Function and structure of the power supply unit

Control systems are supplied with power via the electrical network. The MecLab® controller has a power supply unit for this purpose (see Figure 3.15). The individual modules of the power supply unit have the following purposes:

• The transformer serves to reduce the operating voltage. The mains voltage is applied to the transformer inlet (e.g. 230 V AC), the voltage at the outlet is reduced (e.g. 24 V AC).

• The rectifier converts the AC voltage into DC voltage. The capacitor at the rectifier outlet serves to smooth the voltage.

• The voltage regulator at the power supply unit outlet is necessary to keep the electrical voltage constant irrespective of the flow of current.