Johann ✭✭✭

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Johann
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  • Re: Ground Wire in My Shop?

    Estragon said:
    Maybe a bigger question is what you intend to run with a 2500w inverter off a couple of small 6v batteries. That's a lot of current at 12v from batteries that aren't made for it.
    Those high wattage inverters are great to start inductive loads and a necessity in some cases to start motors. The higher amps may only be needed for a few seconds. A high wattage inverter does not indicate that a user will max it out.
    Remember, the OP mentioned that it is being used in a  workshop so more power may be required for a few seconds at start-up where a smaller inverter may kick out.


  • Re: Battery pulling down panel voltage???

    What I am working with (For now):

    1.) 2 100 watt panels wired in parallel 25 feet from charge controller using 10 AWG wire.

    2.) Morningstar TriStar PWM 60 set for 12 (14.6) volts, 4 feet from batteries using 2 AWG cable.

    3.) 2 new DEKA group 31 flooded batteries fully charged before use (210 AH total).
    ...........
    My question is, 1) is it normal for a discharged battery to pull the panel voltage down below my setpoint of 14.6 but leave the amps full throttle? I am new to this and this is my first run after much research

    If that is normal, that tells me 200 watts of solar power is not nearly enough to charge a 210 AH battery bank. 2) Am I right?  3)Will more panels bring the voltage up to charge faster?


    1) Yes 2) Yes 3) Yes
    When a battery is well depleted it will take a long time for the amps to get high enough that the volts starts to rise.  When there is enough internal resistance to the Amps available the volts will start to rise and you will enter Absorb phase.  This is a lesson in what you get without enough panels...  it may take several days for your batteries get filled... You could figure out the number of watts or Ahrs of power you ahve used and then use 4 hrs of good sunshine per day  to estimate how long the recharge will take... But in the mean time go out and find 2 more identical panels.... to add to the setup.hth
    I probably did more research than a lot of newbies do but I'm still getting spanked! Lol I had already set my mind not to expect too much from a solar system within my budget. I know for example those aren't the best batteries to use, but I figured if I ruined them it's better than ruining some Trojan batteries.

    Thanks so much for your reply!


    Nobody is going to spank you here, just good ole folks trying to help you and trying to protect your equipment so it will last longer.

    The better way to check the state of charge is after the battery been sitting for a few hour without charging or discharging the battery. This way the surface charge on the plate is dissipated and you will see a truer state of charge.

    200 watt of solar panels, will still give you enough power for LED lighting at night or in emergencies and power for other small electrical items/things as long as you watch your power usage a bit.
  • Re: charging a second battery bank , with dump load from a pmw

    mike95490 said:
    Remember, the dump load is critical, and prevents either/both the batteries being overcharged or the turbine spinning unloaded and disintegrating.  A 100 gal water would be a minimum load, and remember, after 3 hours and the tank is hot, the thermostat goes off and you loose your dump load.
    Mike, the turbine stays connected to the battery at all times, so it always stays ''loaded'' even while the controller is dumping power. The controller is dumping power from the battery to a resister which is heating up when dissipating power in a normal ciurcuit. The turbine never gets disconnected from the battery while that is happening.

    When the thermostat goes off a second controller can dump that extra power into a resistor.


    If the battery need to be disconnected at a point for maintenance for example, there should be a switch installed that will short circuit the 3 phase ac side at the rectifier, this will put a load on the turbine and act as a break.
  • Re: charging a second battery bank , with dump load from a pmw

    Consider yourself lucky if you live in a place where you have strong usable wind to actually make power. Many places have wind, but not enough wind to make  power.
    Basically, wind power stays connected to battery #1 at all times. If your battery #1 is full then the controller #1 is connecting a load/resistors #1 to the battery #1 while your wind power stays connected. This will draw power from battery #1.
    Your load/resistors #1 could be a battery or let's call it battery # 2.  If battery # 2 gets full you need a controller #2 to dump power into your resistors to avoid over charging battery # 2. 
    If using a inverter at any battery then a low voltage shut off should be incorporated, since most inverters will shut down when the voltage  is way to low and when the battery is discharged or dead which kills batteries in no time.  

    Depending, you may need to control the amps into battery #2. You may even need a charger or generator to fully charge battery #2.

    I would make battery #1 bigger and not using battery #2 , dump power into a water heater with controller #1.
    When water heater is turning off, controller #2 can dump power into the resistors or a heater in winter.
  • Re: DC - DC Battery Charging Using a Charge Controller

    It may be cheaper just to use an  24 volt/ 120 volt inverter and then plug up a 120 volt/ 12 volt power supply or a battery charger depending on the application for what it is used/needed for.