Specifying Irrigation Pump Stations. How to Size and Specify Booster Pumps. Tony Adamson Rain Bird Pump Sales & Marketing Manager

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1 Specifying Irrigation Pump Stations How to Size and Specify Booster Pumps Tony Adamson Rain Bird Pump Sales & Marketing Manager

2 How to Size and Specify Pumps for a Booster Application

3 Booster Application Pump that is developing 60 PSI (138.6 Feet of Head) 20 PSIG 80 PSIG Suction Discharge

4 What is the Water Source? Well Lake Pond River Ditch Public Source (metered or pressurized) Above Ground Tank

5 What needs to be determined to specify a pump? Required Flow Rate Inlet and Discharge Pressure Water Application Requirements (e.g., water window) Pump station location any restrictions such as size, existing building, view of the public, etc. Elevation impacts how the pumps are rated Inlet/Outlet piping size requirements Available power in volts/phase/hertz

6 Pumps for the Application Split Case Centrifugal Typically up to 2000GPM Typically up to 130PSI Vertical Multi-Stage Horizontal End Suction Vertical Multi-stage Up to 500GPM per pump Wide range of pressure

7 Vertical Turbine Pumps for the Application Vertical Turbine Typically up to 1000GPM per pump Wide range of pressure Motor on top Submersible Turbine Typically up to 600GPM per pump Wide range of pressure Motor on bottom Submersible Turbine Pump Motor Location Pump Motor Location

8 Variable Frequency Drive (VFD) Every main motor on a Rain Bird Pump Station is started on the Variable Frequency Drive (VFD). 1) Soft starting of every motor provides motor longevity 2) VFD saves energy by only powering the pumps that are needed based upon demand 3) Heat Exchanger keeps the VFD cooled and the electrical box free from dirt and dust

9 Key Numbers and Units You get 120PSI for every 10HP 60HP pump delivers 120PSI 75HP pump delivers 120PSI If pressure, flow 100PSI = 231FT The discharge of a pump is usually stated in Feet The discharge of a pump station is usually stated in PSI Friction Loss (Schedule 40 Steel Pipe) 1000GPM in a 10 pipe suffers 5FT head loss per 1000FT of pipe

10 Electrical Power Most common types of power in U.S. 460 V, 60Hz, 3Φ Can power pumps up 500HP 230 V, 60Hz, 3Φ Can power pumps up to 100HP 230 V, 60Hz, 1Φ The largest motor available in 1Φ 230V is 10HP Rest of the World Power: Canada: 575 V, 60Hz, 3Φ Asia & Middle East: 380V, 50Hz, 3Φ

11 Hydraulic Design - Pump Curves

12 The Pump Curve Bowl Power BEP (Best Efficiency Point) Bowl Efficiency NPSHr

13 The Pump Curve Bowl Power The power input required to generate a given flow and pressure. Bowl Efficiency The ratio of hydraulic power output from the bowl to the power input to the bowl e.g. A bowl with required a 75HP motor to generate a 50HP hydraulic output would have a Bowl Efficiency of 50/75 = 67% BEP (Best Efficiency Point) Point of highest bowl efficiency. You want your operating point to be as close to BEP as possible. NPSHr Net Positive Suction Head Required Pressure required on the intake side of the pump to ensure proper operation.

14 The Pump Curve Bowl Power The power input required to generate a given flow and pressure. Bowl Efficiency The ratio of hydraulic power output from the bowl to the power input to the bowl e.g. A bowl that requires a 75HP motor to generate a 50HP hydraulic output has a Bowl Efficiency of 50/75 = 67% BEP (Best Efficiency Point) Point of highest bowl efficiency. You want your operating point to be as close to BEP as possible. NPSHr Net Positive Suction Head Required Pressure required on the intake side of the pump to ensure proper operation.

15 The Pump Curve Bowl Power The power input required to generate a given flow and pressure. Bowl Efficiency The ratio of hydraulic power output from the bowl to the power input to the bowl e.g. A bowl with required a 75HP motor to generate a 50HP hydraulic output would have a Bowl Efficiency of 50/75 = 67% BEP (Best Efficiency Point) Point of highest bowl efficiency. You want your operating point to be as close to BEP as possible. NPSHr Net Positive Suction Head Required Pressure required on the intake side of the pump to ensure proper operation.

