New equipment and instrumentation joint school, I would like to ask and exchange some questions with you.
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New equipment and instrumentation joint school, I would like to ask and exchange some questions with you.: 1. The liquid level of Japan's Yokogawa CS3000 system is mm and the flow rate is kg/h. For those who have used this system, should I convert the units into meters or tons/hour, or should I keep the original units of the system? 2. What should you pay attention to during instrument joint calibration, such as the role of split-range control and cascade control? Are there any problems with the control valve during the start-up process? Since this is my first time cooperating with a joint school, if there are some important points that I haven’t mentioned, I hope you can add them. Thank you! !
The control valve got stuck during the start-up process. There is no good solution. I can only check more. This post was last edited by chengkang on 2009-4-15 13:04 ]
1. Look at the individual* It’s okay if you don’t convert the liquid level. It’s best to convert the flow rate because it’s different from ours. * The usage is quite different. 2. There will usually be problems with the instrument regulating valve, and some may even move in the opposite direction. Special attention should be paid to this during joint schooling, otherwise big trouble will occur.
1. There is no need to convert units.* Just get used to it. 2. When jointly calibrating instruments, attention should be paid to whether the control valve switch is flexible, whether the valve position is in place, whether the switch is reversed, and whether the switch state of the control valve in an accident is consistent with the design. Whether the control valve operates correctly when the control variable changes.
Of course the conversion is good, the operator* If you get used to it, it is easy to make mistakes. The new instrument system must be carefully calibrated. There are many problems such as control valve reverse direction, measurement conversion errors, point mismatch, inability to cast automatic control, wrong signal connection, etc.
Check each circuit carefully! Problems will be detected after calibration! One of the purposes of new equipment in water combined transportation and cold oil transportation is to check and test the instruments! Check as many times as possible during this process!
Liquid level is generally 0-100%, but it varies with each device operator.* It depends on your habits. I have used CS3000 to jointly debug 4 sets of devices with instruments in my unit. The main problem was the cooperation with the instrument workers.
If you are working on DCS, you should know some process, instrumentation, and electrical knowledge, which will help you get twice the result with half the effort in joint debugging.
1 The liquid level unit can be selected according to the situation. M mm % 2 If the pipeline is not purged clean, many valves will get stuck. Pay attention to the positive and negative effects of the valve.
The joint calibration of new equipment instruments must be more detailed. It is best to formulate a table to list all the instruments on the DCS. On the one hand, control instruments such as regulating valves must test whether the switches are flexible and in place and whether the mode of action is correct. Instruments such as flow, pressure, temperature, liquid level, etc. also need the cooperation of the construction unit on site. Dismantle the instrument wires one by one to see if they are consistent with the indoor DCS display to prevent incorrect connections. This situation is very possible, especially for similar display meters of the same type, which are not easy to find. If there are errors that are not found, etc., and other abnormal operations occur, you may not be able to figure out why this is the case. Then there is the problem of display units. If the content of your DCS screen is relatively tight and the units are small and long and difficult to arrange, then convert the units and keep two digits after the decimal point. If your DCS screen has many empty spaces, it is best to use smaller units. After all, the smaller the unit, the more sensitive the display. The above are some personal opinions.
I won’t go into the unit conversion, it depends on* Depends on custom, we need to convert it into tons/hour here. ； I think there may be problems with the instrument valve. The main reasons are that the valve position is stuck or not in place, the positive and negative effects are wrong, and the control valve is installed in the wrong direction.
Ensure that the forward and reverse functions of the regulator are correct, the actuator is flexible and in place, each monitoring instrument is installed correctly and easy to use, be familiar with DCS, and try to eliminate all problems before starting work.
During the joint schooling process, please note that some instruments may have inappropriate ranges.