Single Bus bar arrangement
In a single bus bar scheme, there is no any duplicate busbar, only one single bus bar is used.In this scheme, the generators, feeders, transformers are connected to busbar through isolator switches and circuit breakers which are shown in the figure.
The advantage and disadvantage of single busbar system are given below.
Advantage:-
- It is the cheapest installation as only one circuit breaker for each outgoing circuit is required.
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Due to the absence of the transfer bus breakers and disconnector, the operation has become simple.
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It is possible to utilize the busbar potential for the line relays.
Disadvantage :
- In the case of a busbar fault, the complete shutdown is required which is the biggest disadvantage of the single Bus- Bar system.
- It is not possible to any regular maintenance work on the energized busbar.
- Due to the absence of transfer bus bay, failure of a breaker on the circuit, that circuit cannot get the power from the bus until the circuit breaker rectified or new circuit breaker installed.
**Single bus bar system is used for d.c Sub-Station and small a.c Sub-Station where minimum maintenance is required.