New to solar - no load output

dsdurkes
dsdurkes Registered Users Posts: 1
edited August 2020 in Solar Beginners Corner #1
Hi, I am new to solar power. 
I have a 20W panel feeding a 12V lead acid rechargeable battery and trying to drive a 12v water pump. The panel fully charges the battery (checked with multimeter) but the load is 0v to the pump. I use 14 gauge wire with a maximum length of 30 feet from the controller to the pump.
I could connect the battery directly to the pump but something tells me this isn't a good idea. The controller is a TP/Solar PWM controller that came with the Panel.
Not sure what I need to do at this point and thought I'd post to folks more knowledgeable than me.
Thanks!
Don

Comments

  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Do you now the pump works?
    Are you connecting the panel directly to the battery?
    Do you know the capacity of the battery?
    The wattage of the pump?
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • InCogKneeToe
    InCogKneeToe Registered Users Posts: 73 ✭✭

    Think of it as 2 separate systems. Solar Battery Charger, and a Battery Operated Pump.

    If your Battery is fully Charged, you basically no longer need the Solar Panel, Charge Controller. Just the Battery and the Pump.

    So your problem is with the Pump or Pump Wiring. Now any 12v pump I have worked with draws 7-9amps while running. 30' of 14awg wiring might be a bit small for 7-9amps, but it should still turn the motor, of smoke trying to.

    Also, most 12 volt pumps I have worked with are "On Demand" meaning there is a Pressure Switch witch turns the pump on, and shuts it off when the desired pressure is met.

    So if the Pump is wired correctly, the Pressure switch is set correctly, the Fuse is good, the Pump should work. Again 14 gauged might be too small on a 30' run, but should make the pump twitch if nothing else.

    https://everflopump.com/wp-content/uploads/2019/06/EF1000-EF5500_manual-1.pdf



  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Welcome to the forum Don,

    As above, need to know more about your battery (12 volts @ XX AH or what)? Your pump (small pump that takes 1 amp or so for a pond pump, or an 8-9 Amp RV water pump).

    Also, how do you know the battery is charged... A battery that has "rested" for 3+ hours, ~12.7 volts or so is near 100% charged. If the battery is at 12.0 volts, that is pretty much discharged and needs to be quickly recharged.

    To recharge, you want to see the battery bus (with a small 20 Watt panel) rise upwards towards 14.4 volts or so, and hold that for 2-6 hours or so (deeper discharge, longer charge time on Absorb--holding at 14.4 volts). If you are seeing 13.x or 12.x volts during charging (and not higher), the battery is not getting fully charged.

    Debugging, put your meter on the battery terminals and turn on the pump. Your battery should be >12.0 volts with the pump running. If the voltage does not drop, then there is no or little current flow. If you see the voltage "crash" to 12.0 volts or less, then the pump may be too large (battery too small of AH capacity), or the battery is not charged, or the battery is sulfated (lead acid batteries that sit at less than ~75% state of charge for weeks/months will sulfate, and lose capacity--Basically ruin the battery).

    If you see >12 volts at the battery (pump on), then go down your wiring with the volt meter and see what the voltage is out towards the pump. You probably want >11.5 volts at the pump for good operation. If you don't see voltage, look for a bad connection. If you see 12.5 at the battery and 10.5 at the pump, your 14 AWG wiring may be too small (too much voltage drop).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Many controllers have a pair of LOAD terminals on the controller.  The terminals are often only rated for a very small load like an LED. A pump may be too large of a load for your controller.
    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

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  • littleharbor2
    littleharbor2 Solar Expert Posts: 2,039 ✭✭✭✭✭
    Late to the party buy wanted to add, Many controllers are set up to turn on loads at night, activated by the lack of solar input. They are intended for lighting circuits. Most are programable to run overnight, for a pre set number of hours, or for 24/7 operation. you may just need to set up for 24 hour operation to run the pump during daytime hours.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric,  460 Ah. 24 volt LiFePo4 battery bank. Plenty of Baja Sea of Cortez sunshine.