softdown ✭✭✭✭


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  • Re: Did I destroy my battery bank??

    Photowhit said:
    Please just burn that book!

    Wiring can promote equal resistance across a battery bank, part of the equal resistance would include where the energy is coming into and out of the battery bank. This is not noted in the wiring diagram hence this shows a lack of understanding. So burn the book. Do not pass it along to another person! You would be just passing along bad or improperly presented information. I say that because he does say " The truth is, the currents always seek out the lowest resistance path..." but fails to explain that the wire is what adds resistance, so if you connect to one battery and the current has to pass through wires to get to other batteries there is more resistance.

    Here is a link that explains how to set up multiple strings for equal resistance;

    Multiple string will always be more trouble than a single string, once they get out of balance, there becomes easier and harder paths for the current to flow. Batteries are 2 volt cells, a 12 volt battery is just a string of 6 2v cells. As @softdown ; and @mcgivor ; have suggested a single string of 2 volt cells eliminates the worries of parallel strings of batteries. You can also find large traction batteries typically used for forklifts that are made up of a string of large 2v cells, but they are very heavy.

    Specific gravity is the only way to determine the true health of a battery. Get a hydrometer and learn to use one. Wattage above the panel rating isn't uncommon in 'edge cloud' events and momentary instances. Typically panels will produce about 75% of their panel rating once they are hot...
    That link is so sneaky. Those are all 12 volt battery configurations. I went to use it on my newest 48 volt bank before that discovery. It was pretty embarrassing at the time. That link either fooled everybody or people sure kept silent.

    24 volt forklift battery would be a good choice if you have the ability to replace a bad cell. Most do not. Hence......2  volt cells would be a great choice.
  • Re: Frigidaire on modified sine power

    Estragon said:
    In a sense, the fridge may be "weaker". The compressor just moves heat from inside the fridge to outside. The compressor itself is likely not affected by the MSW, but the motor, generally packaged with/near the compressor, will likely be heating more. Depending on how and where the compressor disipates heat, the extra heat from the motor may also have to be overcome.

    Good to know you don't have to lug the thing in for repair. My cabin is also water/ice access, and I know how much of a PITA that can be.
    FWIW and more technically speaking.....refrigeration compressors are "removing energy". Heat is energy. 

    Speaking of which, I have to go look at my BP panels before they have absorbed too much energy.
  • Re: Cable Connections: Battery Bank

    mike95490 said:
    Isn't everything SUPPOSED to be big in Texas ?  Big Freezers.  Big Solar Arrays
    I'll not forget the time I celebrated two birthdays while crossing Texas.

    Houston is hot and humid. West Texas is hot and dry. El Paso and San Antonio are slightly more than hot.

    You really have to live there to understand Texas pride.
  • Re: Help me fix this blokes jerry rigged system?

    This may work:
    400 watt panel = 40 volts
    4 x 150 watt panels into parallel and serial so = 40 volts
    3 x 100 watt panels all paralleled so = 20 volts
    Total voltage = 100 volts

    Why not?
  • Re: 36 volt Forklift battery

    BB. said:

    Also, some (few, many, all?) forklift batteries may need the metal case/support for their cases (relatively thin wall).

    Duct tape

    Seriously....hardware store carry 250' rolls of 3/4" thin steel for hanging conduit etc.

    I'd make a 24 volt and a 12 volt battery out of it.