After three years of monitoring my PWM system daily with a Morningstar Charge controller and becoming very familiar with the input im quite surprised at how only changing to a Victron MPPT unit changes everything .
Previously i could almost predict the Incoming charge , Voltage and Amps on a regular sunny day here in Spain would be within certain parameters , 31-33 volts and 32-36 amps , simply by changing only the Charge controller the voltages have increased to around 40v and the Amp crashed to around 20 Amps , the strange thing is that the system changes from Bulk to Absorption around the same time of day and with the same amount of Amps going into the batteries , i didnt think the batteries would charge as quickly with far less amps going in as i understood that batteries needed amps and the voltage was only the means of transporting them .
Despite the strange reversal of Volts/Amp input he Cumulative daily input has not changed at all however Charging has , before my system would go into float maybe once a week , now it enters float daily and remains there for several hours and because of the way the Victron system splits the way it displays production between Load and Charging the batteries often show less than End Amps going in and they are often shown to be Idle , previously it came close to end amps but not quite .
I bought the MPPT so that when the time came to change batteries i could use Lithium and have my panels rewired to produce the higher voltages they require , i really didn't think it would see any changes leaving them as they are . Im hoping that when winter comes this change in the charging regime works to make the system a little bit more efficient as i think it will be a while before i need to replace my bank .
