ITEM TOOLKIT

6. Right Mouse Click on the new Gate and select Gate Parameter.
7. Enter “No current to point B” as Description (E).
8. Click OK when finished (F).
Chapter 8 Fault Tree 185
Types of Gate
The following gates are supported in the Fault Tree module:
• OR Gate
The OR gate indicates that the output occurs if any one of the input events occurs.
• AND Gate
The AND gate indicates that the output occurs if all of the input events occur simultaneously.
• PRIORITY AND Gate
The PRIORITY AND gate indicates that the output occurs if and only if all of the input events occur in the order from
left to right.
• VOTE Gate
The VOTE gate indicates how many of the gate inputs need to occur to cause the gate failure to occur. For example, if
the gate has four inputs and a vote of three was specified, this indicates that at least three of the gate's four inputs would
have to occur to cause the gate failure to occur.
• XOR Gate
The XOR gate indicates that an event will occur if one but not both of the input events occur.
• NOT Gate
The NOT gate indicates that the output event occurs if the input event does not occur.
• NULL Gate
The NULL gate indicates a single input only. These gates are used to allow additional descriptions to be added to the
fault tree for system events.
• TRANSFER/Subsystem Gate
The TRANSFER/Subsystem gate indicates that this part of the fault tree is developed in a different part of the
diagram or on a different page.
• INHIBIT Gate
The INHIBIT gate indicates that the output event occurs if both input events occur. One of the inputs represents a
conditional event.