This function is implemented using the C and NC contacts of the relay. In the figure we have the way to connect the sensors or switches and below the truth table.
A B O
0 0 1
0 1 1
1 0 1
1 1 0

This function is implemented using the C and NC contacts of the relay. In the figure we have the way to connect the sensors or switches and below the truth table.
A B O
0 0 1
0 1 1
1 0 1
1 1 0