At least 2 issues with my system

2»

Comments

  • gicamucigicamuci Registered Users Posts: 32 ✭✭
    BB. said:
    The single "cool string" is being hammered pretty well with your present usage and a second string is really needed (for loads/65% discharge overnight/high charging current).

    -Bill
    Thanks Bill.
    The 65% is the SOC in the morning. So overnight I am pulling 35% from them. I did set my inverter so overnight, if the SOC gets to 65%, will switch to the grid.
    I thought about charging the 2 bats together as a 12V one, but I decided to g with one at the time.
    Even with just one bat charging is taking a lot of time and the charger timed out this morning. I had to reset it. Still charging number 1 for now.
    5.1kW, 12 × 250W + 4 x 275W + 3 x 330W (driving the pool pump MPPT controller or charging batteries on cloudy days) solar panels , FM80 MPPT CC, WavePower 6kW pure sine inverter, (16 x Trojan 105Plus - replaced) 16 x Dyno D90 in 8s2p strings 420Ah @ 48V battery bank.
    Champion Dual Fuel 7.2KW gasoline/6.5KW propane gen for emergencies only.

  • Dave AngeliniDave Angelini Solar Expert Posts: 6,226 ✭✭✭✭✭
    gicamuci said:
    The so called "hot" battery bank is now offline while I try and bring up the two batteries that were low on SG.
    Those around 50A are going to the online good string of batteries that have 225Ah @48V.

    gicamuci means "Gică" (a name, much like George in English) plus "muci" which means snotty (in English, mot-a-mot), but I am using is more as "novice". So something like "novice George". I was born, raised and lived in Romania until I turned 30. So that's a Romanian "thing" as my name is not George, but Alex.

    Thanks Alex!  Yea the comment on the 50A is really telling you 10% of the 225AH. You should be limiting charge current to 25 or 30 amps.
    A bit nicer in winter in the DR. Do you miss the seasons of R ?
    "we go where power lines don't" Sierra Nevada mountain area
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • gicamucigicamuci Registered Users Posts: 32 ✭✭
    I made the change on the CC to limit to 30A, for tomorrow though. Today they are already on Floating.

    A bit nicer in winter in the DR. Do you miss the seasons of R ?
    Only the 4 seasons, yes. Then I moved to Canada where there were truly 2 seasons (summer and winter).
    Yes the winter is way nicer here in DR :)
    5.1kW, 12 × 250W + 4 x 275W + 3 x 330W (driving the pool pump MPPT controller or charging batteries on cloudy days) solar panels , FM80 MPPT CC, WavePower 6kW pure sine inverter, (16 x Trojan 105Plus - replaced) 16 x Dyno D90 in 8s2p strings 420Ah @ 48V battery bank.
    Champion Dual Fuel 7.2KW gasoline/6.5KW propane gen for emergencies only.

  • gicamucigicamuci Registered Users Posts: 32 ✭✭
    So for tropical climate, what battery chemistry would be recommended ?
    Here in DR in "summer" months :) even at night the ambient temp won't go under 26C.
    5.1kW, 12 × 250W + 4 x 275W + 3 x 330W (driving the pool pump MPPT controller or charging batteries on cloudy days) solar panels , FM80 MPPT CC, WavePower 6kW pure sine inverter, (16 x Trojan 105Plus - replaced) 16 x Dyno D90 in 8s2p strings 420Ah @ 48V battery bank.
    Champion Dual Fuel 7.2KW gasoline/6.5KW propane gen for emergencies only.

  • gicamucigicamuci Registered Users Posts: 32 ✭✭
    Overnight I switched on grid so today I started with a full or close to full string. They brieflly went to Bulk and then a bit of Absorbing followed by Floating for 5 minutes or so.
    All this so I am EQing the good string. Currently there are 29A @ 62V going into them. I know Trojan says 64.8V, but had to go lower because of the ambient temp.
    Is this rate of 29A @ 62V a good rate for this string of 6V bats in series with 225Ah capacity ?
    They are nicely bubbling.

