Water Meters Review Flashcards

A comprehensive set of 150 vocabulary-style flashcards covering the types, applications, installation, and testing of water meters.

Meter Yoke

A special device that assists in the installation of small meters and helps protect them by holding stub ends in proper alignment.

Positive Displacement Meter

The most commonly installed water meter, used primarily for residential and small commercial applications.

Compound Meters

A combination of two meters (positive displacement and turbine) designed to accurately measure flow over a wide range.

Current Meter

A propeller or turbine type meter used for large industrial customers that continuously take large volumes of water.

Detector-check Meter

Used in applications where daily use is low, but an emergency condition like a fire suppression system may require high flow rates.

Turbine Meter

Uses a rotor turned by flowing water where revolutions are almost directly proportional to volume of flow; used in large flow applications.

Multijet Meter

Uses a multiblade rotor mounted on a spindle within a cylindrical measuring chamber.

Propeller Meter

Flowing water causes a propeller to rotate to record flow volume; used when flow is consistent and does not change abruptly.

Proportional Meter

Has a restriction in the pipe that requires a portion of flow to go through a meter and requires a multiplication factor to calculate actual flow.

Venturi Meter

A tapered constriction in the pipeline that creates a pressure differential depending on the rate of flow through it.

Orifice Meter

Features a thin plate that restricts flow and creates a differential pressure proportional to the flow rate.

Magnetic Meter

Utilizes a magnetic field and the principle that relative motion between a conductor (water) and a magnetic field will induce a voltage proportional to flow.

Ultrasonic Meter

Uses sound waves and the Doppler effect to measure flow frequency changes that are proportional to the flow rate.

Meter Yoke stub alignment

Holds the stub ends of the pipe in proper alignment to support the meter.

Meter Yoke spacing

Maintains proper spacing to support the installation of small meters.

Most common residential meter

Positive displacement meter.

Common industrial meter type

Current meter.

Fire suppression sprinkler system meter

Detector-check meter.

Large flow rotor meter

Turbine meter.

Multijet Meter rotor mounting

Mounted on a spindle within a cylindrical measuring chamber.

Consistent flow meter

Propeller meter.

Multiplication factor meter

Proportional meter.

Pressure differential constriction meter

Venturi meter.

Thin plate restriction meter

Orifice meter.

Voltage induced flow meter

Magnetic meter.

Doppler effect meter

Ultrasonic meter.

Customer metering monitoring

Used for billing and monitoring for watering loss.

Meter type determination factors

Volume and rate of usage.

Types of positive displacement meters

Piston and Nutating-disc.

Positive Displacement wear effect

Wears over time and reads lower than actual flow.

Large-Customer Meter Options

Compound meters, current meters, and detector-check meters.

Compound meter usage criteria

Used when volume and flow vary widely.

Parts of a standard compound meter

Turbine meter, positive displacement meter, and automatic valve arrangement.

Turbine meter role in compound meter

Measures volume during high flow rates.

Positive displacement role in compound meter

Measures volume during low flow rates.

Current meter alternative name

Velocity meters.

Current meter accuracy limit

Accuracy drops significantly in the lower end of the meter's limit.

Protection for current meters

Good practice to place a strainer prior to the meter to protect from sediment.

Detector-check daily use meter type

Water usage is normally metered by a positive displacement type meter.

Detector-check fire flow condition

Water bypasses the meter to meet high demand.

Meter sizing factor: Demand

Expected maximum demand.

Meter sizing factor: Pressure

Normal system pressure.

Meter sizing factor: Friction

Friction losses in the line.

Meter sizing factor: Range

Range of flow rates expected.

Residential meter size range

$5/8$ or $3/4$ of an inch.

Commercial meter sizes

$1$, $1\frac{1}{2}$, or $2$ inches.

Commercial PD meter flow capacity

$5\%$ to $35\%$ of the meter's rated capacity.

Turbine meter large capacity requirement

Used if flow is $> 10\%$ of the maximum rating.

Indoors installation climate

Preferred for cold climates.

Outdoors installation climate

Preferred for warm climates.

Indoor installation location

Located where the pipe first enters the building.

Indoor installation accessibility

Must be accessible for reading or repair.

Ground across meter requirement

Required if the electrical system uses plumbing as a ground and no meter yoke is used.

Outdoor meter property location

Locate on public property if possible.

Outdoor meter traffic precaution

Locate away from vehicle traffic.

Outdoor meter box lid fit

Box lid must fit tightly and be flush with the ground.

Frost protection piping gap

Piping should be $1-2$ inches away from the meter box side.

Large meter support requirement

Properly supported so as not to put stress on water piping.

Large meter vault workspace

Must have adequate work space.

Large meter vertical wall clearance

$20$ inches.

Large meter head space

$24$ inches.

Volumetric test equipment

Test valves installed for volumetric tests.

Thrust blocking for meters

Installed as required for large meter installations.

New meter testing timeframe

Before installation.

Representative sampling

Used for testing new meters in most states.

Meter registration over time

Meters will register lower than actual flow as they age.

National testing frequency standard

No national testing frequency standard exists.

Testing Procedure basis

A known volume of water is passed through several different flow rates.

Small PD meter testing ranges

Maximum, Intermediate, and Minimum.

Large meter testing flow rates

Four or five different flow rates are tested.

Large meter testing location

Typically tested in the field.

Field testing range limit

Only the lower $5\%$ to $10\%$ of the range is tested.

Velocity meter size threshold

Usually installed on water lines that are $3$ inches or more in diameter.

Major current meter subtypes

Turbine, Multijet, and Propeller.

Turbine rotor location

Rotates within a measuring chamber.

Turbine flow requirement

Requires a minimum flow rate.

Turbine friction loss

Very little friction loss within the meter.

Turbine sediment effect

Will under register if sediment accumulates on blades.

Multijet water entry

Water enters through many orifices around the circumference.

Clogged Multijet performance

Will over register.

Worn Multijet performance

Will under register.

Propeller pipe diameter coverage

Propeller does not take up the entire diameter of the pipe.

Proportional meter friction loss

Minimal friction loss.

Proportional meter accuracy

Generally accurate and provides minimal friction loss.

Venturi pressure conversion

Pressure compared and converted by mechanical or electronic instrumentation.

Venturi advantage: Maintenance

Requires very little maintenance.

Venturi advantage: Loss

Minimal friction loss.

Orifice plate thickness

Thin plate.

Orifice disadvantage

The head loss produced.

Orifice main advantage

Low cost.

Magnetic meter principle conductor

Water acts as the conductor.

Magnetic meter induction

Relative motion between water and a magnetic field induces a voltage.

Magnetic meter voltage proportion

Voltage produced is proportional to flow.

Magnetic meter suitability: Water quality

Well suited for applications involving dirty or corrosive water.

Magnetic meter head loss

Causes very little head loss.

Ultrasonic sensors

Use transducers to send and receive sound waves.

Ultrasonic frequency proportionality

Frequency change is proportional to the flow rate.

Piston Meter Category

Type of positive displacement meter.

Nutating-disc Category

Type of positive displacement meter.

Compound valve arrangement

Automatic valve arrangement used to direct flow between meters.