Define an interlock

The way you define an interlock depends on the type of block you are working with. This method applies to Device Control blocks.

Right-click the DEVICE_OPTS parameter in the Parameter View of the Device Control Block, and then click Properties. The Properties dialog is displayed.
Select Interlock, and then click OK.
Right-click the STATE_MASKS parameter, and then click Properties. Select Passive and Active 1 for both input 1 and output 1.
If you have any more than two states, such as in the case of a multivariable motor, also select Active 2 for both input 1 and output 1.

When the interlock conditions become True, the outputs are driven to the Passive state. (This is usually the normal state, like stop or closed, depending on the type of device.)

Note

If you are using a Loop or PID block, you must interrupt the output by putting a transfer block between the PID output (Track PV or Out) and the analog output (AO) block. Then, create a condition for the interlock that either passes the PID output through to the analog output or does not pass it through, depending on that condition.