Battery issues

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Comments

  • vtmapsvtmaps Solar Expert Posts: 3,738 ✭✭✭✭
    The509 said:
     What should i do with the 3rd panel while i wait for the other 3? 
    I think the max input voltage for your controller is 150 volts.  If so, you can put the three panels in series (unless you are in a very very cold region). 

    Have you ordered a combiner and DC breakers?  They are required for safety whenever you have 3 or more strings of panels in parallel.  Midnite solar makes a very nice and affordable three position combiner (I have one).

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • The509The509 Registered Users Posts: 22 ✭✭
    Thats actually the one i ordered..
    EQ done, tested those batteries that were in the 1100 range

    #5 went from 1150 1125 1100 to 1200 1160 1150
    #7 went         1200 1150 1150 to 1170 1190 1190

    Changed absorb to 29.4 and Capacity to 200AH
    Will go add 3rd panel back into series now

     
  • Dave AngeliniDave Angelini Solar Expert Posts: 3,329 ✭✭✭✭
    Nice !  You did see the voltage go up to 32V and stay for an hour?
    Ok so now you need to concentrate on getting the average SG up to normal and the new absorb V and time should help. Check it tomorrow.   next  another EQ will help but let it charge normally for a few days.
     Make sure the voltage stays up for the EQ hour.
    If you get some nice sunny days  early next week you should run the electric heater as a load. I would run try and run it for 1 hour to start. 1500 watts should do for now.  Check the SG and see if all the cells are similar.  Good Luck!
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail offgridsolar@sti.net

  • The509The509 Registered Users Posts: 22 ✭✭
    im averaging 9 hours of sun a day. i could put a heater on it much sooner.
  • Dave AngeliniDave Angelini Solar Expert Posts: 3,329 ✭✭✭✭
    You want to start cycling the batteries but you need to get the SG up to 1.265 or so.
    Those 1.150 numbers are not good yet.
    If  they do not improve then it won't hurt to start cycling them. I hope that is not the case.
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail offgridsolar@sti.net

  • The509The509 Registered Users Posts: 22 ✭✭
    i have a question..My batteries seem to be doing better, however i have those 2 that wont come up..My panels wont be here till Tuesday..I was thinking id unhook them tonight, tie them together for 12 volts and put my big charger on them at 60 apms for a few hours..Is that a waste of time?
  • westbranchwestbranch Solar Expert Posts: 4,873 ✭✭✭✭
    Nada to do till you get the additional panels  You need another panel to pair with!  the CC can not do anything with that ype of setup, and may even lower your harvest..
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge, Hughes1100 Sat Modem
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • Dave AngeliniDave Angelini Solar Expert Posts: 3,329 ✭✭✭✭
    if you charge the 2 low batteries with a "big" charger,  it has to hit 15 volts for 2 plus hours. Be careful of heat.
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail offgridsolar@sti.net

  • The509The509 Registered Users Posts: 22 ✭✭
    What would be the most efficient way to string 4 265 watt Kyoceras X 24 volts. Per earlier in the thread I have 8 Trojan L16 I have a total of 6 panels but am finishing up a new addition before connecting them

    I'm using a Xantrex MPPT 160-150
  • PhotowhitPhotowhit Solar Expert Posts: 4,280 ✭✭✭✭

    Unless you have a long distance between the charge controller and the array, Run your strings so they are closest to 2x the battery bank voltage. If you are running a 48 volt battery bank, check to see if you will exceed the limits of your charge controller.

    Next time please include;

    1. Battery bank /system voltage
    2. Distance from array to charge controller
    3. VMP of the panels
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, ForkLift battery. Off grid for @13 of last 14 years. 1000 watts being added to current CC, @2700 watts to be added with an additional CC.
  • The509The509 Registered Users Posts: 22 ✭✭
    Wire length is 8 feet for 4 panels and the other two will be 12 feet from battery bank VMP is 31 volts on all 6 panels. Thinking of adding 2 more in Aug for 8 total

    Bank is 8 Trojans L16 strung at 24
  • vtmapsvtmaps Solar Expert Posts: 3,738 ✭✭✭✭
    The509 said:
    Wire length is 8 feet for 4 panels and the other two will be 12 feet from battery bank VMP is 31 volts on all 6 panels. Thinking of adding 2 more in Aug for 8 total

    Bank is 8 Trojans L16 strung at 24
    Your optimal configuration will be a string length of two (Vmp of string = 62 volts).  After you add the last two panels (8 total), you will need a 4 position combiner box.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • The509The509 Registered Users Posts: 22 ✭✭
    At 24 Volts how many panels do you think my Xantrex could handle ?
  • PhotowhitPhotowhit Solar Expert Posts: 4,280 ✭✭✭✭
    edited May 2016 #45
    The509 said:
    At 24 Volts how many panels do you think my Xantrex could handle ?


