possible starter system

24

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: possible starter system

    Running the trailer's converter is probably correct.

    A small battery system to run lights, laptop, cell charger, etc. and use a small generator and or solar panels.

    Use a genset for larger loads. The Honda eu family are very nice for these smaller loads.


    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: possible starter system

    And don't disconnect the batteries from the converter.

    And the converter load is probably too small to worry about with the generator.

    Of this was a load on an inverter battery system, it would be a different issue.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system

    So I know I have learned a lot in the last year, but I also know I am still way down at the beginning of the learning curve. One thing I haven't figured out yet is why would you want to have four 135W panels instead of two or three 200 - 240W panels? They don't seem to be that much cheaper and you're taking up valuable real estate on top of an RV with more panels of a lesser power. There's probably an obvious answer, but it just hasn't hit me yet.
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: possible starter system

    A series of Internet Factoids:
    • Roughly, 135 watt and smaller panels can be cheaper to ship (large panels need to go by truck).
    • At this point, Kyocera ~135 watt panels are among the last that are still being built with Vmp~17.5 volts--This allows these panels to be used with cheaper PWM controllers on 12 volt battery banks (and 24/48 volt banks).
    • 175 Watt panels are about the largest that can be moved around by one person without help.
    • Smaller panels may let people better fit them to the roof profile/footprint.
    • Larger wattage panels usually require MPPT controllers which cost a lot more--But these days are usually better controllers with more features (upgradeable firmware, computer interfaces, some even have Internet servers, etc.).
    • Larger panels need less wiring connections (a good thing).
    • Larger panels are typically used for high volume grid tied applications--So they can be much less $$$/watt pricing.

    So, look at your needs and figure out which will meet your requirements at the best price.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system

    Good enough. Thank you!
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system
    BoFuller wrote: »
    OK, fine,

    4 - 200-240W panels - to be mounted flat on the roof of the travel trailer
    A Xantrex MPPT60 charge controller
    4 Trojan T-105 batteries
    A Xantrex TR2412 inverter/charger
    and a TriMetric battery meter

    Thanks!

    What's the determining factor when deciding whether to go 12V or 24?
    Distance is not a problem here. I can put everything very close to the trailer.

    I'm thinking I want to change to 24V now. An updated list would be;

    4-6 Kyocera KD235GX panels
    Morningstar Tristar 60 amp MPPT charge controller
    4 Trojan T-105 batteries - which I won't order until later
    Outback FX2524T inverter
    TriMetric meter - already ordered

    Any comments on the choices before I pull the trigger and order?

    Then I'm thinking a 6" pole for my pole mount with a top-mounted rack.
    Probably 6' in the ground and 8' out.
    I'll use the directions from "How to install a pole-mounted array" from Homepower magazine.

    Comments and suggestions welcome.
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system

    And what about a combiner? I was looking at something like the MidNite Solar MNPV4-MC4 Solar Array Combiner. Not being an electrician, I sort of like the pre-assembled boxes. But since I might use 6 panels, I guess I would need the MNPV8-MC4 instead?
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: possible starter system
    BoFuller wrote: »
    Then I'm thinking a 6" pole for my pole mount with a top-mounted rack.
    Probably 6' in the ground and 8' out.
    I'll use the directions from "How to install a pole-mounted array" from Homepower magazine.

    Well, that's a big change from 4 panels on the roof of your trailer. If you are in snow country I would advise you to find a pole mount that allows you to put your panels in a vertical position when there is snow on the ground.
    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • NoGrid
    NoGrid Registered Users Posts: 12
    Re: possible starter system

    Interesting thread as I am researching to do similar project. I would have to say that other than the converter/charger there is also the CO and propane detectors, TV, stereo, microwave clock, etc that cause a phantom (or vampire) load that can not be easily turned off.
    I do have a few questions though:
    Do you plan on keeping the converter/charger in circuit? I was going to disconnect mine and run a seperate cable for the 12V loads. Too many losses in capturing 12V, converting to 120VAC and converting back to 12V and then you are using a battery to charge a battery. The only heavy 12V loads are the furnace fan and water pump.
    Are you seriously thinking of installing a wood burning stove in your camper? Do they make "camper save" models? Seems hazardous in many ways.

