PV array output

Masterjoe
Masterjoe Registered Users Posts: 86 ✭✭
in Solar Beginners Corner #1

Ok so for some reason our installer cannot find his way to my house now and cannot come look at the system because he is "travelling".

My issue occurred in Oct of 2018. There are no system faults or warnings on the inverter or the charge controller. The inverter is registering pv output at 0.00. The system produces only .4KW per day anymore. No settings have been changed even though my installer would swear i'm touching buttons like it is an rc train set. One day it was working and the next it is not. Is there a chance the fuses located on the array burned out? There are no tripped breakers anywhere connected to the system. Our array has 2 sets of 9 panels so there would be 2 fuses out there.

4.5kw 24v System
18 Solartec 250w polycrystalline panels
Xantrex XW4024 Inverter/Charger
Conext MPPT 80-600 Charge Controller
12 Trojan L16G-AC 20 hour 390ah batteries tied in 3 strings at 1170ah total
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Comments

  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    #2

    The place to start is by measuring voltage at the combiner upstream of the fuses, there should be ~270V DC for 9 modules in series. This seems to be on the low end of the voltage parameters, if I'm not mistaken.

    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.
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,639 admin
    #3

    Can you measure the PV Input voltage at the Charge Controller when the sun is up? (somewhere in the 270+ range?

    Do you have an DC Current Clamp DMM you can measure current with?

    Is this your home or a cabin with genset--So you have been able to keep the battery bank charged and have the AC power you need?

    Somebody who knows XW products better than I should comment... But assuming nothing has changed on your system, a full power down to cold, sit for 5 minutes, then restart would seen to be the place to start.


    Assuming that it is now dark at your placer... Pull the fuses for the Solar array (you only want to pull the fuses in the dark or if blown. You do not want to pull the fuses at noon when current is flowing).

    Go in the software and shut down the inverter (bypass mode?).

    Shut down the Charge controller (pop the DC Battery breaker to MPPT controller).

    Shut down the system user interface box (LED screen).

    Open the DC breaker to the XW battery bank.

    Disconnect any ethernet cable (if you have POE or Power Over Ethernet).

    Disconnect the Can Bus (xantrex bus) from devices (comm and POE connects can prevent Com Box from shutting down completely)

    Let system sit for 5 minutes unpowered. Then reconnect com cables. Connect (turn on) battery breakers to inverter, MPPT charge controller, etc. Turn on Inverter and user black box. Reinstall fuses for solar array.

    -Bill

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    #4

    One other thing came to mind, any shading even partial on a single module in a string can cripple the output of the entire string.

    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.
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  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,917 ✭✭✭✭✭✭
    #5

    There probably is not going to be a fuse for the solar. There will be a junction box where the 2 strings combine.

    If you open the mppt meters screen, the PV input has to be over 185 volts or so to enable the device to charge. You can't do this because you do not have an scp, combox, or config tool right?

    An XW 4024 has no way to read pv volts so I am lost on what you are reading.

    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

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