I purchased an MPPT 75/15 for a small boat system a few weeks ago. It has been working fine with two 50W panels in series charging a 40 Ah LiFePo4 battery. Updated firmware a couple of days ago and now the iPhone app stops reporting the load output about once a day. The load output is still providing power just the app fails to report it. A power cycle of the controller gets it working again. While troubleshooting this I noticed that there is now a 1.1v drop from the battery terminals to the load terminals of the controller when under a 3A load. To be clear, when battery voltage is good, say 13.2v. The voltage at the load output of the controller is 12.1v. The drop happens in the controller. Any ideas what’s going on? Thanks.
