Modelling A Time Controlled PRV

Hello Haniff, 

If pattern of valve settings is not giving you desired results, then you can model it with the help of controls as mentioned by Mostafa. 

E.g. if you want to control PRV settings based on flow in adjacent pipe, then you can use controls based on pipe flow. 

Creating Controls - Conditions, Actions, and Control Sets (CONNECT Edition and V8i SELECTseries 6) 

If this does not help you then please upload model files for our review. 

Sharing model files 

Hello Mostafa,

The following link has information related to using controls with valves: How can I make a PRV/PSV active after closing it with controls? To close a valve you can use the Status option. However, to reopen it, you would use the Setting option, and enter the valve setting value. An example of this is included in the link provided.

Regards,

Scott

Hi Scott,

I want to control my PRV in such a way that, it should be active only during 2am to 5am, where my network has a high pressure.

What is the difference between following two control conditions, and which one I should use?  Because they give two different results.

1. IF Time From Start >= 2.000 hours And Time From Start <= 5.000 hours
THEN PRV-6 Pressure Valve Pressure = 50 kPa
ELSE PRV-6 Pressure Valve Status = Inactive

2.IF Time From Start >= 5.000 hours And Time From Start < 1.000 hours
THEN PRV-6 Pressure Valve Status = Inactive
ELSE PRV-6 Pressure Valve Pressure = 50 kPa

Thank you,

Kind regards,

Harsha

Harsha, 

Based on your question it looks like you would do better using a clock time control rather than a time from start control. This wiki article explains the difference between the two.  The differences are that the clock time control will trigger at the specific time that is defined whereas a time from start control will trigger based on the amount of time that has passed from the beginning of the model simulation. Controls using the time from start method do not repeat past 24 hours and must be explicted stated each time they need to do trigger. 

I would suggest you try a control like this:

IF Clock Time >= 2:00 AM And Clock Time <= 5:00 AM 
THEN PRV-6  Pressure Valve Pressure = 50 kPa
ELSE PRV-6 Pressure Valve Status = Inactive

This control will make your PRV have a pressure setting of 50 kPa during the hours of 2 am - 5 am inclusive and should give it a valve status of inactive or wide open during the rest of the simulation. 

Mark

Harsha, 

Based on your question it looks like you would do better using a clock time control rather than a time from start control. This wiki article explains the difference between the two.  The differences are that the clock time control will trigger at the specific time that is defined whereas a time from start control will trigger based on the amount of time that has passed from the beginning of the model simulation. Controls using the time from start method do not repeat past 24 hours and must be explicted stated each time they need to do trigger. 

I would suggest you try a control like this:

IF Clock Time >= 2:00 AM And Clock Time <= 5:00 AM 
THEN PRV-6  Pressure Valve Pressure = 50 kPa
ELSE PRV-6 Pressure Valve Status = Inactive

This control will make your PRV have a pressure setting of 50 kPa during the hours of 2 am - 5 am inclusive and should give it a valve status of inactive or wide open during the rest of the simulation. 

Mark