Answer / koolfire

Scan time is  usually the process cycle time taken by the plc for reading the status of inputs , evaluating the control logic and then updating the outputs.
This is a continous sequential process as the PLC is constantly assesing the input and changing the output based on the contorl logic.

Scan time of plc is about 0.1 ms to 10 ms.

Answer / gowrisankar

scan time of plc means the time taken by plc to take the process parameters values.PLC scan time is very fast but field instruments are very low speed so plc made to obsolete.

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