    By the way, your wife is demanding just the microwave. Mine wants A/C as well :(
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: possible starter system

    You can buy CO detectors from the hardware store that use a pair of AA batteries every year...

    However, if you are looking at A/C--I would not sweat the small stuff.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system
    NoGrid wrote: »
    Interesting thread as I am researching to do similar project. I would have to say that other than the converter/charger there is also the CO and propane detectors, TV, stereo, microwave clock, etc that cause a phantom (or vampire) load that can not be easily turned off.
    I do have a few questions though:
    Do you plan on keeping the converter/charger in circuit? I was going to disconnect mine and run a seperate cable for the 12V loads. Too many losses in capturing 12V, converting to 120VAC and converting back to 12V and then you are using a battery to charge a battery. The only heavy 12V loads are the furnace fan and water pump.
    Are you seriously thinking of installing a wood burning stove in your camper? Do they make "camper save" models? Seems hazardous in many ways.

    By the way, your wife is demanding just the microwave. Mine wants A/C as well :(

    Actually she would be willing to give up the microwave.
    For heat, a friend of mine put a small wood burning stove in his. I'll have to ask him more about it.
    Setting up all the solar system doesn't seem that hard, but what has me puzzled is how and what to bypass inside the trailer. Do I just plug my landline plug into the solar system? Or do I locate a technical manual and find out where everything is in the trailer and take it out and sort of rewire? Everything appears to be behind existing panels, so I don't really know what I am looking for or where I am to look.
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system
    BB. wrote: »
    You can buy CO detectors from the hardware store that use a pair of AA batteries every year...

    However, if you are looking at A/C--I would not sweat the small stuff.

    -Bill

    If I want A/C for the few days it is hot enough, I will hook up the generator.
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • NoGrid
    NoGrid Registered Users Posts: 12
    Re: possible starter system
    BoFuller wrote: »
    Actually she would be willing to give up the microwave.
    For heat, a friend of mine put a small wood burning stove in his. I'll have to ask him more about it.
    Setting up all the solar system doesn't seem that hard, but what has me puzzled is how and what to bypass inside the trailer. Do I just plug my landline plug into the solar system? Or do I locate a technical manual and find out where everything is in the trailer and take it out and sort of rewire? Everything appears to be behind existing panels, so I don't really know what I am looking for or where I am to look.

    All the wiring goes to the breaker/fuse panel. The converter/charger should be located behind this panel usually located lower left. it's a metal box. One thing I do to reduce the parasite's while camping on battery (boondocking) is turn off the breaker feeding the microwave, pull the fuse feeding the radio and unplug the TV/sat when not in use. There are no manuals and each camper is wired differently so you will have to determine what breaker/fuse goes to what by pulling a fuse, determine what doesn't work and label it.

    My idea at the moment is isolate the 120AC system from the 12VDC by opening the breaker feeding the converter, plug the camper into the inverter via a pedestal connection like you find in the campground and cunnect one of the 12V batt's in the batt string to the house battery connection at the tounge. Disconnect the house battery. It would be cleaner to make the 12V connection in the breaker panel at the converter output but I don't want to drill a hole in my floor. I'm sure someone here will point out the down side of having an additional load on one battery in a string. I could move this connection from battery to battery if it protects the health of the batteries.

    BB's A/C comment was directed towards me

    On Edit: another thing to consider in a camper is lighting. The miser approach is changing to LED lights. Each standard bulb is 18W. If you have the type of light fixture that turns on both lights at once, remove one of the bulbs to cut that draw in half. My previous camper had the three way switch that allowed me to turn on just one light wheras my new does not. It's either both lights on or none.
  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system
    BoFuller wrote: »
    I'm thinking I want to change to 24V now. An updated list would be;

    6 Kyocera KD235GX panels
    Morningstar Tristar 60 amp MPPT charge controller
    4 Trojan T-105 batteries - which I won't order until later
    Outback FX2524T inverter
    TriMetric meter - already ordered

    Any comments on the choices before I pull the trigger and order?

