Siemens HydroRanger 200 HMI, Руководство по эксплуатации

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Diagnosing and troubleshooting
10.6 Fixed reading
HydroRanger 200 HMI
290
Operating Instructions, 06/2018, A5E36281317-AC
10.5.1.3 Install a transducer with a narrower beam
A consistently incorrect level reading may be due to interference echoes from the sides of a
vessel. If this occurs, try installing a longer range (narrower beam) transducer, enter the new
transducer model, and (if necessary) optimize aiming and frequency again.
Always contact Siemens service personnel before selecting a transducer to solve this type of
problem.
10.6 Fixed reading
If the Reading is a fixed value, regardless of the transducer to material surface distance,
ensure the:
● Transducer acoustic beam is free from obstruction.
● Transducer is properly aimed
● Transducer is not in contact with any metal object.
● Material mixer (if used) is operating while the device is operating. If it is stopped, ensure
that the mixer blade is not stopped under the transducer.
10.7 Obstructions in the sound beam
Check for (and remove if present) any acoustic beam obstruction, or relocate the transducer.
If an obstruction cannot be removed or avoided, adjust the Time Varying Threshold (TVT)
curve to reduce the Echo Confidence derived from the sound reflected by the obstruction.
Use SIMATIC PDM to adjust the TVT curve.
10.8 Nozzle mountings
If the transducer is mounted on or in a nozzle, grind smooth any burrs or welds on the inside
or open end (the end that opens into the vessel). If the problem persists, install a larger
diameter or shorter length nozzle, bevel the inside of the bottom end, or cut the open end of
the nozzle at a 45° angle.
See the transducer manual for complete mounting instructions.
If the mounting hardware is over tightened, loosen it. Over tightening changes the resonance
characteristics of the transducer and can cause problems.