Newbie looking for help!

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Comments

  • Rockcrawler
    Rockcrawler Registered Users Posts: 18
    Re: Newbie looking for help!
    BB. wrote: »
    For the most part, you can parallel different controllers to one battery bank (assuming proper electrical connections).

    The battery charging voltage will end up being set by the controller with the highest output voltage...

    If your solar charger is a 3 stage type--and is currently set to "float" at 13.6 volts... And your AC charger is a 2 stage type that is set for bulk/absorb charging at 14.4 volts--the AC charger will simply take the battery to 14.4 volt.

    If both are 3 stage chargers--You still will have the condition where charger A has decided on 13.6 volts and charger B is still in absorb at 14.4 volts for another hour.

    When the batteries are not fully charged, both controllers will supply their maximum rated current into the battery bank until battery reaches the target voltage.

    You may be able to set the chargers for different Absorb voltage... Set the Solar to 14.5 volts and set the AC charger to 14.2 volts. Then the AC charger will only charge if the battery voltage is low and there is insufficient solar for charging.

    Or you can set the genset to 14.5 volts for maximum charging current (start the genset first thing in the morning before ~9am) to get the most energy from the genset into the battery bank quickly (gensets are more efficient if loaded to ~>50% of rated load). Then shutdown the AC charger/genset and let the solar panels finish up charging the rest of the day.

    The above are just a couple of examples you can use... Some of this depends on how often you use your genset and how much loading you have. Normally--I like to reduce genest runtime and increase fuel efficiency--Generally this means maximizing battery charging current (charging discharged bank up to ~80-90% state of charge with near 100% of available charger current / generator maximum loading) and letting the solar array finish of the charging (say after 2-3 days of no sun).

    Make sense?

    -Bill

    Yes, but I think I need to get one good charge controller before I get two. It is good to know for the future if end up needing to do something like you described.
  • Rockcrawler
    Rockcrawler Registered Users Posts: 18
    Re: Newbie looking for help!
    hillbilly wrote: »
    Not sure what you mean about Equalizing them wrong. Sounds like they maybe just didn't actually need equalizing. Some bubbling is normal when absorbing or EQing, no bubbling at all while charging would indicate insufficient charging, constant vigorous bubbling for hours and hours on a regular basis will shorten the batteries lifespan. If the difference between all cells was within .010, that's really good particularly with 3 parallel strings; mine never get that close even after EQ'ing :-(

    Think of EQ'ing as a way to insure that all cells get returned to 100% on a semi regular basis; meaning don't obsess on having to get all cells completely full every single day, but don't go months at a time with some cells only getting up to 80-90% full either. Usually in regular cycling you'll find that there are imbalances in the charging and discharging, thus some cells end up getting full early and some may not quite get completely full. If this type of cycling were to continue for extended periods of time the imbalances can grow, and eventually this will lead to some cells working much harder and having their life span shortened while other cells will begin to sulphate. Hence there is some range of opinions on exactly how and when to EQ, but the idea is the same: use it as a tool when needed to balance and recharge all cells, but only if/when needed.

    Thanks, I just meant that I EQ'd them too long. I was using saws, vacum, TV, etc throughout the day and that's what got me thinking that if I am using the generator for a while, 5+ hours, will I hurt my batteries.
  • Rockcrawler
    Rockcrawler Registered Users Posts: 18
    Re: Newbie looking for help!
    hillbilly wrote: »
    Sometimes it can be a bit tricky/buggy when utilizing more than one charging source at a time. I forget which chargers do you have? One issue that I've had from using the method that Bill suggests (which is in theory the ideal way to utilize a generator), is that if I let the generator fill the batteries a bit too long is that the PV charge controller will think that the batteries are completely full and stop charging, and then go into float after the generator is turned off. This means that I have to manually reset the charge controller, or sometimes tell it to "EQ" while I turn the EQ voltage setting to my actual absorb voltage. One thing that helps a bit with this is to set the absorb voltage setpoint slightly lower on the AC/DC charger than on your PV charge controller... if possible.

    I only have one charger. It is a Power Center APT 3. Generator is wired to the inverter, inverter to the charge controller, pvs to the charge controller. Like I said before I have the little knobs on my inverter, Trace Engineering, that you have to dial in. The only thing I changed from the previous owner's settings were the tempereature for outside air.
  • Rockcrawler
    Rockcrawler Registered Users Posts: 18
    Re: Newbie looking for help!
    niel wrote: »
    just to clarify, it is good to have the bubbling to mix the electrolyte, but that's while charging a battery that is not 100% soc. to do this with a battery that is charged already is over charging it and it will need water much more often.

    Makes sense, Thanks.
  • Derik
    Derik Solar Expert Posts: 82 ✭✭✭✭
    Re: Newbie looking for help!

    Sounds like your batteries are fully charged and the Hydrometer readings are off the charts according to the trojan booklet that came with my L-16RE B batteries. The battery salesman told me not to expect higher readings that 1.255.