16 The Pump Curve Bowl Power The power input required to generate a given flow and pressure. Bowl Efficiency The ratio of hydraulic power output from the bowl to the power input to the bowl e.g. A bowl with required a 75HP motor to generate a 50HP hydraulic output would have a Bowl Efficiency of 50/75 = 67% BEP (Best Efficiency Point) Point of highest bowl efficiency. You want your operating point to be as close to BEP as possible. NPSHr Net Positive Suction Head Required Pressure required on the intake side of the pump to ensure proper operation.

17 Low Profile Pump

18 Pump Selection Based on pressure and flow

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20 Electrical Calculations

21 Estimating Station FLA **For 208V applications, increase the FLA by 10% To calculate the FLA of a pump motor operating on a VFD, multiple the nominal FLA by 1.24 To estimate FLA, multiple the largest load by 1.25 and then add this to remaining component FLAs. Example: a 460V 2 x 100HP pump station with a 25HP PM pump would have an FLA of 340 Amps. 334 Amps = 1.24x1.25x120A + 120A + 34A

22 Other Electrical Panel Components Surge Protection. Helps protect the pump station against transients associated with power disturbances. Step-down Transformer. Provides 120V single phase control power. Through-Door Main Electrical Disconnect. Shuts off power to the electrical panel if the panel door is opened. Optional 7.5KVA Step Down Transformer. Provides additional 120V power.

23 Specifying a Booster Station A contractor has a 200GPM line from the city coming in at 15PSIG. He needs to boost the pressure to 155PSIG to overcome elevation changes at the site. The contractor requests a two pump system for redundancy purposes. The altitude at the site is 1900FT. Available power is 208V, 3Φ

24 Specifying a Booster Station 155 PSIG 15 PSIG 100GPM at 140PSI 200GPM at 155PSI 100GPM at 140PSI

25 Specifying a Booster Station 155PSI 15PSI = 140PSI 140PSI is referred to as the Pump Differential Pressure. 200GPM at 155PSI 2 pumps, each capable of providing 100GPM at 140PSI. Add 5PSI to account for station losses 100GPM at 145PSI 100GPM at 335FT Note: The high pressure requirement indicates that a vertical multi-stage pump should be used. Use the published pump curves to select pump.

26 Vertical Multi-Stage : 15HP 72.5% Efficient

27 Vertical Multi-Stage : 15HP 72.5% Efficient Insert Pump Curve for the 2-15HP

28 Horizontal End Suction 35HP 53% Efficient 20% less efficient as vertical multi-stage

29 Specifying a Booster Station Result: two 15HP multi-stage pumps. Efficiency at the design point is ~72%. Now calculate the estimated station FLA: Station FLA = 1.25 x Largest FLA + Remaining FLAs (1.25 x 1.24 x 42A + 42A) = 118A (200 Amp Service)

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33 Pump Station Options Control Systems Z-Pipe Stainless Steel Intake Box Screen Power Conditioner Pump Station Heater Lake Level Control Wye Strainer Power Zone Transformer Filter (Rain Bird, Amiad, Tekleen, Orival or Other) Cable or Radio Modems Fertigation Enclosures Magnetic Flow Meter (instead of the standard paddle wheel style) AC VFD Cooling Powder Coat, Stainless or HDPE

34 Display Options E1071 Full Color Touch Screen (Option) GT1020 Monochrome Touch Screen (Standard)

35 Optional Filtration

36 SiteControl/Smart Pump Pump Manager provides control of the pump via pressure and flow independently of the any remote system. Also, provides remote computer access to the pump. Smart Pump provides direct and real time communication between the pump station and the central control system Adjusts flow demand based on actual field conditions to maximize pump efficiency

37 Rain Bird Pump Stations Design Team Proposal packages with a standardized quotation are provided with 48 hours of completed requests. Drawings are available based on the most common configurations upon request. Factory Contacts Request for Quotation Alejandro Carrillo (520) Robbi Tolksdorf (520) Fax # (520) pumps@rainbird.com Sales & Marketing Tony Adamson (520) Herb Hofmann (602) Bill Wise (215) Product Manager Gordon Van Dyke (520) Pump Station Sales Team: (520)