1. 
   b contact
   a control or auxiliary contact which is open when the main contacts of a mechanical switching device are closed and closed when they are open
   Found op http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=441-15-13
   
   
2. 
   b-contact
   a control or auxiliary contact which is open when the main contacts of the circuit-breaker or contactor are closed and closed when they are open
   Found op http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=442-05-32
   
   

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