Controls
Instrumentation
Flow, level, pressure, and analytical measurement — selection, installation, signals, and calibration.
Written guides in this section
Full references, procedures, and diagnostic guides published under Instrumentation.
Ultrasonic Flowmeters
Transit-time and Doppler ultrasonic flow measurement: how each works, which liquids each suits, clamp-on versus wetted transducers, the pipe data the meter needs, the accuracy to expect, and the installation details that decide whether to trust the reading.
10 min readUpdated Sep 5, 2026
Differential Pressure Flow Measurement
Orifice plates, venturis, and flow nozzles: the square-root relationship, why turndown is limited, where the square root is taken, impulse line rules, and when a DP element is still the right choice against a mag meter.
10 min readUpdated Sep 5, 2026
Open Channel Flow Measurement
Flumes and weirs with a level sensor: how the head-discharge relationship works, Parshall flume and weir equations, where to put the sensor, submergence, and the errors that make a permit-reporting flow meter wrong.
11 min readUpdated Sep 5, 2026
Flowmeter Installation
The installation rules that decide whether a flowmeter reads correctly: straight run by meter type, keeping the pipe full, orientation, velocity range, grounding for magnetic meters, isolation and access, and the commissioning checks that prove the meter.
10 min readUpdated Sep 5, 2026
Flow Troubleshooting
A method for a flow reading that is wrong, noisy, zero, or disputed: establish the truth with an independent check, separate installation from configuration from signal chain, then the specific checks for magnetic, ultrasonic, and DP meters.
10 min readUpdated Sep 5, 2026
Ultrasonic Level Measurement
Non-contact level by time of flight: how the sensor works, the blanking zone and beam angle, temperature compensation, the surfaces and vapors that defeat it, mounting rules, and what to do when it loses its echo.
8 min readUpdated Sep 5, 2026
Topics in this area
Flow
Measuring flow in pipes and open channels.
6 topics
Level
Tank, wet well, and vessel level measurement.
7 topics
Pressure
Gauge, absolute, and differential pressure measurement.
5 topics
Analytical
Water quality instrumentation and the maintenance it demands.
8 topics
Signals
What actually travels on the wire, and what corrupts it.
8 topics
Calibration
Proving an instrument reads correctly and recording that you did.
4 topics
Direct contact
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References to manufacturers, products, model numbers, software platforms, technical specifications, companies, standards organizations, or other organizations are provided for informational purposes and do not imply sponsorship, endorsement, authorization, or affiliation unless expressly stated. Manufacturer specifications must be independently verified against current manufacturer documentation.