Air x battery monitoring fault.

tonygcan
tonygcan Solar Expert Posts: 91 ✭✭✭✭
Hi.
I have a 48 volt Air X turbine connected to 4-100Ah, 12 volt batteries connected in series coupled with 4- 60 watt, 12 volt sharp panels hybrid system.

Yesterday the winds were quite strong and the sun was shining and the turbine self regulated at a reading of 54.6 volts on my solar panels' CC around noontime. and for the rest of the day the Air X did not turn.

However, at around 5:30 pm as the sun was setting and I guess no charge coming from the PV panels I noticed the turbine began charging again without me having put any load into the system.

The manual says that I should connect the turbine wires to separate battery terminals to avoid the Air x's electronics from reading input from the PV panels. Could anyone explain how I should go about this? At this point both my wires from the turbine and my wires from the PV panels CC all connect to the same positive and negative terminals of my battery bank.

Do you think this could be the reason why my turbine regulates at 54 volts and not at 56.2 volts which is fhe air x's regulation factory setting?

Thanks for any help.

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Air x battery monitoring fault.

    Assuming all of your charging sources EACH goes to the +/- battery bus (i.e., the wind turbine does not go to the PV Array terminals or to solar charge controller's +/- output--Then it sounds like you are doing everything correct (appropriate fuses in each positive wire leaving the battery bank?).

    54 volts (aka 13.5 volts @ 12 battery reference). 13.5 volts is pretty much long term float charging voltage.

    One other question, what is the current from the turbine, the gauge of the wire from turbine to battery bank, and the on-way distance... In high current charging, the voltage "rise" on the wire could prematurely reduce charging current (wind controller thinks battery is higher charge than it really is). I can, or you can use a generic voltage drop calculator to see if the voltage drop will be a problem or not.

    In any case, it sounds like you should see if you can up the charging voltage set point to 58-59 volts (or whatever your battery mfg. recommends).

    I don't know anything at all about the Air-X controllers.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • tonygcan
    tonygcan Solar Expert Posts: 91 ✭✭✭✭
    Re: Air x battery monitoring fault.

    Thanks BIll. Basically, my bank is connected in series from battery 1-4. Both charging sources, wind and sun, connect individually to the batteries. Positive wires connect to positive pole of battery 1 and negative wires connect to negative pole of battery 4. Likewise, inverter wires are connected to the same poles.

    The air x manual recommends that I connect turbine wires to separate battery terminals. At this point the only viable terminals I can see connecting them to are the same terminals the PV panels CC is connected to. I think this means that the air x electronics can read the charge coming from the panels and not solely the SOC of the batteries.

    I have fuses on the positive wires leading to the batteries but not on the positive wires leaving the batteries to the inverter. Should I have fuses on those wires too?

    On the average my turbine ammeter reads 4 amps or 48 x 4= 192 watts.

    The wire from turbine to batteries is 3 wire, #6 royal cord and it runs down about 45 feet.

    The air-x does regulate when the wind is strong. It stops for a 5-10 seconds and then starts charging again. And then there are tines when it will brake and remain stopped for hours presumably because it senses that the batteries are completely charged.

    Yes I could try to increase the set point regulation voltage of the air x.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Air x battery monitoring fault.

    Your battery connections sound correct... It is what I would do (assuming I am understanding you correctly).
    tonygcan wrote: »
    I have fuses on the positive wires leading to the batteries but not on the positive wires leaving the batteries to the inverter. Should I have fuses on those wires too?
    That is the old $64,000 question.

    It is like your home wiring... How many times have you ever popped a circuit breaker--Maybe never, maybe a couple times ever?

    How likely is the inverter cabling/inverter going to short/draw excessive current? What happens if it does? Would the inverter's internal fuses open (if it has any in the DC input). Would the cabling melt and simply land on a concrete floor or land on a wood floor and start a fire in your home.

    Inverters take very large currents... A properly designed 1,200 watt wiring/breaker on a 12 volt bank would require wiring/fuse/breaker of > 168 amps (i.e., next standard breaker of 175-200 amps).

    Should you spend the $30+ on a fuse and holder (more for breaker), or not... Using a circuit breaker can be handy. Many inverters do not have an On/Off switch for their DC input.

    The answer is yes you should, but many people do not.
    On the average my turbine ammeter reads 4 amps or 48 x 4= 192 watts.

    The wire from turbine to batteries is 3 wire, #6 royal cord and it runs down about 45 feet.
    Using a generic voltage drop calculator:
    • 6 awg, 10 amp surge, 45' one way run -> 0.4 volt drop
    • 0.4 volt drop / 14.5 volt battery charging = 0.028 = 2.8% drop
    Sounds like a good setup. We aim for 3% maximum voltage drop (1% is usually the lowest that makes economic sense--price of copper cable).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • tonygcan
    tonygcan Solar Expert Posts: 91 ✭✭✭✭
    Re: Air x battery monitoring fault.

    I think I have a theory based on your posts on another thread Bill. Perhaps the turbine stops charging when it senses the batteries are full. The panels continue with the float charge. When the sun goes down and the panels no longer provide any charge the turbine cuts in and continues the float charge.

    What donyou think?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Air x battery monitoring fault.

    Tony,

    Certainly possible and would make sense if the battery charging circuitry is in the turbine instead of at the battery bank (with a dump load).

    Battery=Full; place dead short across stator (and/or mechanical brake--although, from the manual, there appears to be no mechanical brake) and bring turbine to a stop until battery charging energy is needed again.

    From the Air X manual:
    Fig. 11 represents a typical “hybrid”
    system with solar panels
    . Some charg-
    ing sources (solar panels, fuel-powered
    generators, additional wind generators,
    etc.) connected to the same system
    may cause interference with the Air X
    internal electronics and result in
    pre-
    regulation. The interference will not
    harm the turbine; it will just cause it to
    spin slowly as if “braked” or it may stop
    the turbine.
    If this occurs, test for pos-
    sible interference by disconnecting the
    other charging sources to determine
    the possible cause. If possible wire the
    turbine and PV panels to their own set
    of battery posts.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Brianellul
    Brianellul Solar Expert Posts: 95 ✭✭
    Re: Air x battery monitoring fault.
    tonygcan wrote: »
    I think I have a theory based on your posts on another thread Bill. Perhaps the turbine stops charging when it senses the batteries are full. The panels continue with the float charge. When the sun goes down and the panels no longer provide any charge the turbine cuts in and continues the float charge.

    What donyou think?

    You're right! I can observe the same behavior with my setup, in fact the turbine rarely spins in Summer thanks to the longer sunny days. If you notice the LED on the turbine, during the overvoltage stage, the LED will blink differently.