Hello! I'm hoping I can get some help with my low charge current issue. Please understand, this is my first solar setup/major electrical project and I've laid out the info the best I can. I'd like to be a big academic sponge to soak up any input or opinions about my situation.
I have a MPPT charge controller/inverter all-in-one (PIP 2724 LV) connected to 2-12.8V 280AH batteries in series for a 24V system. I am currently building out my van and have nearly the exact same solar setup recommended in the charge controller manual.
CHARGE CONTROLLER PV SPECS:
RECOMMENDED PANEL SETUP:
MY CURRENT PANEL SPECS:
My current panels have almost the exact same specs as recommended and it recommends 3 panels in parallel. I AM PART WAY THROUGH THE INSTALLATION AND HAVE 2 PANELS INSTALLED IN PARALLEL. I will be adding the 3rd but I strongly believe that is not part of my problem--->
PROBLEM:
Immediately after I pull the van out of a cool, shaded area and into the sun nearly directly overhead, completely clear day, 80 deg F, The charge current is ~12A which makes sense to me as 2 panels with 8.27Pmax current in parallel = 16.54A. Introduce real-world variables and 12A seems ok.
Over the next hour or so, the PV current and wattage continue to slowly decrease to 3.5-4A and 105-108W which is very far off from the theoretical 16.54A and 500W output.
After the panel reading have dropped, The charge controller is reading the panel voltage at 30V, which matches the same reading I get with the panels disconnected and measured at the controller, with a multimeter. My understanding is that the open circuit voltage SHOULD theoretically be closer to 37.6V.
CONJECTURE:
Looking at the PV voltage range of the controller (30-50V) and my panel measured voltage (30V), I am damn low, if not off the charts on the bottom end of that range. In addition, my battery voltage is 26.2V with the inverter off for no power draw, which is very close to the 30V panel voltage.
Is the voltage drop caused by the panels warming up in the sun dragging my voltage too low for the charge controller to effectively charge the batteries? Are the voltage differences between the panels and the batteries too low for a powerful charge? If so: Why the F*%# would they recommend a panel setup that would supply a voltage that is so close to the lowest recommended voltage value?
If I understand correctly, adding the 3rd panel in parallel will not affect the output voltage. If my assumption of the problem is correct, How would I fix this problem/boost the voltage? Id hate to scrap these panels.
Tomorrow I will check the panel output wattage and voltage while the panels are still cool to see if that helps me understand the issue.
Thanks for any help!
I have a MPPT charge controller/inverter all-in-one (PIP 2724 LV) connected to 2-12.8V 280AH batteries in series for a 24V system. I am currently building out my van and have nearly the exact same solar setup recommended in the charge controller manual.
CHARGE CONTROLLER PV SPECS:
RECOMMENDED PANEL SETUP:
MY CURRENT PANEL SPECS:
My current panels have almost the exact same specs as recommended and it recommends 3 panels in parallel. I AM PART WAY THROUGH THE INSTALLATION AND HAVE 2 PANELS INSTALLED IN PARALLEL. I will be adding the 3rd but I strongly believe that is not part of my problem--->
PROBLEM:
Immediately after I pull the van out of a cool, shaded area and into the sun nearly directly overhead, completely clear day, 80 deg F, The charge current is ~12A which makes sense to me as 2 panels with 8.27Pmax current in parallel = 16.54A. Introduce real-world variables and 12A seems ok.
Over the next hour or so, the PV current and wattage continue to slowly decrease to 3.5-4A and 105-108W which is very far off from the theoretical 16.54A and 500W output.
After the panel reading have dropped, The charge controller is reading the panel voltage at 30V, which matches the same reading I get with the panels disconnected and measured at the controller, with a multimeter. My understanding is that the open circuit voltage SHOULD theoretically be closer to 37.6V.
CONJECTURE:
Looking at the PV voltage range of the controller (30-50V) and my panel measured voltage (30V), I am damn low, if not off the charts on the bottom end of that range. In addition, my battery voltage is 26.2V with the inverter off for no power draw, which is very close to the 30V panel voltage.
Is the voltage drop caused by the panels warming up in the sun dragging my voltage too low for the charge controller to effectively charge the batteries? Are the voltage differences between the panels and the batteries too low for a powerful charge? If so: Why the F*%# would they recommend a panel setup that would supply a voltage that is so close to the lowest recommended voltage value?
If I understand correctly, adding the 3rd panel in parallel will not affect the output voltage. If my assumption of the problem is correct, How would I fix this problem/boost the voltage? Id hate to scrap these panels.
Tomorrow I will check the panel output wattage and voltage while the panels are still cool to see if that helps me understand the issue.
Thanks for any help!