Operational Controls (PMP) not working as expected


I am trying to run the following scenario "P2 2 hr FF @WTP EPS" and "P2.4 2 hr FF @WTP EPS" in which

1. There is a 2 hr fire flow which occurs near the water treatment plant (WTP, J-600, simulated with negative demands) at J-607, downstream of PMP 600 starting at time 17:00 and running until time 19:00. The demand at J-607 at all other times is 15 gpm. From 17:00 to 19:00 a demand pattern increases the demand at J-607 to 1,500 gpm to simulate the fire flow.

2. PMP 600 pumps water directly to the tanks on top of the hill (south end o model). T-200 and T-1. Water then flows from these distribution tanks into the system at three locations (J-602, J-604 and J-12).

3. Mast meter locations (simulated with a reservoir/ FCV valve setup) also allow water into the system at various locations to help meet demands.

4. There is also a pump (PMP 1) at the top of the hill that feeds water into T-1 and T-200. 

5. The WTP (J-600) fills the tank at the WTP (T-600). Water from T-600 is pumped by PMP 600 to T-1 and T-200 by PMP-600 on top of the hill via a dedicated transmission line. During a fire water at the WTP, water can flow back through the transmission line to the WTP. This line also accepts water from the system through a bypass at two of the locations discussed above (J-602J-604 and J-12).

6. PMP-600 at the WTP is controlled by the level in the tank (T-600) at the WTP. It is set to turn off if the level in T-600 gets too low and turn on if the level in T-600 gets too high. 

7. PMP-600 is also controlled by the levels in the tanks it is filling (T-200 and T-1) but the controls discussed above have a higher priority. In other words, if the tank at the WTP doesn't have enough water in in (level too low), then PMP-600 will turn off regardless of what is happening with the water levels in T-1 and T-200.

8. There is also a control on PMP-1 at the top of the hill that tells this pump to turn on when the tank levels in T-1 and T-200 are too low, or off when the tank level in T-1 or T-200 are too high.

I would like to simulate the worst-case scenario in which the pumps lose power during the peak hours (17:00 to 19:00) while there is also a fire at the WTP despite the likelihood of the situation

I want to run the fireflow simulation as an EPS to see how the system reacts to the fire, if the tanks on top of the hill (T-1 and T-200) will drain, causing undesirable pressures in Pressure Zone One, just north of these tanks or if the master meter locations can provide enough water/pressure to make up for the water leaving the tank to fight the fire at the WTP etc. There is also a bypass at two of the three locations mentioned above (J-602, J-604 and J-12) which allows water to flow from the system into the pipeline which supplies water to the WTP. 

The problem is that the controls don't seem to be operating the way I think they should. The pump at the WTP (PMP-600) is not turning off at the specified time and is turning on way more frequently throughout the day when I use the clock time control. When I go into the operational controls alternative and turn the clock time control for PMP-600 off, the system acts as I would expect it to. I am not sure if I am doing something wrong or what.

I will upload the file through the secure file upload.



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