This product is a simple photo sensing for pellet burners. Of course should be used to other application which need to see if fire is present. The motivation was a DIY pellet burner which made a collage of mine in the day job I have. The product made by simple the parts of my drawer so it is not any fancy or digital system. It is all analog.

First for the power supply a fuse and a varistor are the mains element against any bad happened. The device is made to used by AC or DC voltages. If you are not use the transformer then a simple DC supply of 24 volt could be used (if you need other voltages such as 12 volt or 5 volt some modification should be made in relay section mostly).

With the trimmers should be put the level you like to change the relay state.

Of course you could use any other transistor such as bc547 bc332 etc.

NEVER put DC AND AC.

The sensor which is used is that