mikefitz
Solar Wizard
- Joined
- May 28, 2020
- Messages
- 2,950
A PWM controller is in very simple terms a switch that connects the panel to the battery. This pulls down the panel volts to battery volts, current flows into the battery and the volts rise. When the volts exceed the charge volts setting, the PWM switch is turned off. The on and off periods are varied as the battery is charged. The frequency of switching is quite high and the pulse width of the on time is varied as required.
It's quite possible the voltage difference between the battery and panel in the off condition exceeded the design capability.
The OP has a 30 amp controller and a panel with short circuit current of 11.9 amp, it's not likely current is the issue.
The controller when operating will display charge current.
The PWM controller used and its clones is sold under different names, including Victron, but I expect the quality of components used varies.
The Victron specification states the maximum panel voltage for a 12v battery is 28 volts and suggests a 22 cell panel is used, (22 volts).
Mike
It's quite possible the voltage difference between the battery and panel in the off condition exceeded the design capability.
The OP has a 30 amp controller and a panel with short circuit current of 11.9 amp, it's not likely current is the issue.
The controller when operating will display charge current.
The PWM controller used and its clones is sold under different names, including Victron, but I expect the quality of components used varies.
The Victron specification states the maximum panel voltage for a 12v battery is 28 volts and suggests a 22 cell panel is used, (22 volts).
Mike