    5.1kW, 12 × 250W + 4 x 275W + 3 x 330W (driving the pool pump MPPT controller or charging batteries on cloudy days) solar panels , FM80 MPPT CC, WavePower 6kW pure sine inverter, (16 x Trojan 105Plus - replaced) 16 x Dyno D90 in 8s2p strings 420Ah @ 48V battery bank.
    Champion Dual Fuel 7.2KW gasoline/6.5KW propane gen for emergencies only.

  • Dave AngeliniDave Angelini Solar Expert Posts: 6,226 ✭✭✭✭✭
    It sounds a bit hi but as long as you keep an eye on them, give it a try. Take all precautions and make sure the area is clear of easy burning materials. Feel the terminals and wear eye protection. You might save them and you might blow them. There are a few failure modes.

    People often knock FLA batteries but in most cases the people are the weak link. I have a client in Arizona that changes his Lead acid bank every 5 years and they are still good, just lost capacity. He takes good care of them and he has to in a 100F+ ambient battery room.

    Your problems stem from using battery strings and not doing the full maintenance. Not bad for a first set so do not take it wrong. I miss the island rum. Who is best now?
    "we go where power lines don't" Sierra Nevada mountain area
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • gicamucigicamuci Registered Users Posts: 32 ✭✭
    edited October 2020 #38
    When I started the EQ the current was under 28A and now after an hour is at 32A. Is it normal ?
    Forgot to add: they are cool to the touch. Well... nothing is cool on this island unless it came out from a fridge. But at the ambient temp which is now 31°C.
    Either Barcelo or Brugal. They are both good. I personally like the white Brugal :) but not the 51° just the normal one on ice.


    5.1kW, 12 × 250W + 4 x 275W + 3 x 330W (driving the pool pump MPPT controller or charging batteries on cloudy days) solar panels , FM80 MPPT CC, WavePower 6kW pure sine inverter, (16 x Trojan 105Plus - replaced) 16 x Dyno D90 in 8s2p strings 420Ah @ 48V battery bank.
    Champion Dual Fuel 7.2KW gasoline/6.5KW propane gen for emergencies only.

  • gicamucigicamuci Registered Users Posts: 32 ✭✭
    I chickened out after an hour an a half of EQ. The ambient temp was as 33°C and batteries were at 40°C.
    Can an equalizing session be split over a two or three days shorter sessions ?


    5.1kW, 12 × 250W + 4 x 275W + 3 x 330W (driving the pool pump MPPT controller or charging batteries on cloudy days) solar panels , FM80 MPPT CC, WavePower 6kW pure sine inverter, (16 x Trojan 105Plus - replaced) 16 x Dyno D90 in 8s2p strings 420Ah @ 48V battery bank.
    Champion Dual Fuel 7.2KW gasoline/6.5KW propane gen for emergencies only.

  • BB.BB. Super Moderators, Administrators Posts: 32,804 admin
    edited November 2020 #40
    Yes stop EQ on hot batteries and resume after they have cooled.
    EQ... A good rate of charge is 5% to 2.5%.
    225 ah x 0.05 = 11.25 amps target
    Lower your EQ voltage and take time (in my humble opinion).
    30 amps into 225 AH is too high. Especially in a tropical climate.
    In EQ almost all charging energy is turned into gassing and heat. Except for the "low SG" cells that are charging to full.
    Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • gicamucigicamuci Registered Users Posts: 32 ✭✭
    Your problems stem from using battery strings and not doing the full maintenance. Not bad for a first set so do not take it wrong.
    No worries. Next set of batteries will sure be some 8 x L16s as suggested earlier, if I will find them to buy on the island.

