Criteria to choose appropriate PLC for process

PLC
1

I want to integrate 22 XV on/off valves, 9 motors (on/off), 3 LT, 3 pH, and 7 flow meters so what should be the technical specs of PLC for integrating all the hardware and making the process automated.

Give insights in terms of I/O card and communication protocol. If possible please specify which I/o is used for which instrument as mentioned above. Hoping for a fruitful response. Thanking in advance and May God Bless everyone.

Criteria to choose appropriate PLC for process
Criteria to choose appropriate PLC for process1303×809 138 KB

2

For integrating your setup with 22 on/off valves, 9 motors, 3 level transmitters (LT), 3 pH meters, and 7 flow meters, here’s a summary of the technical specs you’d need for a PLC system:

1. I/O Requirements:

  • Digital I/O (DI/DO):
    • Valves (22 on/off) - 22 Digital Outputs (DO)
    • Motors (9 on/off) - 9 Digital Outputs (DO)
    • Total Digital Outputs: 31 DO
  • Analog Inputs (AI):
    • Level Transmitters (3 LT) - 3 Analog Inputs (AI)
    • pH Meters (3) - 3 Analog Inputs (AI)
    • Flow Meters (7) - 7 Analog Inputs (AI)
    • Total Analog Inputs: 13 AI

Note:

  1. You also need a DI card to receive the feedback signals.
  2. You have to consider motor start, stop, trip, permissive, valve feedback, etc. signals and their related I/O in the PLC.
  3. This is just a basic outline based on your input. You have to consider complete project requirements and control philosophy to finalize the required I/O.

2. I/O Cards:

  • Digital Output Card: 32-channel DO card (for the valves and motors).
  • Analog Input Card: 16-channel AI card (to cover the level, pH, and flow meters).

3. Communication Protocol:

  • Modbus RTU/TCP or PROFIBUS/PROFINET: Common for industrial instruments to integrate with other devices. (optional, check your project requirements)

4. PLC Recommendations:

  • Choose a mid-to-large PLC like Siemens S7-1200/1500, Allen-Bradley CompactLogix, or Schneider M340/M580, based on I/O capacity and protocol needs.

This PLC setup will handle all device connections and provide reliable automation.