    Comments and suggestions welcome.

    Not trying to beat a dead horse here, but I'm a little nervous about putting out the cash and finding there was a better combination.
    Any problems with this combination?
    Thanks, Bo
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: possible starter system

    Battery bank size??? Seems a bit small for the panels and inverter you have (if you intend to use "full power")...

    A Nominal system based on your solar array would look something like:
    • 6x 235 watt panels * 0.77 * 1/29 volts charging * 1/0.05 rate of charge = 748 AH @ 24 volts Maximum sized battery bank
    • 6x 235 watt panels * 0.77 * 1/29 volts charging * 1/0.10 rate of charge = 374 AH @ 24 volts "Nominal" sized battery bank
    • 6x 235 watt panels * 0.77 * 1/29 volts charging * 1/0.13 rate of charge = 288 AH @ 24 volts "Small" sized battery bank

    Your current battery bank is only ~225 AH @ 24 volts... You could go larger if you wished.

    And, assuming you run the battery bank at a maximum rate of discharge of C/8 (for flooded cell), the above banks would supply (through your AC inverter):
    • 288 AH * 24 volts * 0.85 eff * 1/8 rate of discharge = 734 watts for "small bank"
    • 374 AH * 24 volts * 0.85 eff * 1/8 rate of discharge = 955 watts for "nominal bank"
    • 748 AH * 24 volts * 0.85 eff * 1/8 rate of discharge = 1,909 watts for "large bank"
    • 225 AH * 24 volts * 0.85 eff * 1/8 rate of discharge = 574 watts for "your bank"

    Note the above supported AC Wattage would be about 2x for starting surges.

    Personally, I do like largish solar arrays--Very nice to get your system quickly recharged the next day... Also, if you have a lot of "daylight loads" (say well pumping, shop, fans, etc.), You can get away with a smaller battery bank if much of your power is used during the middle of the day.

    Also, what are your primary/backup power plans (AC Utility/Generator)?

    Your thoughts?

    -Bill

    I am sure you said your usage two or three pages earlier in the thread--But I reallly believe in sizing your system (especially the battery bank first) to your needs. Then "hang" the rest of the support equipment around the battery bank.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Eric L
    Eric L Solar Expert Posts: 262 ✭✭
    Re: possible starter system

    Make sure to check with local battery distributors to get prices. As BB says, you could go with 4 of a larger battery, like an L-16.

    At my local battery distributor:
    225 AH T-105 = $125.
    360 AH L-16 = $169.

    Besides the extra capacity, the L-16 is likely to last longer. A 'no brainer' for the L-16, IF your panels can supply the needed amperage, which your proposed system could.
  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system

    Oops. I meant to change that to L-16's when I changed my mind from 12V to 24V. That would get me up to around 1,000 watts, which is my goal.
    For backup I have 3 generators; 1K, 5K, and 17.5K

    Thanks for the input.
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system

    When I am installing these 6 panels, do I do it in pairs, or two sets of 3. Guide me to a thread on the basics regarding this please.

    thanks, Bo
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: possible starter system

    Either should work. Depending on where they will be installed--you are looking for the minimum solar panel temperature and maximum Voc-array-cold voltage.

    From MorningStar's website, you can find their string calculator:

    http://www.morningstarcorp.com/en/tristar%20mppt
    http://www.morningstarcorp.com/en/strings/calc.php

    Using the Kyocera panels you listed above, either a 2x3 or a 3x2 array will work fine (double check, there are several 235 watt Kyocera panels--I don't know what the electrical differences may be).

