The Transfer Operation


The main and transfer bus arrangement does not provide bus-bar redundancy, the transfer bus is a mechanism to ‘transfer’ the operation of a circuit to a transfer breaker, releasing the circuit breaker for maintenance or repair to be done. But if the main bus-bar fails, we run out of system.

The safety criteria for this transfer operation are:

  • Never have a section energized if it is not necessary.
  • The connection operation between energized and non-energized sections must always be carried out with a breaker operation (not with a disconnector operation)

The disconnector can be used if the above is not feasible only to join an energized section with a short de-energized section, for example a connection between disconnector and its circuit breaker, but not a transfer bus.

This disconnector operation will generate a low intensity electric arc in the final closing phase of the disconnector.

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