I have an issue with my 250/60-tr MPPT, which is connected up to a 12volt system utilising 800 watts of panels (4 x 200w). Once the solar input gets to a certain point, say over 500 watts the input drops to zero and then slowly climbs back up. It does this over and over. We had this problem previously and thought we had fixed it with a change of circuit breaker however it has now returned. I have changed out the circuit breaker but it has reverted back to doing it.
I have checked all of the connections and the panels individually .
Is it a firmware issue or am I missing something
Any ideas??
Pete
It would be good to see the battery voltage and current at the same time.
As the measured PV voltage is increasing it looks like it is not a problem on the solar panel side.
One problem could be an intermittent loose connection or fault on the battery cabling such as a poor breaker, or the BMS disconnecting if lithium if one of the cells is out of balance. If it is this, the measured battery voltage at the MPPT will increase when the PV voltage increases.
Not sure about firmware, if it is this, the measured battery voltage at the MPPT will decrease when the PV voltage increases.
A multimeter may help diagnosis.
I will have a look tomorrow during the day when I have some sun and can check battery voltage.
I have a second set of panels running thru an identical mppt and the same overall circuit breaker. They are behaving normally.
I may swap the mppts over and see if the problem persists.
The reason I made the comment about the firmware was the attached post which has the identical symptoms and seems was solved by going back to an older version of firmware.
