The self-calibrating Ultraflow Smart Switch has been designed to switch the pressure controlled submersible Ultraflow Maxi Pump fitted in certain caravans and motorhomes. The inline adaptive system measures the performance of your submersible water pump and constantly adjusts the start and stop pressures to suit the water pump and battery voltage. If the water container runs dry the water pump is stopped after a short time, and the pressure switch locks out to prevent damage to the water pump until the water is refilled. Due to the integrated processor there are no adjustments to be made.