    Number 1 did not improve at all after 2 days of charging it. Those 2 cells are still at 1.220 SG. I guess number 2 will be the same with its cell at 1.220
    I am not really prepared to change all 16 of them at this time and I might try buying just 2 to replace the bad ones and see how far I can go with them (I know is not recommended to mix new and old bats).
    I did limit the charge current on the FM80 so the remaining 8 will not suffer.
    Thank you guys for your time and valuable advice. Some good learning on this discussion.
    5.1kW, 12 × 250W + 4 x 275W + 3 x 330W (driving the pool pump MPPT controller or charging batteries on cloudy days) solar panels , FM80 MPPT CC, WavePower 6kW pure sine inverter, (16 x Trojan 105Plus - replaced) 16 x Dyno D90 in 8s2p strings 420Ah @ 48V battery bank.
    Champion Dual Fuel 7.2KW gasoline/6.5KW propane gen for emergencies only.

  • Dave AngeliniDave Angelini Solar Expert Posts: 6,226 ✭✭✭✭✭
    If you can get 2 at a reasonable price on the island and you understand that it will be temporary. Does DR have Costco?
    You can get a golf battery in most costco locations. A bit cheaper than a Trojan golf battery. For this kind of "not optimum" operation it really is not going to matter. You are going to have to really watch them !  A decent name brand near 400AH battery should be around $350 each. Drop me an email and I can hook you up with someone I know who does this alot.

    What is the good rum make in DR.  I can't remember but when we were anchored there we bought a case. Just add ice!
    "we go where power lines don't" Sierra Nevada mountain area
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • gicamucigicamuci Registered Users Posts: 32 ✭✭
    There's no Costco on the island. There's a similar store Pricemart which requires membership which I don't have yet.
    Only 2 models of batteries are everywhere here. The Trojan's T105Plus and Trace T225. For the price difference of US $20  I'll buy a Trojan one. A friend told me that L16 batteries are starting to appear in some stores.
    5.1kW, 12 × 250W + 4 x 275W + 3 x 330W (driving the pool pump MPPT controller or charging batteries on cloudy days) solar panels , FM80 MPPT CC, WavePower 6kW pure sine inverter, (16 x Trojan 105Plus - replaced) 16 x Dyno D90 in 8s2p strings 420Ah @ 48V battery bank.
    Champion Dual Fuel 7.2KW gasoline/6.5KW propane gen for emergencies only.

  • gicamucigicamuci Registered Users Posts: 32 ✭✭
    My conclusion is that I have an energy production which is too big for the battery bank I have (or I need a bigger battery bank). During daytime our house pulls somewhere between 15A to 20A. Plus the charge rate recommend for my 450Ah battery bank (45A) it gives me some 60A or 65A for the limit I should use on the FM80 with the whole battery bank in service. Did I get it right ?

    5.1kW, 12 × 250W + 4 x 275W + 3 x 330W (driving the pool pump MPPT controller or charging batteries on cloudy days) solar panels , FM80 MPPT CC, WavePower 6kW pure sine inverter, (16 x Trojan 105Plus - replaced) 16 x Dyno D90 in 8s2p strings 420Ah @ 48V battery bank.
    Champion Dual Fuel 7.2KW gasoline/6.5KW propane gen for emergencies only.

  • PhotowhitPhotowhit Solar Expert Posts: 5,909 ✭✭✭✭✭
    gicamuci said:
    My conclusion is that I have an energy production which is too big for the battery bank I have (or I need a bigger battery bank). During daytime our house pulls somewhere between 15A to 20A. Plus the charge rate recommend for my 450Ah battery bank (45A) it gives me some 60A or 65A for the limit I should use on the FM80 with the whole battery bank in service. Did I get it right ?

    Yes, if you have a regular load that high, you should try to account for it.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • gicamucigicamuci Registered Users Posts: 32 ✭✭
    edited November 2020 #46
    I was lucky to find two used good Trojan 105 batteries and replaced number 1 and 2 (SG didn't recover on those cells).
    The 2 "new" ones are just 6 months older than the rest I have.
    I gave them a charge individually and then I EQ the string.
    All is good now 😊
    I also moved the cables from the negative post on the upper string to the lower string.
    While under load (20A) 9A is coming from the upper string and 11A from the lower string (the hot one with issues).
    It is way better than before when the lower string was stressed under load.
    5.1kW, 12 × 250W + 4 x 275W + 3 x 330W (driving the pool pump MPPT controller or charging batteries on cloudy days) solar panels , FM80 MPPT CC, WavePower 6kW pure sine inverter, (16 x Trojan 105Plus - replaced) 16 x Dyno D90 in 8s2p strings 420Ah @ 48V battery bank.
    Champion Dual Fuel 7.2KW gasoline/6.5KW propane gen for emergencies only.

