Mixing 2x6v 210ah with 1x12v 130ah

KhellSkKhellSk Registered Users Posts: 63 ✭✭
2x 6v series; are relatively new and 210ah
1x 12v are 6month old and 130ah

Goal; parallel 2x6v with 12v for a 12v bank
_____________________________________________
[2x Flooded  6v 210ah][12v 30a 400wMax CC]
[5x 48w 15.9Vmp + 1x 100w 17Vmp]


Mixing 2x6v 210ah with 1x12v 130ah 5 votes

Yay
20%
jonr 1 vote
Nay
80%
mike95490PhotowhitmcgivorJLFH 4 votes

Comments

  • BB.BB. Super Moderators, Administrators Posts: 28,593 admin
    If you already have the batteries... Why not.

    However, they should be the "same" vendor/type of battery... You don't want mix (for example) a flooded cell deep cycle battery with AGM or GEL (flooded cell deep cycle batteries work best when charged at ~14.8 volts or so, AGM need ~14.4 volts max, and GEL need ~14.2 volts max).

    Also, you really do not want to mix a Deep Cycle battery with a car starting battery (SLI--Starting, Lighting, and Ignition). SLI batteries really do not like to be cycled much below 85% State of Charge. And your deep cycle works fine when cycled to 50% or less SoC (when recharged promptly--Next day).

    If you have nothing to lose (already have the batteries and if they go kaput--You have not lost anything)...

    -Bill "details matter" B.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • KhellSkKhellSk Registered Users Posts: 63 ✭✭
    edited December 2018 #3
    @BB. All Trojans flooded.

    @BB.  Problem is that right now due to problem explained on my "32cells 15.9v garbage" thread, i have a hell of a time recharging them fully when cloudy. I simply cannot charge the last 25% of my battery 12 days out of 14. I get stuck st 12.2 12.3 most of.the time even if sunny.

    I cant decide if I ;

    1. Keep with my pwm, stay all parallel with my 5x 48w 32cells + 1x 100w 36cell and add blocking diodes(my favorite so far but im an idiot so might be the worst )

    2. Ditch the pwm cc, ditch the 100w 36cells and go 5x 32cells parallel  direct onto batteries with blocking diodes. ( your suggestion)

    3. Ditch the 100w 36cells and 1 of the 32cells then go 2parallel 2 series  on a mppt for 150$ ( @Photowhit @mcgivor @jonr suggestion )

    (By ditch i mean remove from main system and store or use somewhere else)

    I just dont know how much more watts i would gain from 2 or 3 due the constant shading the branches ( leaves during summer)

    #2 seems like it would work for fully charging the battery but would require baby sitting.
    _____________________________________________
    [2x Flooded  6v 210ah][12v 30a 400wMax CC]
    [5x 48w 15.9Vmp + 1x 100w 17Vmp]


  • EstragonEstragon Registered Users Posts: 3,334 ✭✭✭✭✭
    With constant shading from branches, I'd want to solve that problem first.
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • jonrjonr Solar Expert Posts: 1,234 ✭✭✭✭
    Yay
    +1 on what Bill said in #2.

    210+130 = 340 ah.   At 13% charge rate, you should have 44A of charging.  You have < 1/2 of that.  In addition to being under paneled, you have shading and cloud problems, which has a big negative effect.   

    Lead acid batteries will quickly be ruined due to lack of proper charging (both AH and time).  Lithium batteries would be more suited to what you are doing.

    I am available for custom hardware/firmware development

  • KhellSkKhellSk Registered Users Posts: 63 ✭✭
    Estragon said:
    With constant shading from branches, I'd want to solve that problem first.
    Not cutting down trees brother. Its maple farm
    _____________________________________________
    [2x Flooded  6v 210ah][12v 30a 400wMax CC]
    [5x 48w 15.9Vmp + 1x 100w 17Vmp]


  • EstragonEstragon Registered Users Posts: 3,334 ✭✭✭✭✭
    Can you trim the offending branches without taking out the trees?  If not, can you relocate the panels?  Shaded panels won't work well.
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • BB.BB. Super Moderators, Administrators Posts: 28,593 admin
    edited December 2018 #8
    More or less, anything there is a bit of shade on one panel (just one cell shaded of a panel), that panel will produce zero useful current for charging.

