OR Gate
The OR gate is used to indicate that the output occurs if and only if at least one of the input events occur. Logically, there must be at least two inputs to an OR gate. However, the FTA module does not force this to be the case.
Summary of Logic:
If at least one event is TRUE, the output is TRUE. If all events are FALSE, the output is FALSE.
A truth table for the OR gate follows. The Boolean equation for an OR gate is T = A + B.
A | B | Output |
|---|---|---|
T | T | T |
T | F | T |
F | T | T |
F | F | F |
Example
A vehicle will not start if it has no fuel OR if it has some other mechanical problem.
