Controls › Instrumentation
Level
Tank, wet well, and vessel level measurement.
Written guides in this section
Full references, procedures, and diagnostic guides published under Level.
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
Hydrostatic Level Measurement
Measuring level from the pressure of the liquid above a sensor: submersible transducers, bubblers, and base-mounted transmitters, the density assumption behind all of them, venting, installation, and what makes them drift.
8 min readUpdated Sep 5, 2026
Differential Pressure Level
Measuring level in a closed or pressurized vessel with a DP transmitter: high and low side connections, dry legs and wet legs, zero suppression and elevation, the range calculation with a worked example, remote seals, and the density dependence.
10 min readUpdated Sep 5, 2026
Float Switches
The oldest level instrument and still the one that saves a station: how tilt and stem floats work, the wiring conventions, mounting and spacing in a wet well, classified-area ratings, and how to use them alongside a continuous instrument.
7 min readUpdated Sep 5, 2026
Wet Well Level Measurement
How lift station wet well level is measured, which technology suits which well, the failure modes that flood a station, and why the high level float must stay hardwired.
8 min readUpdated Sep 5, 2026
Level Troubleshooting
A method for a level reading that is wrong, frozen, jumping, or lost: establish the true level, check the signal chain and configuration, then the checks for ultrasonic, radar, hydrostatic, DP, and float instruments, and the failure behavior to design in.
10 min readUpdated Sep 5, 2026
Topics in this area
Radar Level
Non-contact and guided-wave radar, and why it tolerates a wet well better than most alternatives.
Ultrasonic Level
Ultrasonic Level — practical reference notes for controls engineers, integrators, and technicians working with level.
Hydrostatic Level
Hydrostatic Level — practical reference notes for controls engineers, integrators, and technicians working with level.
Differential Pressure Level
Differential Pressure Level — practical reference notes for controls engineers, integrators, and technicians working with level.
Floats
Floats — practical reference notes for controls engineers, integrators, and technicians working with level.
Wet Well Level
The measurement that runs a lift station, and the failure modes that flood one.
Level Troubleshooting
Level Troubleshooting — practical reference notes for controls engineers, integrators, and technicians working with level.
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