Model-Based Testing of Highly Configurable Embedded Systems in the Automation Domain

Softstarter Example

Electric motors are common actuators in process automation. For this article, the starting and the stopping of an electric motor is taken as example. The device used in this article is a softstarter as shown in Figure 1, which is used to smoothly ramp up/down a motor. This functionality is needed for large motors where the peak current consumption from the power grid may cause a breakdown in voltage or for conveyor belts where sudden steep acceleration ramps may damage the transported goods.

Figure 1.

Softstarter for different motor sizes

Besides ramping the motor up and down, a softstarter monitors the motor to detect, e.g., a locked or overheated motor or disturbances in the power supply network that might damage the motor.