Connecting a 48 volt Zephyr fan directly to battery bank?

midijeep
midijeep Registered Users Posts: 102 ✭✭✭
edited May 2018 in Solar Beginners Corner #1
I had an automatic transfer switch installed with my SMA Sunny Island/ Sunny Boy system.  I was using the "BatVtgOut" off the circuit board to power the Zephyr Battery Box Ventilator at 48 Volts DC.  I now need to power the fan off the battery bank directly.  The battery bank is 200 Ah at 48 volts.  Can I directly hook up the fab to the battery bank?  I am not sure because the battery bank is rated at 200 Ah.  Or do I need to put something in between the fan and the bank to handle the 200 Ah's?

Comments

  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    The fan will only use what it needs so connection to the battery would not be an issue, some form of control between the two would be advisable, for example to run only when the battery voltage exceeds a certain value turning off when under, to prevent running when not nesesary.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • midijeep
    midijeep Registered Users Posts: 102 ✭✭✭
    mcgivor said:
    The fan will only use what it needs so connection to the battery would not be an issue, some form of control between the two would be advisable, for example to run only when the battery voltage exceeds a certain value turning off when under, to prevent running when not nesesary.
    Sound advise.  I do have two built in relay's on the Sunny Island but I am not ure how to wire the fan now to one of the relays.  The relays have NC, C and NO to wire to.  The only thing I have is showing hiw to wire the battery fan using the "BatVtgOut" and "Relay" (see attachment.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    There is installing a circuit breaker in the wiring of a couple amps.

    Fuses and breakers are there to protect the wiring and devices from fire.

    AWG of wiring sized to carry current for the fan (at least 1.25x fan rated current). Probably something like 2-5 amp wiring and fuse or breaker.

    Your battery bank can output 100's of amps into a dead short.

    Always worry and plan for safety.

    Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    The load shedding contactor is a slave powered by the battery voltage sourced internally, it may be wise to run a relay in the same configuration powering the relay coil and run the fan through a NO contact powered directly front the battery through a fuse, of the slave relay. The DC output may have limited capacity, typical on other inverters/controllers.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Fan only needs to run when batteries are charging.  If it does not consume too much power, you can run it 24/7, but expect replacements every couple 3 years.   Or a fan with it's own little PV panel, no battery.  You  have to test to make sure fan will start off the solar panel.
    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 ,

  • midijeep
    midijeep Registered Users Posts: 102 ✭✭✭
    mike95490 said:
    Fan only needs to run when batteries are charging.  If it does not consume too much power, you can run it 24/7, but expect replacements every couple 3 years.   Or a fan with it's own little PV panel, no battery.  You  have to test to make sure fan will start off the solar panel.
    For now I think i'm going to keep it wired directly to the battery bank with the positive fuse wiring that came with it .  I'm going to look into how to wire the relay in the sunny island and use the battery bank as the power source. Looking at the schematic I attached earlier. I'm not sure how to wire the fan with the relay and using the battery bank as the power source.

    Side note:
    I happened to have two Zephyr's, where one was brand new and the other one that was hooked up went out.  I went ahead and hooked up the new one to the battery bank and the one that went out I took apart.  One of the fans positive lead disconnected from inside one of the 24v fans.  I ordered new fans to replace the 3 year old Zephyr .  Total cost was $20.  I ordered extra fans for the future.  The 48 volt Zephyr has two 24 volt fans connected in series.  Seems that the $110 for the Zephyr's have a huge mark up.  Not now.




  • NANOcontrol
    NANOcontrol Registered Users Posts: 260 ✭✭✭
    There are $10 low voltage detectors available.  The electable voltages are a little low. If you take a number of diodes in series to supply the power to the module, it can raise the voltage by about 0.6V each.   That will give you an easy detector of when the batteries are charging and turn on the fan.