Charge Controller w Vanner 24V Inverter

seamonkey
seamonkey Registered Users Posts: 9
  • two 17v panels connected to 2 12V batteries, both in series.
  • Vanner IT24 (volts) inverter, 3500 watts.
  • EP Solar Charge Controller , 12/24 volts.

I am starting with Solar for the first time and have a modest setup for my "office/garage." I would like to get this going and then expand to the whole house someday.


In any case, I am wondering if I have the wrong type of Charge Controller since the Vanner inverter is a monster. [HTML]IT24-3500 3500 120Vac +/- 5% 21-33.2Vdc +/- 5% 60 +/-.025Hz <4% THD* 75 lbs[/HTML] (3500 watts) and the charge controller seems to be cheapo ($50).

I want to get a more compatible Charge Controller but can't spend a lot. Any suggestions, thanks.

Thanks,
Dave

Comments

  • seamonkey
    seamonkey Registered Users Posts: 9
    Re: Charge Controller w Vanner 24V Inverter

    ALSO: Where can I find a good supply of Solar connectors wiring and components in San Diego? I can't seem to find anything.

    Thanks
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Charge Controller w Vanner 24V Inverter

    The type of charge controller is irrelevant to the inverter.
    Some basic system design rules of thumb:

    1). Determine potential loads. Both the maximum Wattage that will be used at any given time, and the total cumulative Watt hours for a day. These figures give you the information you need to size the inverter (maximum Wattage at any given time) and the battery bank (cumulative Wattage over a day).

    2). Once you got your battery bank sized, that determines how much solar panel you need to recharge it and what controller is needed to handle the job.

    The main problem with having too large of an inverter is that its standby or "idle" current could be using up more power than you need to expend. As in a 3500 Watt inverter consuming 25 Watts all the time just itself, whether there's anything else running or not. Eats into the battery bank capacity rapidly.

    Given that, if you've got figure on your panels' Wattage and your batteries Amp/hour capacity ("20 hour" rate) it is possible to determine approximately how much power you could expect to have available.

    I've never heard of an EP charge controller, so don't know the quality. Just because it's cheap doesn't mean it won't work. PWM type, perhaps?

    NOTE: There's lots of good reading in the FAQ section of this forum that will help you fill in the blanks on understanding this stuff! :Dhttp://forum.solar-electric.com/forumdisplay.php?f=14
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Charge Controller w Vanner 24V Inverter

    What's the wattage of each panel ? Do you have / can you post The sticker info from the backside Vmp, Voc, Iss, Imp ?

    If you don't have a lot of PV wattage, nearly any controller can manage it, but the question is, how efficient is it, will it harvest the power you have effectively ?
    Powerfab top of pole PV mount | 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-Lister ,

  • BB.
    BB. Super Moderators, Administrators Posts: 33,590 admin
    Re: Charge Controller w Vanner 24V Inverter

    It comes down to:
    • what are your loads (peak wattage, average wattage, watt*hours of daily operation)
    • what size (AH rating) and kind (flooded cell, AGM, etc.) of battery bank
    • how many solar panels do you have
    • do you have a backup AC charger
    This sort of gets into people usually under estimating their loads and over estimating the capabilities of the solar panels/battery bank.

    A 3,500 watt inverter is a good sized device--It would power my whole home pretty nicely.

    The solar charge controller is just one piece of the puzzle.

    My two cents--I probably would spring for more solar panels and a less expensive (but still good quality) PWM charge controller unless there was a very long wire run from the solar array to the charge controller.

    By the way, what kind of solar connectors are you looking for? MC4 type for solar panels, or something else?

    Usually, just purchasing some male/female MC4 jumper cables and cutting them in half to splice into the rest of your wiring system is the best deal. Proper crimp tools and getting a box of MC4 components is pretty expensive for a single home install. And it would be better to not cut off the MC4 connectors from the solar panels if you have other options.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • seamonkey
    seamonkey Registered Users Posts: 9
    Re: Charge Controller w Vanner 24V Inverter
    BB. wrote: »
    It comes down to:
    • what are your loads (peak wattage, average wattage, watt*hours of daily operation)
    • what size (AH rating) and kind (flooded cell, AGM, etc.) of battery bank
    • how many solar panels do you have
    • do you have a backup AC charger
    This sort of gets into people usually under estimating their loads and over estimating the capabilities of the solar panels/battery bank.

    A 3,500 watt inverter is a good sized device--It would power my whole home pretty nicely.

    The solar charge controller is just one piece of the puzzle.

    My two cents--I probably would spring for more solar panels and a less expensive (but still good quality) PWM charge controller unless there was a very long wire run from the solar array to the charge controller.

