Just installed a MPPT 75/15 controller connected to a Renogy 200w portable panel and a Battle Born 300Ah battery bank. I’ve tried rebooting and have checked the 20A fuse on the controller, checked all connections and the breaker between the controller and the batteries.
The app as well as my meter readings are showing 19.5 - 20.5 volts coming from. the solar panel. The app is showing the battery output at 13.49V and the controller has cycled from bulk to absorption to float state. I’ve never seen anything but 0.0A current from the panel or to the battery. All my settings on the controller app are as directed by Battle Born. My shunt is currently reading 78% SOC and 13.13V.
I did the firmware update initially when I set up the app.
The MPPT doesn’t strt untill the PV voltage is 5V above the battery voltage, however, as the unit looks like it has started and cycled through to float, this isn’t the issue.
From the battery voltage, it looks like the battery is near full charge, so won’t accept more charging in bulk mode.
For more help, please post your actual MPPT settings.
please can you post the settings: find the cog at the top and then battery?
While it is not unusual to have some discrepancy between the voltages reported by the mppt and the bms, do you have any fuse or other switch between the MPPT battery connections and the battery?
Absorption Voltage 14.4
Float voltage 13.5
Equalization voltage 14.4
I have a rotary battery disconnect switch between the MPPT and the battery. Also a 20A manually resettable breaker. Before turning the system on, I checked continuity of all components and connections with a meter.
At this point, I feel as though I’ve checked everything and have dedicated way too many hours to what appeared to be a simple project. I’m working under the assumption that this unit has some defect out of the box and have a replacement coming tomorrow.
Ok, so the indicated float voltage matches the set float voltage. There is also a battery fuse on the unit, close to the battery terminals. If this is accessible - some are internal - then you can check the volt drop across the fuse.
Also you need to check the volt drop from the B- terminal of the mppt to the battery - terminal, and likewise on the positive side - with the unit on. You are looking for an open circuit somewhere.
