Forum Discussion
BFL13
Mar 10, 2014Explorer II
Homeless by Choice wrote:Bill.Satellite wrote:
All that really matters is the AH rating. You can go here to take a look at what you can run for what length of time. If you are drawing 100amps (not what a TV draws these days but might be a good combined usage number) you would be able to run 4.7 hours to complete discharge. However, you never want to do that and a 50% SOC is generally considered the correct time to recharge. That leaves you with only about 2.5 hours usage at that rate. Take another 5-10% loss due to inverter inefficiencies and you are down to about 2 hours.
http://ep.yimg.com/ty/cdn/sports-imports/BatterydrainCalc.html
Bill,
All I want to do is select a solar panel system that will fully charge my two batteries each day starting with 50% SOC. I don't have room for larger or more batteries. I will limit my usage to 50% SOC. I only need to run my CPAP machine each night. Any extra battery capacity is just a bonus.
I want this for a horizontal panel system for 66 degrees latitude on August 1st. If I can achieve that I will be very happy.
Thank you,
LeRoy
PS I am going to buy a watt meter tomorrow so I know what the CPAP uses. It's wattage is not labelled.
There have been several good threads about CPAPs if you can check them out. Several important aspects to them regarding battery draw running the CPAP different ways ISTR
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