    2 string of 3 panels each--You do not use a series protection fuse (needed for 3 or more parallel strings). And you will have a higher voltage Vmp-array and lower Imp-array--Allows you to use smaller gauge wiring from array to charge controller/battery location (and/or have lower wiring losses).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • bmet
    bmet Solar Expert Posts: 630 ✭✭
    Re: possible starter system
    Eric L wrote: »
    Make sure to check with local battery distributors to get prices. As BB says, you could go with 4 of a larger battery, like an L-16.

    At my local battery distributor:
    225 AH T-105 = $125.
    360 AH L-16 = $169.

    Besides the extra capacity, the L-16 is likely to last longer. A 'no brainer' for the L-16, IF your panels can supply the needed amperage, which your proposed system could.

    wow, where is this place? The best price i could find on the internet was over $100 higher.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: possible starter system

    I assume Eric is somewhere around Mobile, AL.

    Yea--Those numbers do sound low...

    -Bill :confused:
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system

    Originally I was going to go with 12v and I remember looking at a site that showed various ways to hook up batteries that kept them more uniform. Now that I am going to go 24V, my only option with 4 L-16's is series, correct? Will this cause more use on the first or last battery? Should they be rotated occasionally?
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: possible starter system

    In theory, there should be no reason to rotate batteries. The are all receiving exactly the same charging/discharging current.

    However, some people do believe it helps. Possibly because the batteries are not all at the same temperature (middle batteries get hotter than end batteries, etc.?).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: possible starter system
    BB. wrote: »
    In theory, there should be no reason to rotate batteries. The are all receiving exactly the same charging/discharging current.

    However, some people do believe it helps. Possibly because the batteries are not all at the same temperature (middle batteries get hotter than end batteries, etc.?).

    They are all receiving the same Direct Current charging current. If there is any high frequency ripple in the DC, it could (in theory) affect batteries differently, depending where they are in the string.

    I have no opinion on the desirability of rotating batteries.
    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • Eric L
    Eric L Solar Expert Posts: 262 ✭✭
    Re: possible starter system
    wow, where is this place?

    Battery Sales and Service in Mobile, AL. These were for US Battery L-16s (they're the regional distributor). $169 +$20 core charge if you don't have one to trade in.

    http://www.batterysalesandservice.com/


    Tell them Eric L. sent you ;)
  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system

    I scaled back.

    3 Kyocera 235 for the roof,
    Magnum MS 2012 inverter,
    Morningstar Tristar 60 amp charge controller, and
    2 Trojan L16-RE

    I'll stay on the smaller side for the RV and go bigger on the log home.
    I went ahead and ordered 9 more of the Kyocera 235 for later.

    I'll pick it all up in Flagstaff on Thurs or Fri and see how much I get done this weekend.
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system

    Do I want to put the 3 panels on the roof in series or parallel?
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system
    BB. wrote: »
    Battery bank size??? Seems a bit small for the panels and inverter you have (if you intend to use "full power")...

    A Nominal system based on your solar array would look something like:
    • 6x 235 watt panels * 0.77 * 1/29 volts charging * 1/0.05 rate of charge = 748 AH @ 24 volts Maximum sized battery bank
    • 6x 235 watt panels * 0.77 * 1/29 volts charging * 1/0.10 rate of charge = 374 AH @ 24 volts "Nominal" sized battery bank
    • 6x 235 watt panels * 0.77 * 1/29 volts charging * 1/0.13 rate of charge = 288 AH @ 24 volts "Small" sized battery bank

    Your current battery bank is only ~225 AH @ 24 volts... You could go larger if you wished.

    And, assuming you run the battery bank at a maximum rate of discharge of C/8 (for flooded cell), the above banks would supply (through your AC inverter):
    • 288 AH * 24 volts * 0.85 eff * 1/8 rate of discharge = 734 watts for "small bank"
    • 374 AH * 24 volts * 0.85 eff * 1/8 rate of discharge = 955 watts for "nominal bank"
    • 748 AH * 24 volts * 0.85 eff * 1/8 rate of discharge = 1,909 watts for "large bank"
    • 225 AH * 24 volts * 0.85 eff * 1/8 rate of discharge = 574 watts for "your bank"

    Note the above supported AC Wattage would be about 2x for starting surges.

