reducing scan times

[mr_electrician]

Hello, can someone tell me how I go about reducing my scan time. I tried to program my conveyor system as simple as possible but the program seems to stall one and awhile. As I type this I am thinking that a stalled program would error out my PLC so I am not sure whats up.

[Rod_Hackney]

If you can post your code in a PDF file, I am sure this site can give assistance. I do not have the S7-200 software but have used it in the past. IF your not getting a scan error and shutting down the plc it may be a logic glitch in the program that is only happening under certain circumstances.

[dekor]

Hi, mr_electrician I want suggest you some simple things that can help you. Go in: system blocks \ input filters\ and change the default values (6.4ms) to minimum (0.20ms). Normally this would be enough. If is still not, try to use "catch pulse bits" option and select the inputs that you consider are necessary. If is still not, try to decrease the "background time" to 5%. " You can configure the percentage of the scan cycle time that will be dedicated to processing the communication requests associated with a RUN mode edit compilation or execution status. As you increase the percentage of time that is dedicated to processing communication requests, you are increasing scan time, which makes your control process run more slowly. The default percentage of the scan time dedicated to processing communication requests is set to 10%. This setting was chosen to provide a reasonable compromise for processing compilation/ status operations while minimizing the impact to your control process. You can adjust this value by 5% increments up to a maximum of 50%. " (SIEMENS HELP TEXT) dekor

[mr_electrician]

Thank you very much for your help. I will try your suggestions and let you know of the results.

[ramaslabas]

Do not forget inform about results. I have downloaded your program. Surprised, that you have problems with scan time