Description of Interlocks and Protections


Table locks (use Effects Diagrams) indicating management actions.

In describing the system control algorithms APCS for quality implementation of (sometimes conflicting) functions required separate control algorithms of the protection functions. Algorithms locks and protection have top priority over the actions of the system operator and the algorithms of automatic control and access to change these functions are password protected.

Lock is a prohibition of any act on the device. For example, the valve can be opened and closed is no longer possible to eliminate the causes of the lock.

The concept of locking in automatic process control system – a measure to prevent the action with the object management.

Defense is a direct effect on the object. For example, in case of exceeding the liquid level in the reservoir the pump must be switched off.

This table (cross) the method of providing information is

the most profitable in terms of implementation and protection algorithms

locks (built by analogy with the Safety Matrix program).

The following is a transcript of the rows and columns of positions:

1. Placed the name of the position sensors, the indications which must
lead to any action provided for in the event of
process for contingency

2. Describes the type of the selected backup. 1 of 1, it indicates that the sensor
in that only one test point

3. Provides information describing the sensor appointment

4. The type of media on which the sensor

5. The threshold value, which is the criterion of origin

6. The time delay that must withstand up to realization
lock. This delay is implemented to filter alarms
in case of interlocking conditions for a short

7. Crosshair displays the location, which is the cross for the condition
trigger lock. In case of a given line
Interlock conditions, the command is transmitted to the dependent column, the
This method thus allows to design protection linearly.

8. The position of the actuator, which has a blocking

    Russian version