    There are lots of arguments about whether a bunch of panels in series on a MPPT type charge controller works better or worse vs a bunch of panels in parallel on a PWM controller... The end result, shade/cloudy weather/etc. just kills solar panel output.

    If you cannot get shade free panels from ~9am to 3pm, you will have problems. If they are under dappled sunlight all day long, or at least most of the day, there is not much the panels can do for charging.

    Is there any way you can move the panels a few 10's or, perhaps, 100 feet or so and get them in better sun?

    At this point, just connect your 32 cell panels in parallel without series diodes (you really should have ~7.5 to 10 amp series fuses in front of each panel) and get those batteries charging. If you cannot, then MPPT or PWM controllers are not going to do much for helping to charge your batteries.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mountainmanmountainman Registered Users Posts: 161 ✭✭
    edited December 2018 #9
    Instead of ditching panels you are already low on power (shading under paneled etc). Why not add another 100 watt 36 cell  to the pwm you have. Series the 5 45s on a 150 voc mppt. Run both charge controllers on the same bank. 
    Blue ridge mts. Renogy 400 watts manual tracking . Epever mppt 30. 2 GC 208 [email protected] volts 300 watt psw inverter. 2 kw genny. Iota 45.
  • EstragonEstragon Registered Users Posts: 3,334 ✭✭✭✭✭
    Agree with Bill... at 12.2-12.3 the batteries are under 75% and should be fully charged one way or another soon.
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • jonrjonr Solar Expert Posts: 1,234 ✭✭✭✭
    Yay
    I think that most people who rely on solar to charge lead acid get a generator and use it sometimes.

    I am available for custom hardware/firmware development

  • PhotowhitPhotowhit Solar Expert Posts: 4,799 ✭✭✭✭
    Nay
    KhellSk said:
    I get stuck st 12.2 12.3 most of.the time even if sunny.
    If they are charging, without load and are at 12.2-12.3, they are likely not 50% full! This is measuring the incoming voltage from the array sending current into the battery and artificially raising the resting voltage. If disconnected from the charging source, I suspect after an hour or 2 they will fall below 12 volts without a load. If this is where you find them when you come home with the sun down, then you are correct in your SOC assessment.

    Undercharging batteries kills them quicker than anything. Another reason for not having more batteries connected to the same source.

    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • KhellSkKhellSk Registered Users Posts: 63 ✭✭
    edited December 2018 #13
    Photowhit said:
    KhellSk said:
    I get stuck st 12.2 12.3 most of.the time even if sunny.
    If they are charging, without load and are at 12.2-12.3, they are likely not 50% full!   They charge during the day often stay around 12.6 12.7sometimes it foes go.at 13something) then at night after its dark, even without using any power  
    Its usually around 12.3 ish.

    Makes me sad... 



    ******did it again today. That doesnt make sense why sould it charge the first 2 3rds but not the rest... during summer i had no problem filling it up... im not gonna touch it tonight and let it charge again tomorow
    _____________________________________________
    [2x Flooded  6v 210ah][12v 30a 400wMax CC]
    [5x 48w 15.9Vmp + 1x 100w 17Vmp]


  • KhellSkKhellSk Registered Users Posts: 63 ✭✭
    edited December 2018 #14
    BB. said:
    More or less, anything there is a bit of shade on one panel (just one cell shaded of a panel), that panel will produce zero useful current for charging.

    There are lots of arguments about whether a bunch of panels in series on a MPPT type charge controller works better or worse vs a bunch of panels in parallel on a PWM controller... The end result, shade/cloudy weather/etc. just kills solar panel output.

    If you cannot get shade free panels from ~9am to 3pm, you will have problems. If they are under dappled sunlight all day long, or at least most of the day, there is not much the panels can do for charging.

    Is there any way you can move the panels a few 10's or, perhaps, 100 feet or so and get them in better sun?

    At this point, just connect your 32 cell panels in parallel without series diodes (you really should have ~7.5 to 10 amp series fuses in front of each panel) and get those batteries charging. If you cannot, then MPPT or PWM controllers are not going to do much for helping to charge your batteries.

    -Bill
    Cant move the panels, but last summer i was able go fill up no problems. Yes sun is higher and negates the shading factor for hours straight. I cut down like 20 spruces and still cant get past 12.3

    I dont give up easily but Im about to. Im getting the diodes next week and the inline fuse holders next weeks....

