Hi everyone,
I have a narrowboat and have fitted a solar panel. It's been on for about a week and a half.
My setup is a single 250W, 48V Voc, panel connected to a Victron 100/20 smart solar MPPT which in turn is connected to my 3 service batteries.
The MPPT updated firmware a couple of times before I turned the system on and the battery values are Victron default.
The MPPT is in the engine bay about 8 inches from the battery box so no temperature sensor is needed. The original installation includes a Victron Phoenix multiplus 3kW inverter, currently switched off, and a BMV-501 battery monitor.
When I first switched the panel on it was facing slightly away from the sun and it showed 125W and 9 amps into the batteries which I thought was quite good.
I left the fridge on for a couple of days to load the batteries and see how much the solar helped. After the 2 days the battery monitor showed the batteries at 82.4% and the overcast weather had just started so I switched the fridge and all other loads off expecting the panel to charge the battery.
However for the last 4 or 5 days the BMV501 has shown a constant 82.4% and the solar shows something like 3W and virtually no current into the batteries. I know there won't be much power produced with it overcast but yesterday whilst the solar showed 3W the sun came out but the panel showed no increase in power. It did show an increase in panel voltage so it registered a change.
All the time the panel is on it is producing 13.67 Volts across the batteries and is showing float mode. The load output is set to 'always off' since I have no load to connect. The BMV-501 battery voltage agrees with the smart solar app.
Today was much sunnier so I checked the panel but it was showing much the same values. I then turned the panel off and the BMV-501 showed a battery voltage of 13.32 Volts but still 82.4% charged.
I have a picture of the BMV-501 before solar installation showing a battery voltage of 12.88 Volts when it is indicating 100% charged.
So it looks like the MPPT thinks the battery is fully charged and refuses to put any charge into
the battery but my BMV-501 thinks it is only 82.4% charged.
Does anyone have any advice please?