    Personally, I do like largish solar arrays--Very nice to get your system quickly recharged the next day... Also, if you have a lot of "daylight loads" (say well pumping, shop, fans, etc.), You can get away with a smaller battery bank if much of your power is used during the middle of the day.

    Also, what are your primary/backup power plans (AC Utility/Generator)?

    Your thoughts?

    -Bill

    I am sure you said your usage two or three pages earlier in the thread--But I reallly believe in sizing your system (especially the battery bank first) to your needs. Then "hang" the rest of the support equipment around the battery bank.

    I get lost with these formulae. Can you run these numbers for the 2 L16RE-Bs and 3 of the 235 Kyocera?
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: possible starter system

    Sure--I think it would look something like this:

    A Nominal system based on your solar array would look something like:
    • 3x 235 watt panels * 0.77 * 1/14.5 volts charging * 1/0.05 rate of charge = 734 AH @ 12 volts Maximum sized battery bank
    • 3x 235 watt panels * 0.77 * 1/14.5 volts charging * 1/0.10 rate of charge = 374 AH @ 12 volts "Nominal" sized battery bank
    • 3x 235 watt panels * 0.77 * 1/14.5 volts charging * 1/0.13 rate of charge = 288 AH @ 12 volts "Small" sized battery bank

    Your Battery Bank option:

    2x L16RE-B 6volt 375@20 Hour Rate connected in series => 375 Amp*Hour at 12 volts

    Assuming you run the battery bank at a maximum rate of discharge of C/8 (for flooded cell), the above banks would supply (through your AC inverter):
    • 375 AH * 12 volts * 0.85 eff inverter * 1/8 rate of discharge = 478 watts "max average 120 VAC power"

    The maximum recommended surge rate for flooded cell deep cycle batteries would be about C/2.5 rate of discharge--So your maximum recommended Surge Wattage to support your AC starting loads would be:
    • 375 AH * 12 volts * 0.85 eff inverter * 1/2.5 rate of discharge = 1,530 watts "max surge 120 VAC power"

    Typically a "good" inverter will be rated for maximum average power and support up to 2x for surge power... In your case the maximum rated inverter (optimum pick) would be around 500 to 800 watts rated power (~1,000 to 1,600 watts maximum surge).

    Larger than an 800 watt rated inverter will (probably) not support rated surge current (~1,530 watts) as batteries discharge and/or age...

    Of course, if your loads are less (charging cell phones, laptop computers, running a few CFL/LED lamps), then you may wish to use a smaller inverter (the MorningStar 300 watt TSW 12 volt inverter is really nice).

    The inverter you picked is (apparently) a 2kW @ 12 volt inverter--It is tough to draw 2kWatts from a small(ish) 12 volt battery bank. The MS 2012 draws about 25 watts base load (no AC loads). I do like the integrated PFC battery charger in the Magnum inverter family--A smaller inverter may be a better choice. The MorningStar only draws 6 watts when turned on with no loads. But--then you have to find a good AC battery charger too.

    The above are all fairly conservative rules of thumbs. You can change things around to improve/change critical performance characteristics (for example, some AGM batteries can support C*4 rate of discharge--i.e., support a load which will drain them in ~15 minutes--Great for UPS applications, probably not needed for a cabin/RV/emergency power usage).

    Does that help?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BoFuller
    BoFuller Solar Expert Posts: 187 ✭✭✭
    Re: possible starter system

    BB,
    Yes that helps a lot! Thank you.

    One more question - should the panels be in parallel or series?
    12 Kyocera 235 panels, 3 Gyll LiFePO4 batteries (previously 16 Trojan L16 RE-B batteries), Outback 3600W 48V system, Generac 11K propane backup generator, NW AZ, off grid, 6,000 ft (system installed in April 2015)