Figure 5.10 – Scheme of connecting two anti-parallel connected thyristors to the output of type С CAUTION It is recommended to connect a filtering circuit (RC) to the terminals of thyristors or triacs in order to prevent breakdown due to high-voltage power surges in the network. 6 Operation of the device 6.1 Principle of operation Functional diagram of the device is shown in Figure 6.1 . 29