Hi,
Help me building this logic in AB’s ladder logic format. I have ControlLogix PLC.
In field, I have three pumps connected in series. Say Pump-A, Pump-B, and Pump-C.
Every time “START” bit goes TRUE, two of the pumps should start but not the third one.
In below combination:
START = Start (Pump-A and Pump-B)
START = Start (Pump-B and Pump-C)
START = Start (Pump-C and Pump-A)
And then again… same cycle repeats.
Please note that I have only one “START” bit … I mean, had there been three different “START” signals I could have placed them to start in above combination. Every such START command will stay TRUE for 4 hours and then will remain FALSE for one hour. Then again START command for 4 hours…and so on. BUT EVERYTIME THIS START COMMAND COMES; PUMPS SHOULD START IN ABOVE COMBINATION ONLY.
This logic is because I do not want same pair of pumps to run all the time and get heated.
Please help in developing this ladder logic.
Thanks in advance,
Saurabh
Help me building this logic in AB’s ladder logic format. I have ControlLogix PLC.
In field, I have three pumps connected in series. Say Pump-A, Pump-B, and Pump-C.
Every time “START” bit goes TRUE, two of the pumps should start but not the third one.
In below combination:
START = Start (Pump-A and Pump-B)
START = Start (Pump-B and Pump-C)
START = Start (Pump-C and Pump-A)
And then again… same cycle repeats.
Please note that I have only one “START” bit … I mean, had there been three different “START” signals I could have placed them to start in above combination. Every such START command will stay TRUE for 4 hours and then will remain FALSE for one hour. Then again START command for 4 hours…and so on. BUT EVERYTIME THIS START COMMAND COMES; PUMPS SHOULD START IN ABOVE COMBINATION ONLY.
This logic is because I do not want same pair of pumps to run all the time and get heated.
Please help in developing this ladder logic.
Thanks in advance,
Saurabh
