WDB7 Series Surface Temperature Sensor

Replaced with ADB Lug Series 


The WDB7 series is a lug style NTC thermistor or platinum RTD (PT100) type for continuous temperature monitoring.  It is designed to bolt directly onto a bearing housing, motor, gearbox, machine casing or any other application where surface temperature monitoring is needed.


The mounting hole is 5/16” from the factory, but can be drilled up to 1/2” if needed.  The sensor 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 connections requirements are eliminated.



  WDB7 Surface Temperature Sensor  

• Surface Mount Installation


• NTC or PT100 RTD Versions


• Continuous Temperature Monitoring


• 5/16” to 1/2” Bolt Entry


• 1/2” NPT Conduit Entry

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  NTC Type Technical Specifications -   Literature:  
  • Resistance at 77 °F: 10,000 Ohms   Product Datasheet Download PDF  
  • Resistance at 140 °F: 3,043 Ohms      
  • Resistance at 194 °F: 1,264 Ohms   Technical:  
  • Sensing Voltage: 5 to 24 VDC   Product Manual Download PDF  
  • Current Draw: 1 mA      
  • Fixing Thread: 1/8" NPT   Product Dimensions:  
  • Minimum Temperature: -22 °F (-30 °C)   Download AutoCAD .dwg (AutoCAD)      Download PDF .pdf  
  • Maximum Temperature: 220 °F (105 °C)      
  PT100 RTD Type Technical Specifications -      
  • Resistance at 77 °F: 109.73 Ohms      
  • Resistance at 140 °F: 123.24 Ohms      
  • Resistance at 194 °F: 134.70 Ohms      
  • Coefficient: 3850 PPM/K (385)      
  • Sensing Voltage: 5 to 24 VDC      
  • Current Draw: 1 mA      
  • Fixing Thread: 1/8" NPT      
  • Minimum Temperature: -22 °F (-30 °C)      
  • Maximum Temperature: 220 °F (105 °C)      
  • CSA Class II Div 1 Groups E, F & G (U.S. & Canada)      
  CSA Certified         
  Part Numbers and Accessories:      
  • WDB70V3C ~ NTC Type      
  • WDB79V3C ~ PT100 RTD Type      
  Literature:   Product Dimensions:  
  Product Datasheet Download PDF   Download AutoCAD .dwg (AutoCAD)      Download PDF .pdf  
  Product Manual Download PDF      
  RTD Wiring Overview Download PDF      
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  Can the bolt hole be drilled out more than 1/2"?  
  It is not recommended to go beyond 1/2".  
WDB7 Surface Temperature Sensor
WDB7 Sensor Installed
Pillow Block Bearing Cut Away Diagram
Hot Bearing Failure
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