Distribution System Meters - American Water College ?· Picture from Water Distribution System Operation…

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  • Meters

    American Water College 1

    American Water College

    Distribution Review

    Water Meters

    American Water College

    Water Meter Training Objectives

    To gain an understanding of:

    The construction and operation of the different types of water meters

    The normal application of the various water meters

    American Water College

    Water Meters

    Types:Positive-displacementCompound

    CurrentProportional

    Venturi OrificeMagnetic

    Sonic

  • Meters

    American Water College 2

    American Water College

    Positive Displacement Water Meter

    Most common type of meterTwo types:

    Pistonpiston moves back and forth as water passesa known volume is measure for each cyclemotion is transmitted to the register througha magnetic drive and gears

    Nutating-discmeasuring chamber contains flat discwater flow causes disc to wobble and rotaterotation is transmitted to register which records volume that passed through

    American Water College

    Positive Displacement Water Meter

    Used for residential metering

    Not intended for continuous flow

    As positive displacement meters age and wear, they will measure less flow than actually passes through the meter.

    They should be calibrated on a 10 year cycle.

    American Water College

    Positive Displacement Water Meter

    Nutating Disc

  • Meters

    American Water College 3

    American Water College

    Positive Displacement Water Meter

    Piston type

    Picture from Water Distribution System Operation and MaintenanceFourth Edition published by the Office of Water Programs, CSUS.

    American Water College

    Current Water Meters

    Used for large industrial customers

    Commonly called velocity metersThree main types:

    turbinerotors turned by flow revolutions are proportional to flow

    multi-jetsimilar to turbine but has multi-blade rotor

    propellerpropeller turned by flowrevolutions are proportional to flow

    American Water College

    Current Water Meters

    Picture from Water Distribution System Operation and MaintenanceFourth Edition published by the Office of Water Programs, CSUS.

    Propeller Meter Turbine Meter

  • Meters

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    American Water College

    Compound Water Meters

    Used for customers with wide variations in flow

    Accurate over a wide range of flowThree main parts:

    turbine meter

    positive displacement meterautomatic valve arrangement

    During periods of low flow, water flows through positive displacement meterAs flow increases, the valve opens and allows flow through turbine meter

    American Water College

    Compound Water Meters

    Picture from Water Distribution System Operation and MaintenanceFourth Edition published by the Office of Water Programs, CSUS.

    American Water College

    Proportional Water Meters

    Principle of operation:

    Proportional meters have an orifice which restricts flow and forces a portion of flow through the meter

    Total flow is determined by reading the meter and multiplying the reading by a factor.

  • Meters

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    American Water College

    Proportional Water Meters

    American Water College

    Venturi Water Meters

    Principle of operationCross sectional area of flow path is reducedVelocity increases while pressure goes down

    Pressure is measured at two pointsprior to reduction in areaat the throat of the venturi (narrow point)

    Differential pressure is proportional to flow

    American Water College

    Venturi Water Meters

    Higher Pressure

    Lower Pressure

  • Meters

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    American Water College

    Orifice Water Meters

    Principle of operation:Orifice plate is inserted into the pipe

    Pressure is measured on both sides of the orifice

    Pressure difference is proportional to the flow

    Causes high head loss

    American Water College

    Orifice Water Meters

    American Water College

    Magnetic Water Meters

    Principle of operation:

    A conductive material flowing through a magnetic field will induce a voltage

    A magnetic field is established across the pipe

    The higher the flow, the higher the voltage

    Voltage is proportional to flow

    Often used in dirty or corrosive applications

  • Meters

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    American Water College

    Magnetic Water Meters

    In Line Meter Insertion type Meter

    American Water College

    Sonic Water Meters

    Principle of operation:Ultrasonic sound waves are transmitted through the pipe and across the flowing water.

    Doppler effect caused by the flowing water is measured and is proportional to the flow.

    American Water College

    Review the lecture handout and then complete the quiz. This will help you

    remember the information we just covered.