DIY Knowledge

Constant-Elektronik

Electrónica constant

Régulation électronique constante

The speed of a universal motor depends primarily on the applied load. In many applications the best results are achieved by maintaining a constant rotational speed.

Sensors register the loss of speed under load and by activating a control device they can adjust the motor current in order to maintain the required speed. Often the motor current is set to less than the operating current in order to utilize the voltage difference for compensation. The above method is used,for example, for angle grinders, impact drills, planers and circular saws. A tacho-generator connected to the motor shaft acts as a sensor and transmits the actual performance value to a comparator. The comparison of actual values to desired values governs the speed electronically. Constant-Electronic is always a type of electronic regulation.

In simpler versions a top-load resistor in the operating circuit produces a load-dependent voltage drop which leads to a power boost through electronic components. (See also Types of electronic control)