Moscow, Azovskaya 14
+7 (495) 310-97-15
Mo-Fr: 9.00 - 18.00 (Moscow time)
Order a call
Your name *
Enter phone *
Your Email *
Call me back

Description of locks and protections

Причинно-следственная диаграмма

Blocking table (Cause&Effects Diagrams) indicating control actions.

When describing control algorithms for APCS systems, for the qualitative implementation of all (sometimes contradictory) functions, it is required to separate control algorithms from protection functions. Blocking and protection algorithms have the highest priority over the actions of the system operator and automatic control algorithms, and access to change these functions is protected by a password. The picture above shows a description of the blocking and protection scheme in the form of a cause-and-effect diagram (PSD).

Blocking – This is a prohibition of any action on the device. For example, it is possible to open a valve, but it is no longer possible to close it until the cause of the blockage is eliminated.

The concept of blocking in the APCS is a measure to prevent actions on the control object. Protection action or PSD blocking.

Protection – it is a direct action on an object. For example, if the liquid level in the tank is exceeded, the pump must be turned off.

This tabular (cross) method of providing information is the most beneficial in terms of implementing protection and blocking algorithms (it is built by analogy with the Safety Matrix program).

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

1. the name of the positions of the sensors is placed, the readings of which should lead to any actions provided for in the event the process goes beyond an abnormal situation

2. describes the type of reservation selected. 1 out of 1, this means that there is only one sensor at this control point

3. information is placed describing the purpose of the sensor in the flow diagram

4. type of medium on which the sensor is located

5. threshold value of the parameter, which is the criterion for the occurrence of blocking

6. time delay, which must be maintained before the implementation of the blocking. This delay is implemented to filter triggers in case of a blocking condition for a short period of time.

7. The crosshair displays the place that is the cross for the triggering condition of the locks. If a blocking condition occurs in this line, then the command is transferred to the dependent column, thus this method allows you to linearly design protections.

8. the position of the actuator that has blocking conditions

Причинно-следственная диаграмма

#locksandprotections, #Blockingtable, #automationdesign, #PSD

Be the first to comment

You comment add