Identify what the display represents
Record model, alarms, units, displayed variable and the reading over time. Instantaneous flow, a totaliser and a control-system calculation are different values. A totaliser retaining its historical value does not mean flow continues. Record positive or negative readings and timing rather than sending only one screenshot.
A closed valve is not proof of zero flow
Use existing operating records and process information to review bypasses, recirculation and possible valve leakage. Do not operate valves independently for this check. For liquid service, site personnel must also establish whether the tube is full, gas or phase changes are present, and temperature and pressure are stable.
Look for process and configuration clues
Observe whether the symptom coincides with pump operation, nearby vibration or process changes. Review direction, units, damping and low-flow cutoff through existing screens or configuration records. A cutoff may affect small displayed values; it does not establish that the underlying cause has been removed.
- Record flow, density, temperature and alarms during the apparent no-flow period.
- Keep existing configuration and recent change records for comparison.
When to involve an engineer
Refer persistent offset, alarms or uncertain no-flow/filling conditions to an engineer, who can determine whether zero verification or calibration is appropriate under the model's manual. This page is for observation and document checks, not field zeroing instructions. Opening covers, wiring, pipe removal, pressurised work and hazardous-area tasks require site procedures.
