How does a generator connect to a synchronizing bus?

• A. Through a transfer switch
• B. Through a bus tie breaker
• C. Through a circuit breaker
• D. Directly connected to the main bus

Answer: (B)

Paralleling a generator with a synchronizing bus is done through a bus tie breaker, which creates a controlled connection between two bus sections so multiple power sources can share the same bus. After the generator’s output is synchronized (voltage, frequency, and phase matched), the bus tie breaker is closed to join the generator’s bus to the synchronizing bus, allowing proper load sharing while keeping protection and isolation available when needed. This device is specifically intended for connecting or disconnecting generators from the common bus; other options either switch entire sources or bypass the proper interconnection, which isn’t how parallel operation is safely achieved.