How is it achieved for the mixing motor to convert current into an analog signal via a transformer and then supply it to the instrument control valve?
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With a stirred reactor, as the reaction process takes about 6 hours and the temperature is high at 250°, using a frame-type stirrer； Is it possible to achieve proportional feeding of materials by controlling the current to the stirring motor? Friends with similar experience, please give some advice. 18774777408 Engineer Li
This post was last edited by Baghdad on 2011-6-8 00:23. This approach can be considered, but it’s difficult to implement; I’ve not seen such control implemented yet. The drive motor current transformers and instruments reflect the performance of the equipment, including mechanical faults. If it is to be used for controlling the material ratio, I personally suggest looking for other approaches.
In practice, we adjust the feeding and discharging of materials by monitoring the stirring current; it is said to work well. I checked the Yidian chain atlas, but I’m not sure about the results
Obviously, you need a current signal detection transmitter that is capable of outputting a 2–20mA signal. Additionally, you need a controller that can receive the signal from the transmitter and set the desired value, thereby outputting another signal to control the valve. Look, if the hardware is available for purchase, then implementation isn’t difficult. It should be fine, I guess
This post was last edited by Arno Baliang on 2011-6-14 at 17:01; it should be possible to do it. The current of the mixing motor can be used as the PV value (that is, the actual current value of the mixing motor), while the normal current value of the motor serves as the SV value (that is, the set value). This can be achieved through a simple single-loop control system; furthermore, by adjusting the PID parameters and utilizing the forward and reverse actions of the regulator, a 4-20 mA signal can be generated to control the control valve. A ratio adjustment scheme can be used with 2 types of materials. Of course, before feeding it to the regulator, you need to convert the stirring current using an current converter into a standard signal that the regulator can accept, such as 4-20mA DC or 1-5V DC.
I get it, I understand; I’ve learned more knowledge again. Thank you!
Thank you all for your support. This post was posted by a friend, Engineer Li, and the issue has been resolved. Everyone is right; it is possible to control the amount of material fed in using the motor current (with a constant ratio between the two types of material). When more material is fed in, the power consumed by the mixing motor increases, and thus the current level rises; when less material is fed in, the current level is lower.