How does DCS achieve the control of shared equipment?
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I would like to ask an expert: A pump feeds liquid into three flow meters. How can a DSC enable the flow meters to control the pump? Thank you!
The question is too general; others cannot help you accurately. Please provide more details or draw a flowchart so that everyone can give a targeted response. If it is controlled by an inverter, control the frequency of the inverter; if it has a bypass valve or other valves, consider the valve as the control object.
General control approach: The pump is not involved in the control; the three circuits are each controlled via a flow meter and a control valve； If pump control is required: add ; to the existing control setup; install an inverter for the pump and a pressure sensor at the pump’s outlet ； Through pressure frequency modulation, (individual control circuit)
The estimation of the same variable can’t be controlled via three channels, right? It can be set based on three variables, such as liquid level, temperature, flow rate, pressure, etc
Thank you for the help! My question is: My company has a raw material stored in a tank, which is pumped to three different locations for use; each location is equipped with its own mass flow meter. I want to be able to start and stop the pumps automatically based on the flow rates, so that the material isn’t used simultaneously. Could someone with expertise please advise me on how to achieve control of the pumps using a DCS system? Thank you!
This should be achievable: add a ≤ condition for the flow rate of each pump, and use OR logic to output a start signal (DO) to the electrical control circuit. Auxiliary signals required: Pump operation indicator (DI). Others: Do the three flow meters have priority? That is, when the pump’s capacity is insufficient, which flow meter should be given priority? If priority is required, an automatic control valve is also needed to regulate the flow rate. What needs coordination: The electrical department is responsible for modifying the electrical control circuits
I don’t know how to respond regarding the rating~~~~ The signal for starting and stopping the pump is indeed provided by the instrumentation department, but that signal is just a DO signal; the actual control for starting and stopping is carried out in the electrical secondary circuit. Our company maintains a clear separation of responsibilities in this regard.
Thank you all for your guidance; I will pass this on to the Instrumentation and Electrical team.