New to forum, I am building my own camper and need help with panel and battery size, I am mounting 4 - 120 W panels at 480 Watts and 4 - 130 ah batteries at 520 ah, I am using a 30 A charge controller, my total power output is 1315 Watts with microwave, but only up to 10 minuets at 900 Watts, 7.5 A a day, most of the time only fridge will run at 180 Watts, 1.5 A, for maybe 5 hours we will watch TV, using laptop and maybe lights at 415 Watts, 3.5 Amps, will this work ? and maybe ball park to how long to charge batteries with full sun at 6 plus hours a day. Thanks, any help is good.
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Originally posted by Rick C View PostNew to forum, I am building my own camper and need help with panel and battery size, I am mounting 4 - 120 W panels at 480 Watts and 4 - 130 ah batteries at 520 ah, I am using a 30 A charge controller, my total power output is 1315 Watts with microwave, but only up to 10 minuets at 900 Watts, 7.5 A a day, most of the time only fridge will run at 180 Watts, 1.5 A, for maybe 5 hours we will watch TV, using laptop and maybe lights at 415 Watts, 3.5 Amps, will this work ? and maybe ball park to how long to charge batteries with full sun at 6 plus hours a day. Thanks, any help is good.
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IMHO,
480watts of PV will work for about 1200wh... in minimum 4 hour insolation.
However, an inverter will cut into efficiency and lower to 1000wh.
The 12v/520ah battery works well into that equation, but 4x parallel is not recommended.[CENTER]SunLight @ Night[/CENTER] -
Originally posted by Shockah View Post
Start Here
IMHO,
480watts of PV will work for about 1200wh... in minimum 4 hour insolation.
However, an inverter will cut into efficiency and lower to 1000wh.
The 12v/520ah battery works well into that equation, but 4x parallel is not recommended.Comment
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Originally posted by Rick C View PostTHANK YOU for the fast help, but I am not Shure what you mean by parallel, Pos to Pos, Neg to Neg makes 12V, Pos to Neg makes 12 X 4 = 48V, Right ?
Pos to Pos, Neg to Neg makes 12V = Parallel.
Pos to Neg makes 12 X 4 = 48V = Series.
Series draws current from batteries equally... better for longer life.
What is the input voltage of your inverter?
FYI:
(4) 12v/130ah in series = 48v/130ah
(4) 12v/130ah in parallel = 12v/520ah[CENTER]SunLight @ Night[/CENTER]Comment
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Fist two huge expensive mistakes you are doing is using 12 volt battery panels and a PWM controller. It is a waste of money and energy. You can use two grid tied panels of 240 watts each at 1/2 the cost with a 40 amp MPPT controller. Total cost will be less than 4 battery panels and PWM controller. That is the money part. For the energy part It only takes a 330 watt MPPT system to equal a 480 watt PWM system. Or a 720 watt PWM system to equal a 480 watt MPPT system.
Next mistake is using 4 12 volt batteries in parallel. If you need 520 AH @ 12 volts then use either 4 or 6 volt 520 AH batteries wired in series.
Last point is you are going to need a generator, or a battery isolator for the vehicle alternator to do most of the charging for you.MSEE, PEComment
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Originally posted by Shockah View PostCorrect.
Pos to Pos, Neg to Neg makes 12V = Parallel.
Pos to Neg makes 12 X 4 = 48V = Series.
Series draws current from batteries equally... better for longer life.
What is the input voltage of your inverter?
FYI:
(4) 12v/130ah in series = 48v/130ah
(4) 12v/130ah in parallel = 12v/520ahComment
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Originally posted by Sunking View PostFist two huge expensive mistakes you are doing is using 12 volt battery panels and a PWM controller.
Rick said 30amp, I assumed MPPT you assumed PWM... I'm not putting any money on my assumption[CENTER]SunLight @ Night[/CENTER]Comment
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Originally posted by Rick C View PostInverter is 2500 Watt Power Drive, 12V input, I guess I forgot to include that, I'm a retired truck driver and buy a lot of my stuff at truck stops.
Start again.
See Sunking's post above and use Off-Grid Calculator.[CENTER]SunLight @ Night[/CENTER]Comment
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Originally posted by Shockah View PostI didn't catch it was a PWM CC...?
Rick said 30amp, I assumed MPPT you assumed PWM... I'm not putting any money on my assumptionMSEE, PEComment
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Originally posted by Rick C View PostInverter is 2500 Watt Power Drive, 12V input, I guess I forgot to include that, I'm a retired truck driver and buy a lot of my stuff at truck stops.MSEE, PEComment
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I am building this camper on the back of my pickup truck, I already have inverter and batteries, the pocket I built for batteries is 14 X 10 X 30, I have room for four Batteries and no more, panels, I can do something else. I don't know the deference in inverters, I had this inverter in my semi truck and ran off the truck batteries, like I said, I am a truck driver and only thing I know about 12V power is what I learned from other truck drivers, and that's not much, HA HA.Comment
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Originally posted by Rick C View Post.......I am a truck driver and only thing I know about 12V power is what I learned from other truck drivers, and that's not much, HA HA.
Read the link about system size and the Off Grid Calculator.Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-ListerComment
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Originally posted by Mike90250 View PostWe will educate you. Stop building anything. You are going to have to make a HUGE shift from Truck with nearly unlimited power, to your camper, with a 100A alternator. Every watt you can save makes a big difference. Solar will never be aimed right, and therefor, you should only expect about 1/2 the nameplate power from the PV. Huge battery bank only means huge expense to replace it in a year when it dies.
Read the link about system size and the Off Grid Calculator.Comment
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Originally posted by Rick C View PostI don't know what link you are talking about ? if its the one earlier in this thread it won't open, ......
It is an excel spreadsheet compressed into a "zip" file.
Bottom line is you have a poor match of components.
It would be similar to putting your pick-up truck engine in your 18 wheeler and expecting to haul a full load cross-country.
Firstly, sell the 2500watt inverter to another trucker.
Another great link for you >>> http://www.solarpaneltalk.com/showth...-Size-Tutorial[CENTER]SunLight @ Night[/CENTER]Comment
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I agree with much of what was said to you and being you have the batteries already then try to get a 24 volt or 48 volt inverter to better utilize them. You mention you bought them a year ago so how did you maintain them for that year? If they weren't properly cared for you may be replacing these soon too.Comment
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