Integrated circuits containing opto-triggers like the MC3010 and MC3020 are quite popular in this type of application. Thus, as shown in the figure, we have an optodiac triggering a common TRIAC in a power circuit connected to the 110 V network. For the 110 V network the optodiac used is the MOC3010 and for the 220 V network it must be used the MOC3020. This configuration is recommended for resistive loads whose power depends only on the TRIAC used.