    By the way, what kind of solar connectors are you looking for? MC4 type for solar panels, or something else?

    Usually, just purchasing some male/female MC4 jumper cables and cutting them in half to splice into the rest of your wiring system is the best deal. Proper crimp tools and getting a box of MC4 components is pretty expensive for a single home install. And it would be better to not cut off the MC4 connectors from the solar panels if you have other options.



    -Bill

    Interesting that 3500 watts could run the whole house. I would love to power my whole home! From what I have been reading about this Vanner unit is that its intended for an RV. I guess I have to sit down and figure out my wattage demand.

    In any case, I am attaching the photos of the solar panels. They are not the same size. One puts out 45 watts and the other 50watts and nd 20 volts and 17 volts. Is this a big deal? In series the output has been 26 volts. (I have two 12V batteries in series)

    I know it would be best to have two exactly same panels but I am tight on money now.

    http://picasaweb.google.com/dhamra/Panels?authkey=Gv1sRgCMPGvvytj--QDA#5501364908345553938
  • BB.
    BB. Super Moderators, Administrators Posts: 33,590 admin
    Re: Charge Controller w Vanner 24V Inverter

    It is not a huge deal if the Imp currents are withing 10% of each other--if they are >10% difference--you can lose significant amounts of power due to the miss-match (the farther apart, the more power lost).

    However--your bigger issue is that you are talking about 100 watts of solar panels...

    Take 6 hours of "full sun equivalent" in very sunny summer weather. Assume flooded cell batteries and typical efficiencies for charge controller and inverter--Basically around 52% end to end efficiency.

    So, on a good day:
    • 6 hours of sun * 100 watts of panels * 0.52 = 312 Watt*Hours per day
    Your 3,500 watt inverter at full load will go through that amount of power in:
    • 312 watt*hours per day / 3,500 watt AC load = 0.09 hours or 5.3 minutes worth of power per day
    In the end, you have a little bit of solar panels and a whole huge inverter--Unless you only need 5 minutes of 3,500 watts a day--You probably are not getting what you expect/need from your system as configured.

    If you have daily blackouts (like some places around the world)--Adding a good quality battery charger and battery bank will allow you to operate a "large UPS" to keep your lights/appliances on during short outages.

    If you are looking for off-grid or emergency power to last you a couple weeks after an ice storm/hurricane--this setup is not ready for that demand.

    And, yes, it will take quite a bit of money to get something larger.

    If you need a few days/week or so of emergency power--then a good genset and fuel supply sized for your needs would be a better place to to invest some money (other than solar). Also, conservation for appliances to be powered in an emergency (energy star fridge/freezer, fuel based stove/heating/hot water if you have electric heat, one small room with a mini-split A/C or Heat Pump unit--rather than powering the whole home, etc.)...

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Charge Controller w Vanner 24V Inverter

    first of all the current passed will only be about that of the worst of the 2 pvs. what you posted was only for one of the pvs and it was not very readable from what i could see. anyway, you can think of what you have as a 90w pv setup. assuming you have about 100ah batteries then it becomes clear that you are low on the charge current as you should really at least double what you have to give the batteries a proper charge.
    also note that the inverter is most likely a modsine inverter and items that contain electric motors or coils are not recommended for use with that type of inverter and don't count on those 2 batteries delivering the full capacity of the inverter.
    where did you get the solarex pv?
  • seamonkey
    seamonkey Registered Users Posts: 9
    Re: Charge Controller w Vanner 24V Inverter
    mike90045 wrote: »
    What's the wattage of each panel ? Do you have / can you post The sticker info from the backside Vmp, Voc, Iss, Imp ?

    If you don't have a lot of PV wattage, nearly any controller can manage it, but the question is, how efficient is it, will it harvest the power you have effectively ?

    Here are the stickers on the back. Can is it okay to use these two different panels?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,590 admin
    Re: Charge Controller w Vanner 24V Inverter

    I could not see any pictures at that link.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • seamonkey
    seamonkey Registered Users Posts: 9
    Re: Charge Controller w Vanner 24V Inverter
    niel wrote: »
    first of all the current passed will only be about that of the worst of the 2 pvs. what you posted was only for one of the pvs and it was not very readable from what i could see. anyway, you can think of what you have as a 90w pv setup. assuming you have about 100ah batteries then it becomes clear that you are low on the charge current as you should really at least double what you have to give the batteries a proper charge.
    also note that the inverter is most likely a modsine inverter and items that contain electric motors or coils are not recommended for use with that type of inverter and don't count on those 2 batteries delivering the full capacity of the inverter.
    where did you get the solarex pv?

    Thanks.

    I got the solar panels off Craigslist at different times.

    Dave