Solar Powered Differential Controller

For a small PV powered solar hotwater system with a small pump (20 watts or less) this solar powered differential controller is just what the doctor ordered with a price to match.   From the illustration aboveyou can see where the PV panels or DC supply connects to the controller. The pump plugs right into J1 pin 1&2. The DC power is hooked to J1 pins 3&4 and the thermistor thermistor probes are connected  to J2 pins 1,2&3 in the manner illustrated above. 

  • There is a built in protection diode incase you make a mistake and reverse polarities.

  • There is a voltage regulator that limits current flow if the probes are shorted.

  • The PVC comes with two 10K NTC thermistor probes.

  • The differential adjustment allows the user to balance heat gain with power consumption.

  • The red LED  brightness indicates the heat available for collection

  • The green LED indicates the status of the pump.

  • The solid state MOSFET relay allows the controller to remain stable at those low voltages when a pump is first activated. The MOSFET can handle a pump up to 20 watts. A battery backup is not needed with this controller.

  • The opamp is in a socket so it may be replaced easily if necessary, but should never need replacing

  • The PVC differential controller may be mounted on a wall with one screw.

  • Satisfaction guaranteed

  • FREE SHIPPING to people on planet earth only while supplies last.


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   Solar Powered Differential Controller  with probes   FREE SHIPPING in USA                                   $99