diy solar

diy solar

Battery battery voltage fluctuating after float voltage.

Mickie

New Member
Joined
Feb 24, 2022
Messages
213
I have a 40A solar charger. "Mppt solar charge controller" the float charge is set to 13.7 but when the battery is full on the charger 13.7 is displayed but the inverter is fluctuating even going up to 15v. Is a faulty charge controller?
 

Attachments

  • 20220516_084104.jpg
    20220516_084104.jpg
    165.2 KB · Views: 6
  • 20220516_084111.jpg
    20220516_084111.jpg
    141.3 KB · Views: 6
The "MPPT solar charge controller" is a fake. It is not MPPT, it is PWM.

Have you confirmed all voltage readings with a separate meter?

Have you confirmed that all wire is of appropriate gauge?

Have you confirmed that ALL connections are secure and properly torqued?
 
The "MPPT solar charge controller" is a fake. It is not MPPT, it is PWM.

Have you confirmed all voltage readings with a separate meter?

Have you confirmed that all wire is of appropriate gauge?

Have you confirmed that ALL connections are secure and properly torqued?
Ok but being as it is a pwm shouldn't it still stop the charge at 13.7?
Yes I have checked the readings with a multimeter. The battery is behaving as if it's connected to the solar panel directly the voltage keeps going up and down but when the panel is removed from the charge controller the battery is stable at 12.7
All wires seems to be ok.
 
As with the previous charge controller giant of sun solar controller it stopped the charging at the float voltage but when the battries dropped back to 12.6 it would not restart charging. That is why I tried this one but seems there is a issue with this one or am I not doing something correct
 
Ok but being as it is a pwm shouldn't it still stop the charge at 13.7?

Yes

Yes I have checked the readings with a multimeter. The battery is behaving as if it's connected to the solar panel directly the voltage keeps going up and down but when the panel is removed from the charge controller the battery is stable at 12.7
All wires seems to be ok.

Cheap, fake "MPPT" PWM controller not only lies on the markings but on the voltage as well. Replace with something reputable.
 
Back
Top