    **one thing i change isnthe angle.of.the panel from 71 to 21. When the sun makes it above its not perpendiculatlr sunlight. It is only in the morning when it fight through trees and branch(its does.make it to 12.7 tho)

    I think ill bring em back up to 45° and focus on the light i get when suns get above trees
    _____________________________________________
    [2x Flooded  6v 210ah][12v 30a 400wMax CC]
    [5x 48w 15.9Vmp + 1x 100w 17Vmp]


  • mcgivormcgivor Solar Expert Posts: 2,646 ✭✭✭✭✭
    edited December 2018 #15
    Nay
    The longer the batteries sit at a low state of charge the greater the chance sulfation will begin to form hard crystals which are extremely difficult to break down, if at all possible  without  permanent damage. As a temporary solution have them fully charged with a grid powered  charger, this may allow what minimal input you have maintain them.

    The use of a generator seems like the only solution during winter, given the array cannot be relocated, nor trees be removed, short of going up where there is less shading, as in elevated array, there are few options, as even partial shading can cut production by as high as 90% or more.   


    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery bank 
    900W  3 × 300W No name brand Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah FLA 24V nominal as a backup system. 
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergencies and welding.
  • littleharbor2littleharbor2 Solar Expert Posts: 1,178 ✭✭✭✭
    edited December 2018 #16
    Why don't you get some modern panels with proper voltage, overpanel due to shading and get rid of those ancient panels? You might even be able to equalize your batteries back into a healthy state before they become almost worthless scrap.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • KhellSkKhellSk Registered Users Posts: 63 ✭✭
    edited December 2018 #17
    Why don't you get some modern panels with proper voltage, overpanel due to shading and get rid of those ancient panels? You might even be able to equalize your batteries back into a healthy state before they become almost worthless scrap.
    Thats what im thinking about doing but im all out of money cause. I might try to sell the 130ah trojan with the 5x 48w and the pwm for cheap.

    I looked up panels and CC

    And i foubd something thats seems to fit my bank.

    2x 300w 32Vmp ( with maxim optimizer) 
    EPever mppt xtra 12/24v,  100v max


    I was trying to figure out the difference between 

    EPever
    Tracer 3210AN And XTRA  3210

    Would you have a look maybe it would be more obvious to you ?



    _____________________________________________
    [2x Flooded  6v 210ah][12v 30a 400wMax CC]
    [5x 48w 15.9Vmp + 1x 100w 17Vmp]


  • jonrjonr Solar Expert Posts: 1,234 ✭✭✭✭

    I am available for custom hardware/firmware development

  • mountainmanmountainman Registered Users Posts: 161 ✭✭
    Fwiw the tracer series with an A is positive ground. An is negative. Xtra is negitive ground marine high moisture.I have a 3210 An  In low light it does not work very well. Cloudy days I see 16 volts and .5 amps 8 watts!!!
    With 4 100 watt panels 2s2p. But In full sun it works great.330 watt peaks 25 amps.  my pwm 30 amp controller on my other 4 100 watt array all in parrelell 22 amps and 308 watts. on cloudy days 4 amps 56 watts
    Blue ridge mts. Renogy 400 watts manual tracking . Epever mppt 30. 2 GC 208 [email protected] volts 300 watt psw inverter. 2 kw genny. Iota 45.
  • KhellSkKhellSk Registered Users Posts: 63 ✭✭
    Fwiw the tracer series with an A is positive ground. An is negative. Xtra is negitive ground marine high moisture.I have a 3210 An  In low light it does not work very well. Cloudy days I see 16 volts and .5 amps 8 watts!!!
    With 4 100 watt panels 2s2p. But In full sun it works great.330 watt peaks 25 amps.  my pwm 30 amp controller on my other 4 100 watt array all in parrelell 22 amps and 308 watts. on cloudy days 4 amps 56 watts
    okay so MPPT works a lot better with good sun exposure and shit on cloudy days but PWM are average with full sun, and not so shit on cloudy days
    _____________________________________________
    [2x Flooded  6v 210ah][12v 30a 400wMax CC]
    [5x 48w 15.9Vmp + 1x 100w 17Vmp]


  • BB.BB. Super Moderators, Administrators Posts: 28,593 admin
    MPPT and PWM controllers are not magic... Shaded solar panels (or dense cloud cover) just do not provide much energy.

    If one part of the array is in sun and another part in some sort of shade, wiring changes and possibly a different controller could help. But not that much.

    Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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