the mains and when the alternating current is not present in the mains the relay will remains deactivated. The circuit shown in figure 2 will deactivate the relay switch when it will detect AC in the mains and in the opposite condition when the alternating current is not present in the mains the relay will remain activated. Both the circuits are isolated from the AC but it is essential to not come in contact directly with the AC part of both circuits.
Each circuit contains two parts the first part is connected with the AC mains and isolated with the PC817 optocoupler and the second part is connected with the DC supply which can be 5V to 12V. The relay switch should be used according to the DC operating voltage. At the output of the relays you can connect any AC or DC load which is under the ampere driving value written on the relay.
These simple Isolated AC detector relay switch circuits can be used in variety of projects in which ac detection is required. There are two different circuits shown in the schematics marked figure 1 and figure 2. The circuit shown in figure 1 will activate the relay switch when it will detect AC in
Hello Readers, We frequently add new circuit diagrams, so do not forget to come back often. Thank you.