Controls › Instrumentation
Flow
Measuring flow in pipes and open channels.
Written guides in this section
Full references, procedures, and diagnostic guides published under Flow.
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
Magnetic Flowmeters
Faraday's law applied to a pipe: how a mag meter works, the conductivity and full-pipe requirements, and why grounding decides whether it reads.
8 min readUpdated Aug 1, 2026
Topics in this area
Magnetic Flowmeters
How a mag meter works, where it fits, and the conductivity and grounding rules that decide whether it reads.
Ultrasonic Flow
Ultrasonic Flow — practical reference notes for controls engineers, integrators, and technicians working with flow.
Differential Pressure Flow
Differential Pressure Flow — practical reference notes for controls engineers, integrators, and technicians working with flow.
Open Channel Flow
Open Channel Flow — practical reference notes for controls engineers, integrators, and technicians working with flow.
Flow Installation
Flow Installation — practical reference notes for controls engineers, integrators, and technicians working with flow.
Flow Troubleshooting
Flow Troubleshooting — practical reference notes for controls engineers, integrators, and technicians working with flow.
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