  • gicamucigicamuci Registered Users Posts: 32 ✭✭
    Now I have another issue... 
    While the 2 strings of 8 batteries in series are now seeing almost the same current while charging and temperature of all batteries is just 2 or 3 degrees Celsius above ambient temperature, when it comes to discharging, everything changes.
    Current is being drawn from only one string while the other one (where the two "new" batteries are) sees almost nothing drawn from it.
    What's happening ?
    5.1kW, 12 × 250W + 4 x 275W + 3 x 330W (driving the pool pump MPPT controller or charging batteries on cloudy days) solar panels , FM80 MPPT CC, WavePower 6kW pure sine inverter, (16 x Trojan 105Plus - replaced) 16 x Dyno D90 in 8s2p strings 420Ah @ 48V battery bank.
    Champion Dual Fuel 7.2KW gasoline/6.5KW propane gen for emergencies only.

  • BB.BB. Super Moderators, Administrators Posts: 32,804 admin
    Under load, check the voltage of each battery... Ideally, all batteries should be about the same voltage (within a few 0.10 volts). I would guess you will see one (or possibly two) batteries in the string not providing current with low voltage. (checking per battery voltage during charging too--Again, you are looking for batteries that are "different").

    And--those batteries--Might need replacing too.

    Check the SG, wiring, etc... I don't think you have a wiring issue (since the charging current is being shared). This website does a good job of explaining wiring of parallel battery strings:

    http://www.smartgauge.co.uk/batt_con.html

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Dave AngeliniDave Angelini Solar Expert Posts: 6,226 ✭✭✭✭✭
    Like the movie ground hog day this old story just keeps going over and over. Battery strings are to be avoided at all cost unless the system is managed.

    My advice for managing,  just get a battery switch and use each bank individually and charge them together. It is the cost of not designing correctly and when you replace the batteries you can make the correction. Good Luck!
    "we go where power lines don't" Sierra Nevada mountain area
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • 706jim706jim Solar Expert Posts: 484 ✭✭✭✭
    The battery switch is a good idea even for two strings. I run both of mine and charge them at the same time but it has been really handy to keep the inverter running while I change connecting cables or clean them. (Does anyone else keep two sets of interconnect cables and swap them every few months?)
    Island cottage solar system with 2500 watts of panels, 1kw facing southeast 1.3kw facing southwest 170watt ancient Arco's facing south. All panels in parallel for a 24 volt system. Trace DR1524 MSW inverter, Outback Flexmax 80 MPPT charge controller 8 Trojan L16's. Insignia 11.5 cubic foot electric fridge. My 29th year.
  • gicamucigicamuci Registered Users Posts: 32 ✭✭
    So I bought this DC Power Supply in order to equalize the offending batteries individually:
    It works great in my opinion.
    5.1kW, 12 × 250W + 4 x 275W + 3 x 330W (driving the pool pump MPPT controller or charging batteries on cloudy days) solar panels , FM80 MPPT CC, WavePower 6kW pure sine inverter, (16 x Trojan 105Plus - replaced) 16 x Dyno D90 in 8s2p strings 420Ah @ 48V battery bank.
    Champion Dual Fuel 7.2KW gasoline/6.5KW propane gen for emergencies only.

  • mike95490mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    gicamuci said:
    So I bought this DC Power Supply in order to equalize the offending batteries individually:
    It works great in my opinion.
    Wow, that's a nice supply. and the price is amazing.
    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 ,

Sign In or Register to comment.