I have captured a voltage spike that is greater than 16vdc on the battery terminals of the MPPT when it transitions from Bulk charging to Absorption charging. This voltage spike puts my inverter into protection mode and sets the high voltage alarm. The unit has been working flawlessly for over 2 years. It is setup using factory default. Has anyone else experience this? Purchased new in June 2023.
Batteries: I have 2 Lifepo4 12v/100Ah wired in parallel
@mkvictron it sounds like the battery BMS is disconnecting the cell from the battery terminals for a short period. If the battery was connected to the output of the regulator it couldn’t spike to 16 volts. The internal resistance of the battery wouldn’t allow it.
The Inverter is seeing >16v for a brief msec and initiates the hi voltage alarm. It seems more probable that the mppt is leaking pv voltage (22v) to the batteries during the transition from bulk to absorption.
I’m not seeing alarms or errors on the batteries bms.
If the BMS suddenly blocks charging due to a high cell voltage that can result in a short voltage spike because the MPPT can’t stop charging immediately.
I’ve identified 4 more peculiar things with the mppt
It will also voltage spike (but not as high) when transitioning from absorption to float mode.
It allows me to turn on Expert mode, but does not allow me to change any settings. They are all grayed out. No, the setting lock is not enabled. It is v1.68, the latest version.
I don’t believe the levels recorded in Trends are accurate, meaning I don’t believe they capture the true max or min value.
When viewing live data I can see the voltage spikes, and screen shot them. But the scale changes when I return a few minutes later. The top scale value of 15.22 v (live) changes to 14.71 v (stored).