    It's an interesting question. I suspect you can put as many on as you want and the controller will handle them, reducing output to 60 amps. Most panels that could cost effectively be handled, is limited by the 60 amp maximum output, at @28 volts would be 60amps x 28volts = 1680 watts and since panels NOCT (Normal Operating Cell Temperature) value runs about 75% of the panel rating, you can add a 1/3 of that value or about 2240 watts.

    8 panels for 265 watts x 8 = 2120 watt array, looks like a pretty good number.

    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, ForkLift battery. Off grid for @13 of last 14 years. 1000 watts being added to current CC, @2700 watts to be added with an additional CC.
  • The509The509 Registered Users Posts: 22 ✭✭
    off an on for the last 6 days, my bank would show 26 to 27 at sundown. However if I turn one 24 volt 60 watt bulb on it drops to 22-23 volts and dims. This isn't every night. More like every other night. Could this be an indication that my bank has issues or possible my Xantrex isn't working correctly?
  • BB.BB. Super Moderators Posts: 26,872 admin
    Those batteries are not happy... You can see what a nominal battery State of Charge should be (Trojan):

    http://www.trojanbattery.com/tech-support/battery-maintenance/

    State of Charge as Related to Specific Gravity and Open Circuit Voltage
    Percentage of ChargeSpecific Gravity Corrected ToOpen-Circuit Voltage

     6v8v12v24v36v48v
    1001.2776.378.4912.7325.4638.2050.93
    901.2586.318.4112.6225.2437.8550.47
    801.2386.258.3312.5025.0037.4949.99
    701.2176.198.2512.3724.7437.1249.49
    601.1956.128.1612.2724.4836.7248.96
    501.1726.028.0712.1024.2036.3148.41
    401.1485.987.9711.8923.9235.8747.83
    301.1245.917.8811.8123.6335.4447.26
    201.0985.837.7711.6623.3234.9746.63
    101.0735.757.6711.5123.0234.5246.03

    In theory, your SG should be upwards of 1.258 to 1.277... You have (very roughly) less than 30% capacity on some of them now.

    Try cycling the battery (discharge by 25% or more) then recharge again (maybe 10 cycles minimum????). If the SG does not begin to rise, you are probably not going to get them to recover.

    Next step is probably to determine your loads and remind me of your present solar array configuration/Wattage. If you go with 8x 265 Watt panels (2,120 Watts total) on a 24 volt battery bank, the nominal bank AH rating suggestion would be:
    • 2,120 Watts * 1/29 volts charging * 0.77 panel+controller deratings * 1/0.05 rate of charge = 1,126 AH @ 24 volts max bank
    • 2,120 Watts * 1/29 volts charging * 0.77 panel+controller deratings * 1/0.10 rate of charge = 564 AH @ 24 volts nominal
    • 2,120 Watts * 1/29 volts charging * 0.77 panel+controller deratings * 1/0.13 rate of charge = 433 AH @ 24 volts minimum
    If you rarely use electric power (backup power) or are seasonal (weekends/summer), then 5% rate of charge can work.

    If you use the system heavily/daily (over 9 months a year), then 10% rate of charge is better... You can go upwards of 13% rate of charge on solar (10-13%+ rate of charge helpful if you have significant day time loads).

    In general, it is usually easier to manage a battery bank that has significant "over paneling" (and you will probably, on average, have longer battery life too).

    Hours of sun per day appears to be highly seasonally dependent:
    http://pvwatts.nrel.gov/pvwatts.php
    MonthSolar Radiation
    ( kWh / m2 / day )
    January2.32
    February2.96
    March4.26
    April5.12
    May5.57
    June5.66
    July6.98
    August6.65
    September5.62
    October4.48
    November2.23
    December1.92
    Annual4.48
    Toss the bottom three months (assume genset support through bad weather/low sun angles and your average February harvest (break even month) would be:
    • 2,120 Watt array * 0.52 average AC off grid system eff * 2.96 hours of Feb sun = 3,263 Watt*Hours (120 VAC) per average February day
    Anyway--Some starting math to look at what could be your new battery bank with the estimated solar array and sun for your approximate location.

    -Bill


    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • The509The509 Registered Users Posts: 22 ✭✭
    Thanks for that info. My sun is actually a little more as I'm around 3500 feet and see more then those below me


    I'm gonna test the bank today and see where I'm at. I currently have 6x265 watt panels and 8 Trojan X 320 AmP hours per.
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