PLC issues, seeking expert help
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The factory has an automatic sampling and analysis PLC system that was set to take samples every 3 minutes. Now it doesn’t take samples automatically; however, the manual motor can still be used for sampling. The timer has been replaced as well as the PLC module. I’d like to ask the experts: where could the problem lie? Under normal circumstances, the timer should light up only when sampling takes place. Now, with the new components in place, both lights are on – as shown in the picture; both the UP light and the PW light are illuminated, when they shouldn’t be on
This post was last edited by 49205455 on 2019-5-16 at 18:32, with the note that the PLC did not detect the motor contactor being engaged. Test the circuit related to the auxiliary contacts of the contactor. For example, whether the auxiliary contacts are functioning properly and whether the connected wires are in good condition. It seems this is used to control the forward and reverse rotation of the motor. Logically, it must detect the status of the motor before proceeding to the next step; otherwise, the engagement of the two contactors will cause a short circuit.
Automatic conditional activation hasn’t arrived yet, right? Just check the program online
Clean the cabinet; there’s dust or something inside, and that can easily cause malfunctions. Check the program online and monitor it to see which conditions aren’t met, so that it doesn’t proceed to the next stage – this makes it easier to identify the problem. If you don’t have the necessary resources for this, you can ask the manufacturer for guidance