WDB1 & 2 Series Bearing Sensor


The WDB 1 & 2 series is a range of bearing sensors manufactured to screw directly into a bearing housing through the existing 1/8” NPT threaded grease zerk. Each sensor is fitted with a grease zerk to allow lubrication of the bearing without the need for removal of the sensor.


Three versions are available, a NTC thermistor or platinum RTD type for continuous temperature monitoring, and a PTC thermistor model with the following trip points (specify when ordering): 122°F, 140°F, 158°F, 176°F, 194°F.


The sensor is supplied with a nine foot attached cable and can be connected to a PLC or to a hazard monitoring system, such as 4B’s T500 Hotbus Elite, Watchdog Elite, or T400 Elite.


The connections are not polarity sensitive therefore special connection requirements are eliminated, and the cable can be extended in the field.



  WDB1 and 2 Series Bearing Temperature Sensors  

• NTC, PTC and RTD PT100 Versions


• Screws Into Existing Grease Zerk Location


• Integrated Zerk For Bearing Lubrication


• WDB1 - Brass Body (No Conduit Entry)


• WDB2 - 304 Stainless Steel Body (1/2" NPT Conduit Entry)

  Product Questions? (309) 698-5611Phone or Email  Email    
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  NTC Type Specifications:   Literature:  
  • Resistance at 77 °F: 10,000 Ohms   Product Datasheet Download PDF  
  • Resistance at 140 °F: 2,487 Ohms      
  • Resistance at 194 °F: 916 Ohms   Technical:  
  • Sensing Voltage: 5 to 24 VDC   WDB2 Product Manual Download PDF  
  • Current Draw: 1 mA      
  • Cable: 9 ft. (3 m)  2 Conductor   Product Dimensions (WDB2):  
      Download AutoCAD .dwg (AutoCAD)      Download PDF .pdf  
  PTC Type Specifications:      
  • Resistance at 140 °F: ≤ 250 Ohms      
  • Resistance at Trip Point: ≥ 2,000 Ohms      
  • Sensing Voltage: 5 to 25 VDC      
  • Current Draw: 20 mA      
  • Cable: 9 ft. (3 m)  2 Conductor      
  PT100 / RTD Type Specifications:      
  • Resistance at 32 °F: 100 Ohms      
  • Resistance at 212 °F: 138.4 Ohms      
  • Sensing Voltage: Via Transducer      
  • Current Draw: 1 mA      
  • Cable: 9 ft. (3 m)  4 Conductor      
  • WDB2 - CSA Class II Div 1 Groups E, F & G (U.S. & Canada)      
  • WDB1 - ATEX      
  CSA Certified  ATEX Certified  CE / European Conformity      
  Part Numbers and Accessories:      
  • WDB10V3AI - NTC Type (Continuous)      
  • WDB11V3AI - PTC Type (122 °F Trip)      
  • WDB12V3AI - PTC Type (140 °F Trip)      
  • WDB13V3AI - PTC Type (158 °F Trip)      
  • WDB14V3AI - PTC Type (176 °F Trip)      
  • WDB15V3AI - PTC Type (194 °F Trip)      
  • WDB19V3AI - RTD PT100 Type (Continuous)      
  • WDB20V3C - NTC Type (Continuous)      
  • WDB21V3C - PTC Type (122 °F Trip)      
  • WDB22V3C - PTC Type (140 °F Trip)      
  • WDB23V3C - PTC Type (158 °F Trip)      
  • WDB24V3C - PTC Type (176 °F Trip)      
  • WDB25V3C - PTC Type (194 °F Trip)      
  • WDB29V3C - RTD PT100 Type (Continuous)      
  Literature:   Product Dimensions (WDB2):  
  Product Datasheet Download PDF   Download AutoCAD .dwg (AutoCAD)      Download PDF .pdf  
  WDB2 Product Manual Download PDF      
  RTD Wiring Overview Download PDF      
Watchdog Super Elite Hazard Monitor

Watchdog™ Super Elite Hazard Monitor

The Watchdog™ Super Elite processes signals from sensors for belt misalignment, belt speed & slip, continuous bearing temperature, pulley misalignment and plug conditions for bucket elevators or belt conveyors.

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T500 Elite Hotbus Hazard Monitor

T500 Elite Hotbus™ Hazard Monitor

The T500 Elite Hotbus is a serial communications system designed to monitor up to 256 sensors on multiple bucket elevators and conveyors for belt speed, belt alignment, bearing temperature, level and plugged conditions.

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T400N Elite Hotswitch Temperature Monitor

T400N Elite Hotswitch

The T400N Elite Hotswitch is a microprocessor controlled temperature monitor, which works in conjunction with NTC type temperature sensors.  The unit can provide an alarm and automatic shutdown, on up to 2 machines, when a hot temperature condition is detected.

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  Are the probe depths adjustable on the WDB1 or WDB2?  
  No, only the ADB and Milli-Temp series have adjustable depth probes.  
WDB1 and WDB2 Bearing Sensor
Bearing Sensor Installed
Bearing Sensor Installation Diagram
Pillow Block Bearing Cut Away Diagram
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Hot Bearing Failure
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