Installation of LR460 Silo and Ref Bin Level Gage

Note: for best results, install when the silo or bin has just enough material to fill the bottom cone and the infeed belt is running.

  1. Mount and wire the unit (don’t forget the dust cap) and aim it pointing straight downward at first.
  2. Perform the quick-start procedure on the following page.
  3. Change parameter 3.5.2.1 Echo Algorithm to “AL”. This allows the gage to track the echo that’s the largest and has the most area under its curve.
  4. Go to parameter 3.6.2.2Echo Strength. Loosen the six swivel-aimer mounting bolts and aim the unit for maximum signal.
  5. You may need to make modifications to the quick-start parameters (ie the zero and span). Remember to “apply changes” (parameter 1.8)
  6. Go to parameter 3.2.6.1 Echo Confidence Long. This is the “quality” of the reading. There’s a minimum confidence threshold allowable, set by parameter 3.5.2.2 Echo Threshold Long. If the echo confidence drops below this, the LOE timer (3.5.1.1) starts timing – if it times out, the gage goes into fail safe mode (parameter 4.3.6, usually set to “hold last”). You might need to lower the Echo Threshold Long (Parameter 3.5.2.2). It is not unusual to set this around “5” for a coal silo.
  7. Perform auto-false echo suppression: estimate the distance from the gage face to the material; divide by two and enter this value in 3.5.6.2 Range (Auto False Echo Supression Distance). Then go to 3.5.6.1 Auto TVT and change to “Learn”. After a few seconds, this value automatically reverts to “ON”.
  8. Check the echo profile with the PDM software package. Take a screen shot if the echo profile and paste it to an MSWord document for reference.
  9. Some other parameters you might need to adjust:

Near Range – 3.5.4.1. The range in front of the device within which all echoes are ignored. The unit shown below has a near zone setting of 7 ft

TVT Hover Level – 3.5.6.3. Defines, in percent, how high the TVT curve is placed above the largest echo. Default is 40%.

Data and a screen shot of a start-up on a 135 ft tall silo:

Confidence = 26, signal = 47 dB, performed AFES with dist set to 50 ft (actual level approx 100 ft away). Set min threshold (parameter 3.5.2.2) at 6dB. Set output to 0-100% (was 0-35%) from 0-125 ft (was 0-135 ft). Increased TVT hover level from 30% to 45%, re-did AFES with D=50 ft. changed near range to 7 ft to ignore false target close to gage. Final settings on following pages.