Irrigation – Master Valves and Flow Sensors

Talk about making a complicated system even more complicated. Just out of curiosity why does your city not want 2 wire systems? 

1. Yes but that depends on where your booster pumps is located in relationship to the sub POC’s. You also might look into hydrometers in lieu of flow sensor master valves. They are more expensive but are an all in one item and saves cost in labor and layout. 

2. You would have to have another controller in order to shut off the system. 

3. That is the route you will need to go depending on your answer to question 1. 

The issue you are going to have with the parameters that you have been given is that it has been made a greater possibility that there will be cross programming on the controllers and multiple systems will try to run at the system time or on the other hand a break could occur before your fs/mv causing greater issues. 

For each controller and mv you will have to set a high flow limit. That number will depend on your critical loss calcs and should be set not to exceed that amount. The controllers will also need to be able to communicate to a central and be programmed so that maintenance contractors do not have the ability to adjust the controllers. Communication to a central is needed to controllers are programmed to work together not against each other. 

Truth be told the simplest and cheaper method would to go to a 2-wire system. 

Yes you would think that but a main line break at 1 in the morning may not get noticed until 7. 6 hours of a mainline break running is a lot of water at 4 inches. Plus 4″ mains are notorious for popping of using PVC connection. Steel fittings are highly recommended as are saddles at your valves. 

Whether or not you have tried it the city’s preferred system will required meter’s fs/mv, power, and controllers is going to cost at least $40,000 more than a two-wire system and that is not including the labor for the wiring. 

In thinking about it further you might need multiple booster pumps regardless depending your available PSI since the pump will need to be tied into the controller or tie a central controller to the bp to turn on during your water window. 

What your describing could be done for $13,000-14,000 with 2-wire. 

Good luck!

As long as the pump can kick the system on and off w/o the controller you are ok. The downside of not having it tied to a controller is that if does not turn on there will be no alarm to communicate there is an issue.