Grundfos ALPHA Solar 25-75 180mm

The new ALPHA SOLAR is designed to be integrated in all kinds of thermal solar systems with either variable (matched-flow) or constant flow rate. High-efficiency ECM (Electronically Commutated Motor) pumps, such as ALPHA SOLAR, must not be speed-controlled by an external speed controller varying or pulsing the supply voltage. The speed can be controlled by a low-voltage PWM (Pulse Width Modulation) signal from a solar controller to optimise the solar harvesting and temperature of the system. As a result, the power consumption of the pump will be reduced considerably. If no PWM signal is available, ALPHA SOLAR can be set to constant speed, only switched on and off by the controller.