Just bought a smartsolar 100/30
When I hook up the PV wires which are reading 19V
It shows in the app as just over 12V.
Is this because the battery is full and it is keeping the system off by not showing it 5V higher than my battery voltage??
Just confused why it is not showing the same as my multimeter.
Are you Measuring the 19V with the MPPT beeing connected, or without?
If without, then you are Measuring the Open Circuit Voltage of the panel, which is higher than with a connected MPPT.
In that case, it may be very likely that the MPPT is pulling the voltage down and therefore not reaching BAT+5V as you assume.
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Yes- measuring the ends of the wires coming down from the panel before I plug them in- I get 19v
After they are plugged into the MPPT the app shows the PV solar input at 12v.
That is a normal-expected drop?
And if that is true- it would mean my battery has to drop to 7V before charging is triggered?
That does not seem correct to me…
19V is a pretty low open circuit voltage (Voc)
Your MPPT can handle up to 100V on the PV side, thats what the first number stands for. If you have a single panel, then theres not much you can do. If you have panel i parallel, then consider rewiring them for series
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VOC (voltage open circuit) is not the same as voltage under load.
19voc is not high enough to start charging a 12v battery with an mppt. You will need a pwm controller instead or more solar panels.