why doesn't the light bulb work?

rdickson
rdickson Registered Users Posts: 5
I've got a simple solar streetlight that I installed back at the end of May. It's got a 45 watt PV panel hooked to a xantrex c12 controller, with a sunextender 42ah battery as storage.
The load is a 5 watt LED bulb in a glarebuster fixture.

When I hooked everything up on 5/27/11 everything worked perfectly. The battery charges to float level every day, and the light came on near dark and stayed on all night.

I noticed a few days ago that the light wasn't on, and moreover, that the xantrex was blinking orange. I think that means an overload condition, but I'm not sure.

So I swapped out the 5w bulb for a 1 watt, which is all I had, and it worked fine. The xantrex light went back to green.

When I test the 5 watt bulb with a direct battery connection, however, it works fine.

Can anyone "illuminate" me as to what's going on here?

thanks,

Robert Dickson

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: why doesn't the light bulb work?

    From the C12 manual:
    Dusk-Dawn Operation
    If the NITE-LITE-TIME knob is turned fully clockwise to the area
    marked D-D, dawn to dusk operation will be selected. This allows the
    lights to operate all night, turning on at dusk and off at dawn.
    If the voltage falls below the LVD setting for more than 2 minutes, the
    lights will be turned off to prevent damage to the battery. The LVD will
    be reset once the charging process increases the voltage above the
    LVR setting, usually during the next day. No warning flash will occur
    before the lights are turned off when D-D mode is selected. In D-D
    mode the run time is limited to a maximum of 20 hours.

    Testing the Lights with the Reset Switch
    Pressing the reset switch in NITE-LITE mode allows testing of the
    lights. They will be turned on even if it is daytime or if the controller
    has disconnected the lights due to a low voltage condition. This is
    intended to allow easier troubleshooting of systems in the field.
    ....
    • Slow Blinking Orange—The C12 has disconnected the loads
    due to reaching the LVD setting. The user can press the reset switch
    for a one time 10-minute “grace” period or can wait until the voltage
    rises above the LVR setting to allow a manual or automatic reset to
    occur. If manual reconnect was selected, the loads will not resume
    operation until the reset switch has been pressed.
    • Fast Blinking Orange—The C12 has detected a short circuit
    and has disconnected the loads. The C12 will try to automatically
    restart the loads after a 12-second delay. If the loads will not restart,
    turn off all loads and press the reset switch. If the C12 then restarts,
    the loads may be too large. Up to a 12 second delay may occur
    before the C12 attempts to restart after pressing the reset switch.

    Fast/Slow blinking Orange?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • rdickson
    rdickson Registered Users Posts: 5
    Re: why doesn't the light bulb work?
    =Fast/Slow blinking Orange?

    that's really the question. I have essentially no experience with these controllers, but based on the way the green lights flash as the battery charges, I'd have to say the orange lights are flashing slower rather than faster.
    This would indicate a low voltage disconnect according to the manual, but when I remove the load ( or replace it with the 1 watt bulb), the xantrex light glows steady green indicating it's reached float voltage.
    I really don't understand what has changed to cause this to happen.

    Robert
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: why doesn't the light bulb work?

    Have you measured the battery voltage? Battery problems (sulfating, loss of water, etc.) or corroded/dirty/failed wiring connections could cause what you are seeing...

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • waynefromnscanada
    waynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: why doesn't the light bulb work?

    Have you checked the actual voltage on your battery when the orange light is flashing? Are the connections at the battery corroded and/or poor and not making proper contact? While under load, check the voltage at the actual posts of the battery, then check the voltage on the wires coming from those posts. Good clean connections will result in the meter showing the same voltage. Bad or poor connections (under load) will show a voltage difference. Likewise, a poor connection at the battery could trick the controller into "thinking" the battery is up on full charge when trying to charge the battery, while when taking power from the battery, could make the battery look discharged when it's really not. OR, it could be that the battery is just no more good, has lost all, or very nearly all it's storage capacity, nothing will go in, so it looks charged / nothing will come out, so it looks discharged.
  • waynefromnscanada
    waynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: why doesn't the light bulb work?

    Sorry BB, didn't see your post until I hit SUBMIT.
    But great minds do think alike :p
    Our first thoughts are not with the controller.
  • rdickson
    rdickson Registered Users Posts: 5
    Re: why doesn't the light bulb work?
    Have you checked the actual voltage on your battery when the orange light is flashing? Are the connections at the battery corroded and/or poor and not making proper contact? While under load, check the voltage at the actual posts of the battery, then check the voltage on the wires coming from those posts. Good clean connections will result in the meter showing the same voltage. Bad or poor connections (under load) will show a voltage difference. Likewise, a poor connection at the battery could trick the controller into "thinking" the battery is up on full charge when trying to charge the battery, while when taking power from the battery, could make the battery look discharged when it's really not. OR, it could be that the battery is just no more good, has lost all, or very nearly all it's storage capacity, nothing will go in, so it looks charged / nothing will come out, so it looks discharged.

    battery (and wiring) was new in May and shows 13.4 across the posts, 13.3 under 1 watt load.

    I couldn't get the 5 watt bulb to give the orange blinking light today, and it wouldn't light when hooked directly to a battery either. So I unscrewed the base and found a loose wire. My assumption is that wire was shorting somehow and causing the error, but that could easily be wrong.
    I really can't find any fault with this almost-new system.

    thanks for all your help, and if my assumption about the bulb seems wrong, please say so.

    robt
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: why doesn't the light bulb work?

    The charge controller is probably limited to 8-10 amps or so. A short on in the base of the bulb is certainly a possibility.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset