I have a problem that I can't wrap my head around. I have a SmartSolar 150/100 MPPT that has been configured for 12v. I recently purchased a 48v inverter and reconfigured my 12v battery bank to 48v.
I am seeing really strange behavior in the MPPT charger. The unit will bulk and absorb charge fine most of the time, but it will not put any current into the battery when it switches to float mode and the voltage drops well below the float setting.
Sometimes in the morning when the unit starts up for the day it wont charge while in bulk mode. The MPPT controller did this again today. My battery voltage was at 51v and I had 75v on the Panels. I went into the charger settings via bluetooth and disabled and re-enabled the unit and it started charging in bulk mode again.
I have been fighting this for about 2 weeks now and don't know which direction to go.
I am wondering if I don't have enough PV voltage for the unit to function properly. When configured for 12v I had 2 panels in series which was around 50 volts. With the 48v battery configuration I only added 1 more panel in series for a total of 3 panels in series which gives me 75v. I could add a 4th panel to the series string but would rather not at this time. I have 9 200w panels and would like to do 3s3p, I hope that's how to say that.
I have SOK rack batteries ordered so the bulk mode will be set too a lower voltage, which I hope will give me a little more head room with the 3 series strings.
Also when I switched over to 48V there was a firmware upgrade. The MPPT is now at v3.07. I did some searching and could not determine if that is actually the latest version of software. When I hit search for update it says the software is up to date.
I hope I didn't fry the unit when I hooked up the positive lead of the battery connection it sparked and popped. I did not think to use a resistor to charge the caps.
I always connect the pv panels last when powering up the unit and disconnect the pv panels first when powering down the unit.
I do have the MPPT hooked to a RPI via ve.direct connection, I don't think this is the problem. I have disconnected the PI with no luck.
I am also wondering if it just takes time for the unit to get use to the new setup, in the manual I think it states it takes 5 days for the unit to calculate its power curves.
My settings:
Thanks for all the help!
Nick
I am seeing really strange behavior in the MPPT charger. The unit will bulk and absorb charge fine most of the time, but it will not put any current into the battery when it switches to float mode and the voltage drops well below the float setting.
Sometimes in the morning when the unit starts up for the day it wont charge while in bulk mode. The MPPT controller did this again today. My battery voltage was at 51v and I had 75v on the Panels. I went into the charger settings via bluetooth and disabled and re-enabled the unit and it started charging in bulk mode again.
I have been fighting this for about 2 weeks now and don't know which direction to go.
I am wondering if I don't have enough PV voltage for the unit to function properly. When configured for 12v I had 2 panels in series which was around 50 volts. With the 48v battery configuration I only added 1 more panel in series for a total of 3 panels in series which gives me 75v. I could add a 4th panel to the series string but would rather not at this time. I have 9 200w panels and would like to do 3s3p, I hope that's how to say that.
I have SOK rack batteries ordered so the bulk mode will be set too a lower voltage, which I hope will give me a little more head room with the 3 series strings.
Also when I switched over to 48V there was a firmware upgrade. The MPPT is now at v3.07. I did some searching and could not determine if that is actually the latest version of software. When I hit search for update it says the software is up to date.
I hope I didn't fry the unit when I hooked up the positive lead of the battery connection it sparked and popped. I did not think to use a resistor to charge the caps.
I always connect the pv panels last when powering up the unit and disconnect the pv panels first when powering down the unit.
I do have the MPPT hooked to a RPI via ve.direct connection, I don't think this is the problem. I have disconnected the PI with no luck.
I am also wondering if it just takes time for the unit to get use to the new setup, in the manual I think it states it takes 5 days for the unit to calculate its power curves.
My settings:
Thanks for all the help!
Nick
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