Solar panels
List of known issues and resolutions.
Limited battery capacity [INC-SOL-003]
Discovery date : 01/01/2018
Criticality : medium
Impact : all greenhouses equipped with a solar module.
Description of the incident :
The batteries discharge very quickly off-grid.
Cause : Maintenance issue with the batteries.
Resolution : Depending on the model, it is essential to top up demineralized water in each battery cell. There are 6 positions per battery.
Overcharged batteries [INC-SOL-004]
Discovery date : 01/03/2020
Criticality : medium
Impact : all greenhouses equipped with a solar module.
Description of the incident :
The batteries have overcharged: the output is disabled for safety reasons.
Cause : Incorrect wiring, faulty contact between the terminals, demineralized water level in the batteries too low.
Resolution : check the demineralized water level in all battery cells, top up if necessary. Disconnect for a few moments the + wire between the batteries and the MPPT and the + wire between the solar panels and the MPPT. Once the MPPT is off, reconnect the battery + wire and then the solar panel + wire to the MPPT. By moving through the MPPT menu, check that the battery voltage is correct and that charging via the panels is effective.
Batteries not charging in full sun [INC-SOL-005]
Discovery date : 01/03/2020
Criticality : medium
Impact : all greenhouses equipped with a solar module.
Description of the incident :
In full sun, the panels deliver a voltage of 24V, which is not enough to charge the batteries.
Cause : Incorrect wiring during installation, panels connected in series instead of in parallel.
Resolution : Connect the panels by following the instructions in the assembly manual.
Batteries in deep discharge [INC-SOL-006]
Discovery date : 01/04/2020
Criticality : high
Impact : all greenhouses equipped with a solar module.
Description of the incident :
After the power box update, the voltage across the battery terminals is sometimes below 20V. In their standard charging mode, the battery operating range is between 24 and 30V.
Cause : Electrical board behavior (old version), lack of demineralized water in the battery cells.
Resolution : Top up demineralized water in the 6 cells of each battery. Use a battery charger in 12V mode. Remove the fuse from its slot in order to charge the batteries one after the other. Connect the two terminals to the charger. Plug the charger into the mains and press "Reset". Start the charger and wait until the needle shows that the battery is fully recharged. The operation may take several hours depending on the discharge level. Repeat the operation for the second battery. Once charging is complete, reinstall the fuse. At that point, the MPPT may display an error message for overcharge. Disconnect for a few moments the + wire between the batteries and the MPPT and the + wire between the solar panels and the MPPT. Once the MPPT is off, reconnect the battery + wire and then the solar panel + wire to the MPPT. By moving through the MPPT menu, check that the battery voltage is correct and that charging via the panels is effective.
Disconnecting the fuse
Connecting the charger
Checking the operating status of the batteries after the operation
The battery level and available solar power can be accessed from the MPPT controller located inside the power box.
[Diagnostic] Checking panel operation
MPPT screen of the device operating inside the power box
It is possible to check that the panels are operating correctly on the MPPT:
- PV : between 30 and 42V (depending on the sun) ||| 24V in full sun means there is a wiring problem.
- BATT : between 24 and 32V (depending on the charge) ||| less than 24V means there is a wiring problem or deep discharge.
- LOAD : active, when there is no malfunction on the panels or the batteries.
Next, the status of the LEDs on the front of the power box indicates the type of power supply mode.
[Diagnostic] Batteries not recognized by the MPPT controller
To check battery operation, a voltmeter / multimeter can be used at the MPPT to check the available voltage.
If no voltage is measured, check the battery connectors, the condition of the fuse, and the demineralized water level inside the batteries.
[Diagnostic] MPPT controller user manual
To diagnose the condition of the solar module more easily, it is useful to refer to page 24 of the manual.