Read PID chart
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This post was last edited by zylyx520 on 2012-8-23 07:42. Please tell me how to read PID diagrams; I’m a beginner and I can only read PFD diagrams
Understand all the legends first, then examine the equipment and pipes step by step, treating each circuit as a whole – patience and careful attention are all that’s needed
All pipelines need to be connected to the equipment, so it is possible to start from the equipment and follow the pipelines downward. Of course, it is first necessary to understand the legend and the codes for the media used!
I mainly can’t understand the instruments; could you give some good advice? I study equipment.
In simple terms, instruments can be divided into four main categories based on their function: temperature, pressure, flow rate, and level. The initial letters corresponding to these categories are T, P, F, and L respectively. By learning the meanings of these instrument symbols, you will know what purpose each instrument on a PID controller serves!
My summary is to first memorize those symbols, especially those related to control valves – determining whether they are used to control flow rate or temperature and pressure. After that, analyze the interconnections between these elements. Of course, controlling the bypass systems is also important. Additionally, it’s necessary to figure out whether control is done through proportional control or feedback control. Take your time and study patiently; it will be easy once you do that.
You can check it out at http://www.docin.com/p-477299186.html
If you look at it more often, you’ll understand; it doesn’t seem that difficult. First, identify the main process, then the subordinate processes, and finally consider the control aspects related to the instruments.
When searching for PID information, I see many graphs related to tuning parameters such as P, PI, and PD. How should one interpret these graphs, and what does it mean when the system is considered to be tuned stably?
First, take a look to understand and remember the legend, then start by looking at the devices.
The general pipeline layout can be referred to in the PFD; pipeline numbers can be found in the pipeline table, instruments are indicated by the legend, and the actual piping layout can also be seen from on-site photos. The most challenging parts seem to be the naming and symbols of the instruments. For example, it’s difficult to understand the instrument transmitters and controls, logical signals, and interlocks related to reactors, fuel gas, and air. In such cases, it’s better to ask the experienced technicians for guidance; for the rest, it’s possible to figure things out by spending more time on it oneself