on 12 volts uses 13 amps. I doubt the Rockpals will let you go above 10-12 amps. Most likely that's the issue. Also the higher the pressure = more power consumed. I based my numbers on a CPAP of 10 cmH2O (average is 9-13 cmH2O).

The Rockpals won't tell you the amount of watts used?

Resmed technical specifications 90W power supply unit AC input range: 100–240V, 50–60Hz 1.0–1.5A, DC output: 24V 3.75A Typical power consumption: 53W (57VA) Peak power consumption: 104W (108VA)

WOW! That's almost double of the Respironics Dreamstation.

So based on the 53 watts with the Rockpals your going to have about 5 1/2 hrs a night out of it. You'd be better off buying a CPAP battery for about $150.00 which would give you about 10-14 hrs run time.
 
Q-Dog said:
Can the rockpals keep the jump box charged?

I know it would be better to have one box to run the CPAP, but it's also nice to know what can get you out of trouble if you have to improvise.
Click to expand...
The jump box charges with its included external automotive 12 volt 2 amp charger. It has a plug on the end of its cable to connect it to the jump box. In theory the Rockpals could charge the jump box from its 120 volt port but charging a battery from a battery does not seem like a worthwhile idea. The 12 volt cigarette plug in the jump box is not regulated and is live all the time. The manual says the plug is 12 volts 15 amps and is connected directly to the battery. That is 180 watts. Could you not use a solar panel and an inexpensive pwm ir mppt charge controller to charge the battery in the jump box? How could you keep from draining its AGM battery below 50% to prevent damage to it from a night on the cpap? I am trying to figure out what battery is inside the jump box...its specs. I have the right security bit to open it but the screwdriver shaft is too large for the recessed holes. The manual gives a battery part number for replacement but I find nothing. I was hoping that would provide the battery specs. I am enjoying the puzzle.The part number given in the manual is 5799000047Z. The given specs in the manual are as follows:
CJP400
Internal battery type ....................................................Maintenance-free AGM lead-acid Nominal voltage ..................................................................................................12V DC DC power outlet (max. continuous load)................................................................... 15A Peak amps .............................................................................................................. 2000 Cranking amps.......................................................................................................... 400 Jumper cables.................................................................................... 4 AWG, 30 Inches Dimensions – W x D x H (inches) .....................................................12.01 x 5.52 x 9.45 Weight....................................................................................................18.5 lbs (8.5 kg)
 
CircuitsActivated said:
The jump box charges with its included external automotive 12 volt 2 amp charger. It has a plug on the end of its cable to connect it to the jump box. In theory the Rockpals could charge the jump box from its 120 volt port but charging a battery from a battery does not seem like a worthwhile idea. The 12 volt cigarette plug in the jump box is not regulated and is live all the time. The manual says the plug is 12 volts 15 amps and is connected directly to the battery. That is 180 watts. Could you not use a solar panel and an inexpensive pwm ir mppt charge controller to charge the battery in the jump box? How could you keep from draining its AGM battery below 50% to prevent damage to it from a night on the cpap? I am trying to figure out what battery is inside the jump box...its specs. I have the right security bit to open it but the screwdriver shaft is too large for the recessed holes. The manual gives a battery part number for replacement but I find nothing. I was hoping that would provide the battery specs. I am enjoying the puzzle.The part number given in the manual is 5799000047Z. The given specs in the manual are as follows:
CJP400
Internal battery type ....................................................Maintenance-free AGM lead-acid Nominal voltage ..................................................................................................12V DC DC power outlet (max. continuous load)................................................................... 15A Peak amps .............................................................................................................. 2000 Cranking amps.......................................................................................................... 400 Jumper cables.................................................................................... 4 AWG, 30 Inches Dimensions – W x D x H (inches) .....................................................12.01 x 5.52 x 9.45 Weight....................................................................................................18.5 lbs (8.5 kg)
Click to expand...
I looked on the NAPA website unfortunately there is nothing about amp hours which makes this hard to figure. With the money spent on the 2 devices ($188 Jump pack and 250 for Rockpals) a Jackery 500 at 449.99 would be the best route and grab a 100 watt solar panel. Although Jackery is unveiling a new battery pack on March 17 and goes on sale on March 18. They may have some great deals on the small or older models.

We are just trying to get you thru the night on CPAP. As far as charging batteries (cell phone, etc) and running a 5 watt USB light you'll be SOL.
 
efmrrt said:
Is that an actual Resmed 12/24 volt power converter? To me it looks like generic adaptor. The Resmed power converter on 12 volts uses 13 amps. I doubt the Rockpals will let you go above 10-12 amps. Most likely that's the issue. Also the higher the pressure = more power consumed. I based my numbers on a CPAP of 10 cmH2O (average is 9-13 cmH2O).

The Rockpals won't tell you the amount of watts used?

Resmed technical specifications 90W power supply unit AC input range: 100–240V, 50–60Hz 1.0–1.5A, DC output: 24V 3.75A Typical power consumption: 53W (57VA) Peak power consumption: 104W (108VA)

WOW! That's almost double of the Respironics Dreamstation.

So based on the 53 watts with the Rockpals your going to have about 5 1/2 hrs a night out of it. You'd be better off buying a CPAP battery for about $150.00 which would give you about 10-14 hrs run time.
Click to expand...
Just for giggles I wore my ResMed S10 auto cpap for ten minutes. It was plugged into the Rockpals 120 volt outlet. The wattage shown was 20 on inhale and 16-18 exhale. If those numbers are accurate then an eight hour sleep is 160 watts and ten hours is 200 watts. That means the Rockpals would run the cpap for one night then need a solar charge in a power outage. To answer your other question, that 12 volt cpap adapter is also from Rockpals, it is not a ResMed adapter. The NAPA jump box will power the cpap with that Rockpals adapter. Oddly enough the Rockpals 300 will not piwer the cpap with its own adapter.
 

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efmrrt said:
I looked on the NAPA website unfortunately there is nothing about amp hours which makes this hard to figure. With the money spent on the 2 devices ($188 Jump pack and 250 for Rockpals) a Jackery 500 at 449.99 would be the best route and grab a 100 watt solar panel. Although Jackery is unveiling a new battery pack on March 17 and goes on sale on March 18. They may have some great deals on the small or older models.

We are just trying to get you thru the night on CPAP. As far as charging batteries (cell phone, etc) and running a 5 watt USB light you'll be SOL.
Click to expand...
Yeah the NAPA jump box was a gift a while back and was on sale for $110 at the time. It is nice to keep in the truck and charged should it ever be needed. It has come in handy and saved a few people with dead batteries at Walmart or Tractor Supply. I did not buy the jump box. I did buy the Rockpal 300 for $190 with coupon code.

While doing some more looking I found the name brand unit to my jump box. My NAPA jump boxed was made by Schumacher and rebranded for NAPA. Looking up the battery for the unit I find that what is inside is a 12 volt 22AH AGM battery. That gives me 264 watt hours. However, if I am learning anything, this is an AGM battery thus meaning it is not a good idea to drain it below 50%. That means 132 watt hours useable. At the 20 watt load I saw from the cpap connected to the Rockpals, that gives me roughly 6.6 hours of sleep using the 50% drain rule. I guess that in an emergency situation you could go past that limit a few times. I could also at some point put a 22AH LiFePo4 battery in the jump box.
 
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