|  | 
                Ballast | 
                An auxiliary electrical device for fluorescent
                and other discharge light sources. 
                  | 
            
              |  | 
                Battery | 
                A device for turning chemical energy into
                electrical energy. 
                  | 
            
              |  | Bonding (Bonded) | The permanent joining of metallic parts to form an electrically conductive path that ensures electrical continuity and the capacity to conduct safely any current likely to be imposed.   | 
            
              |  | Bonding
                Bushing | A
                conduit bushing that has conductor terminal use to bond the
                conduit.   | 
            
              |  | Bonding Jumper | A reliable conductor to ensure the required electrical conductivity between metal parts required to be electrically connected.   | 
            
              |  | Booster | A
                generator inserted in series in a circuit to add or subtract
                from the circuit voltage.   | 
            
              |  | Branch Circuit | The circuit conductors between the final overcurrent device protecting the circuit and the
                outlet(s).   | 
            
              |  | Breaker
                Tie | A
                metal device used to connect one or more circuit breaker handles
                so that they switch at the same time. 
                  | 
            
              |  | 
                BTU | 
                British Thermal Unit. Energy required to raise
                one pound of water one degree Fahrenheit. One pound of water at
                32 degrees F requires the transfer of 144 BTUs to freeze into
                solid ice. 
                  | 
            
              |  | 
                Buck-Boost Transformer | 
                A small, low voltage transformer placed in
                series with the power line to increase or reduce steady state
                voltage. 
                  | 
            
              |  | Building | A structure that stands alone or that is cut off from adjoining structures by fire walls with all openings therein protected by approved fire doors.    | 
            
              |  | 
                Busbar | 
                A heavy rigid conductor used for high voltage
                feeders. 
                  | 
            
              |  | BX | 
                A nickname for armored cable. 
                  |