Saturday, June 09, 2007
my perfect control system 1
Normally, the design of a control system is based on engineering drawings and specifications of the mechical/electrical system. From these, we extract Level 1 information, most of which are independent to the hardware of the control system (i.e. no size and selection of valves, damper actuators, sensors etc.). Level 1 information is considered as the core information of a control system. It reveals the nature of the system.
That brings up the first question. What's the best format to record and present Level 1 information? Often, designer uses control system hardware drawing to present it. But that's not a good way. since it contains much more than Level 1. The importance of Level 1 is dilluted in a sea of information. The best presentation of Level 1 should easily have a designer capture the nature of the system in a couple of minutes.
Level 1 (core):
1, A plant list that summarize all equipment and plants under control.
This provides all designers and managers a big picture of what the system is. And from this, the index of hardware drawings and the navigation menu of graphics are easily created.
Moreover, the plant list is useful for all kinds of engineering hour and material cost analysis at marco level.
2, A point list arranged by controllers
This is the only item that is hardware related. But we only need to know how many of each type of points each controller can handle. Since I try to keep the design system as much hardware independent as possible, the rule of controller's point capability should be configurable.
Is there a similar hardware drawing can be followed/reused?
When creating graphics, one needs to know things such as where all the exhaust fans are?
3, Control sequence
The control sequence is not just simply copy and paste from mechnical drawings or specifications. It should be the decided sequence that will programmed in the selected controllers.
What are the software subroutines should be used? Is there a similar controller program that I can follow/reuse? What exactly are the differences? How to change it to satisfy the current need. (Search and comparison)
What are the most common used subroutines? (Application library optimization)
That brings up the first question. What's the best format to record and present Level 1 information? Often, designer uses control system hardware drawing to present it. But that's not a good way. since it contains much more than Level 1. The importance of Level 1 is dilluted in a sea of information. The best presentation of Level 1 should easily have a designer capture the nature of the system in a couple of minutes.
Level 1 (core):
1, A plant list that summarize all equipment and plants under control.
This provides all designers and managers a big picture of what the system is. And from this, the index of hardware drawings and the navigation menu of graphics are easily created.
Moreover, the plant list is useful for all kinds of engineering hour and material cost analysis at marco level.
2, A point list arranged by controllers
This is the only item that is hardware related. But we only need to know how many of each type of points each controller can handle. Since I try to keep the design system as much hardware independent as possible, the rule of controller's point capability should be configurable.
Is there a similar hardware drawing can be followed/reused?
When creating graphics, one needs to know things such as where all the exhaust fans are?
3, Control sequence
The control sequence is not just simply copy and paste from mechnical drawings or specifications. It should be the decided sequence that will programmed in the selected controllers.
What are the software subroutines should be used? Is there a similar controller program that I can follow/reuse? What exactly are the differences? How to change it to satisfy the current need. (Search and comparison)
What are the most common used subroutines? (Application library optimization)
