Comparative experiment: the influence of different driving modes of stepper motor on the accuracy of peristaltic pump

First of all, we must first understand what these three driving methods are?

④Place the liquid outlet in a graduated cylinder with a suitable range, and be careful not to stick to the wall to prevent the liquid from hanging on the wall and affect the experimental results; and record the running time;

⑥ After the pump is finished, observe and record the actual volume of the pumped fluid;
⑦ Repeat the above operation to test and record the operation data of all peristaltic pumps
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3.
Precautions
① Before the experiment of the peristaltic pump, uniformly use a No.
16 silicone tube to pump out a volume of 20 mL of the pumped liquid at a speed of 50 rpm for calibration
.

② During the experiment, no matter how much difference there is in the volume of the pumped liquid, the calibration operation cannot be performed again
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③ When reading the volume of the pumped liquid, place the measuring cylinder on a flat table so that the line of sight and the lowest part of the liquid concave liquid in the measuring cylinder are level
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4.
Analysis of
experimental data After sorting out the experimental data, the following table is obtained:

(Stepping Motor Drive Accuracy Test)


(Diagram of Scattered Points for Accuracy Test)

As can be seen from the data in the table, once the speed and pump output are changed, the peristaltic pumps controlled by different driving methods will have different results
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Among the three drive modes, the RS-485 communication mode has the best control accuracy, followed by the pulse, and the analog quantity has the largest error
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Advantages of RS-485 Communication

The RS-485 communication mode not only endows the peristaltic pump with high control precision, but also has the following advantages:
① Stable system operation—use the dedicated communication bus to connect the concentrator and the master station safely and reliably
.
Unless the device interface hardware is damaged, or the bus line is disconnected, the bus meter reading system will always maintain a good communication effect and success rate of reading
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② High communication rate - due to the use of a dedicated wired communication line connection, there is no other signal on the line except for communication signals
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And the attenuation after the external interference signal is coupled to the line is very large, so the concentrator can communicate with the master station at a higher rate
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③ Anti-interference - RS-485 bus channel is a dedicated communication channel.
The shielding added to the communication cable can effectively ensure the communication effect, so it has strong anti-spatial interference performance
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The HOLVES bioreactor has basically been updated to the RS-485 communication mode in the driving mode of the stepping motor, which effectively improves the control performance of the peristaltic pump during the fermentation process
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HOLVES has been striving to improve the performance of bioreactors in an all-round way, hoping to provide more automated and sophisticated equipment for biological experiments
.

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Note: The content of this article is copyrighted by HOLVES.
Unauthorized reproduction and use are prohibited
.