A solar pump controller LCB allows submersible pumps to operate earlier in the morning and later in the afternoon to extract more water form a water source or well.
It does this by boosting the available current being produced by the solar panels. The other main function of a solar pump controller is to protect the pump by avoiding sending power to the pump when there is insufficient power to power the pump which would cause the pump to "stall". They also have connections for float switches to switch the pumps off when the tank or cistern is full. Other protections include over and under voltage.
The Shurflo 9300 902-100 controller is a basic model which is used on 24v nominal solar panels and provides all the basic functions listed above. It is recommended to house the 902-100 controller in an outdoor enclosure.
The Shurflo 902-200 controller has all the features of the 902-100 and it comes in an outdoor enclosure with water level sensors and sensor wire. It can be operated from a 12V or 24V array or battery bank. It comes with Water sensors which hang in the well and are used to prevent dry running in very low yield wells.
The Aquatec controller LCB/MPPT includes over voltage sensor-less dry run protection (LWC cutout when pump runs dry and restarts automatically), pump speed control (a trim-pot that regulates the voltage to the pump motor so that you can make adjustments to water draw in low yielding wells), low voltage disconnect for 24v battey banks , ground lug terminals, and a NEMA 4 weatherproof enclosure.