Selecting Continuous Level Sensors

SmartBob Weight & Cable

Strengths

•  Not affected by dust or other adverse process conditions 
•  Not affected by material buildup on sensor
•  Can be used in extremely light, signal-absorbing materials
•  Measures bins up to 180 feet (SmartBob-TS1 up to 60 feet)
•  Not affected by material characteristics such as low dielectric constant or angle of repose 
•  Remote sensor requires no calibration 
•  High temperature models available up to 1000°F 
•  Very simple setup and installation 
•  Consistent, repeatable, and accurate measurements
•  Compatible with eBob software
•  A variety of digital and analog outputs available 
•  Cable replacing, wireless communications available
•  Hazardous location approvals available

Considerations

•  On-demand system, does not provide an instantaneous response to change in the material level
•  Seasonal maintenance may be required to clean out mechanical cavity in very dusty conditions, if air-purge is not used 
•  Not recommended in high pressure bins
•  Minimal contact with stored material

GWR-2000 Guided Wave Radar

Strengths

•  Continuous level measurement in powders, granules, bulk solids, and liquids
•  Measuring distance up to 100 feet
•  For light to heavy bulk solids
•  4-20 mA and Modbus RTU communications
•  Performs in vessels prone to high dust
•  Suitable for vessels of most any shape or diameter, including narrow tanks
•  Immune to condensation
•  Virtually maintenance free
•  Reliable accuracy within 0.08”
•  Hazardous location approvals
•  BinDisc simple setup and configuration
•  Compatible with eBob software
•  Very simple setup and installation
•  Cable replacing, wireless communications available

Considerations

•  Sensing probe is in constant contact with material
•  Minimum dielectric constant of material must be above 1.3
•  Material like large rock may damage probe and be difficult to sense

3DLevelScanner Acoustic

Strengths

•  Continuous level measurement 
•  Non-intrusive, non-contact design 
•  Measures uneven powder or solid material surfaces 
•  Detects cone up, cone down and sidewall buildup
•  Provides minimum, maximum and average distances 
•  Performs in extreme levels of dust 
•  Calculates highly accurate bin volume due to mapping the surface of the material with multiple measuring points. 
•  Measuring range up to 200 feet 
•  Self-cleaning with minimal maintenance
•  High temperature applications up to 365°F 
•  Automatic compensation for temperature changes 
•  Analog and digital communication options 
•  Leading-edge 3D MultiVision networkable PC software available for multiple vessel monitoring
•  Can generate a 3D image of material surface 
•  Cable-replacing, wireless interfaces available
•  Approved for hazardous locations
•  Not affected by material characteristics or low dielectric constants
•  RL model compatible with eBob software

Considerations

•  The 3DLevelScanner is an acoustic device and elevated background noise can have an affect on its performance
•  Setup requires care in mounting the sensor in the proper location, and mapping the vessel 
•  Time required to process multiple pulse echoes limits the sample rate
•  Not recommended for liquid applications
•  Corrugation on small vessels can cause false echoes
•  Not recommended for materials with a bulk density under 11 lb./cu. ft. due to absorbing the acoustic pulse  

LL-100 Laser Level Sensor

Strengths

•  Measures in a very tight 1° beam with no beam divergence 
•  Accuracy of +/- 1 inch with range up to 160 feet
•  Can track during fill in low dust environments
•  Ideal for very narrow vessels or constrained spaces
•  Unaffected by corrugated bin walls
•  Can be precisely targeted to avoid structure inside vessel
•  Use for plugged chute detection or monitoring sidewall buildup 
•  Versatile for bulk solids, pellets, granular materials, and opaque liquids
•  Can be used in most any dielectric material
•  Unaffected by heavy vapors and pressure
•  Adjustable 10° mounting flange for precise aiming
•  Integrated dust protection for minimal maintenance
•  Easily configured in the field using a USB port
•  Configuration can be performed without filling or emptying vessel

Considerations

•  Single point measurement will not take into account material topography
•  Laser will penetrate clear liquids
•  Dusty environments will diminish performance
•  Air purge may be required to keep lenses clean in dusty environments

NCR-80 Non-Contact Radar for Solids

Strengths

•  Powerful 80 GHz radar significantly outperforms old 26 GHz technology
•  4° versus 10° beam angle for better precision and targeting
•  Substantial 393 foot measuring range
•  Same sensor technology used by self-driving cars
•  Strong signal performs well in dust
•  Fast reaction/update time tracks filling or emptying activity
•  Versatile for use in solids, liquids, and slurries
•  Signal not affected by corrugation
•  Loop power capability
•  Compatible with eBob software
•  4 - 20 mA and Modbus RTU communications

Considerations

•   Single point measurement will not take into account material topography
•   Minimum dielectric constant of material must be above 1.3