Honeywell PKS R410 sequential control issues
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This post was last edited by “Climbing Everest on a Snail” on January 14, 2018, at 10:11. The S20 sequence has been executed; the command to open the XV20104 valve has been sent, and a pulse signal has also been sent to that valve block. However, the relay behind the panel simply doesn’t respond. The remote switching function for this valve works fine, and all feedback signals are received properly (which indicates that there’s nothing wrong with the channel relays). This valve is involved in other sequences as well; in those sequences, it functions without any issues. After resetting and restarting the sequence control system, the S20/T20 steps were successfully executed on the first try. But after completing the entire sequence, there’s a 3000-second wait period; during this time, the S20/T20 steps can no longer be executed. It’s a very strange problem…
I can’t see your step logic; it seems that the logic is incorrect (I suspect that the steps that should be executed after Restart are not being carried out). If the problem isn’t resolved, you need to share the expressions for those steps. Additionally, the PV value of your device control module is off, and the corresponding State is 4; therefore, the program conditions are not met.