Cycle Stop Valves. 1 ” through 16 ” 1 GPM to 10,000 GPM. Using a Cycle Stop Valve, the flow rate from this pump will exactly match 1 or 100 sprinklers so, an 86 gallon tank can replace 10,000 gallon tank. Questions about Pump Control Valves. Resting Pumps and Motors?
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
1” through 16”1 GPM to 10,000 GPM
Using a Cycle Stop Valve, the flow rate from this pump will exactly match 1 or 100 sprinklers so, an 86 gallon tank can replace 10,000 gallon tank
Pumps are made for continuous duty, they never need to rest.
CSV has a mechanical soft start and stop but, soft starter can be used to reduce end rush.
Back Pressure does not hurt pumps. Pumps only think they are in a deeper well.
Pumps need very little flow to remain cool. Derated motors also need very little cooling.
Recirculation not cavitation happens at low flow. Good impellers with high tensile strength will resist wear from recirculation.
Example; Back Pressure & Differential PressurePump Dead Head in PSI = 250 PSIStatic Water Level 150’ = 65 PSI250 – 65 = 185 PSI Max inlet pressure or back pressureAll pipe and fittings before the CSV will see 185 PSI If you have 185 PSI coming into the CSV and the CSV is set at 60 PSI then 185 – 60 = 125 PSI differential pressure through the CSV.Differential Pressure must always be less than 125 PSI
If differential pressure is more than 125 PSI, use two or more valves to stair step the pressure down to the required pressure.Example; Differential Pressure is 200 PSI, max inlet pressure is 250 PSI and system requires only 50 PSI.First valve sees 250 PSI and is set for 150 PSI.Second valve sees 150 PSI and is set for 50 PSI.This gives 100 PSI differential through each valve.
Choking back on pumps with centrifugal impellers Reduces Horse Power, RPM doesn’t need to change.(note constant 3450 RPM and Power required still changes from 10 HP at 200 gpm to 4 HP at 50 gpm)
Valve Outlet Pressure
Required Flow in GPM ________Required Pressure at use ________Depth to pumping level ________Elevation from pump to use ________Friction loss in pipe and valves_______ Pump Dead Head ________ Static Water level _______
Example;Required Flow in GPM 180Required Pressure at use 50Depth to pumping level 0Elevation from pump to use 0Friction loss in pipe and valves 10Total pressure from pump 60 Pump Dead Head 80 Static Water level 0
Pump Dead Head Pressure 80 PSIPressure Switch Shut Off 60 PSICycle Stop Valve 50 PSIPressure Switch On 45 PSI
Make sure pump dead head pressure is at least 10 PSI higher thanpressure switch shut off pressure
Friction Loss for CSV3B is 14 PSI.When there is less than 100 PSI differential pressure, the cover spring can be removed which decreases friction loss to 7 PSI.7 PSI friction loss means the pump must deliver 57 PSI to get 50 PSI at max flow rate.Friction loss with Cycle Stop Valves only applies at maximum flow rate.
Reduced Pressure Fall Off has nothing to do with Friction LossJust means the CSV must be set at 61 PSI while using 1 GPM, to get 50 PSI for a 20 GPM sprinkler zone
Only when required system flow is less than minimum for CSV will pump be allowed to cycle.Example; CSV3 has 5 GPM minimum and the system has a 2 GPM leak.Tank size is very important.
When required system flow is greater than minimum flow for CSV, the pump will run continuously.I.E. CSV1 has 1 GPM minimum CSV3 has 5 GPM minimumSystem never gets below 7 GPM usage.Tank size is not important as pump will run continuously.
Multiple Pumps work together by simply staggering pressure settings.Pump #1) 5 HP SubOn at 70 off at 80 PSIPump #2) 50 HP TurbineOn at 60 off at 70 PSIPump #3) 75 HP TurbineOn at 50 off at 60 PSI
Pressure Switch placement is very important.Switch must be as close to the tank as possible.No elbows or tees between the switch and the pressure tank.
Water line going to the tank should never be larger than the tank inlet connection.I.E. 1.25” elbow under tank means no larger than 1.25” pipe from main line to tank.
In well pressure tank only holds 3/4 of a gallon.These tanks work great like any other small tank as long as there are no leaks in the water system.
If there are leaks in the system, add an additional or larger tank.This keeps the pump from having to start every time ¾ of a gallon has leaked out.See Tank Calculator on our web page.