The distribution of electricity between power plants, utility companies and households is possible thanks to one extremely important component. While this component is one of many, its role is far greater than any other electrical component when it comes to power distribution. Electrical busbars are metallic strips of copper, aluminium or brass that help both conduct and ground electricity. They’re like a 2 in 1 solution that ensures electricity flows safely from one place to another.
A power busbar can be found at base stations, in power switch systems, power generations systems, power conversion modules of electric equipment, telephone exchange systems and more. Busbars work by simply being a conductor, conducting power to the outgoing feeders. They act like an electrical junction box where both outgoing and incoming currents meet. But although the task of a busbar is simple, they come in different arrangements, making them suitable for different applications.
Types of Busbar Arrangements
Single
Starting from the simplest power busbar arrangement there is, a single bus-bar arrangement consists of one switchboard and one bus. The advantage of these popular insulated busbars is that they require less maintenance and they are more affordable while being simple and easy to operate. The downside of using a single bus-bar arrangement is that if there are any faults, the whole power distribution is interrupted. A single bus bar arrangement is also less flexible since it is only used in small power stations and switchboards.
Single With Sectionalisation
A step up from a single bus arrangement is a single bus arrangement with a sectionalised bus. What this means is that the isolator in the arrangement is used to separate the faulty section to keep the system from shutting down completely. This makes it easy to remove the faulty section without any loss in the supply continuity. Another advantage of single bus arrangements with a sectionalised bus is that the current-limiting reactor helps reduce the faults in the sections of the bus. The downside of this arrangement is that it uses additional isolators and circuit breakers which increase its cost.
Main & Transfer
A main and transfer bus arran gement is made to combine an auxiliary type and the main bus bar thanks to a bus coupler. The bus coupler connects the circuit breaker and isolated switches, and in case of overloading, the load is transferred from one bus to the other. The benefit of using these types of insulated busbars is that their relays can be operated by the bus potential.
The cost of repair, as well as maintenance, is low too. It’s also easy to shift the load on any other buses. The downside of a main and transfer arrangement is that the whole system may break down if any fault occurs in any of the sections of the bus. Also, the cost of this arrangement is higher since the system uses two bus bars.
Double Bus Double Breaker
A double bus double breaker arrangement is one that has two circuit breakers. This means there is no special equipment required like a bus coupler or a switch. This type of arrangement gives you reliability and flexibility that isn’t present on any other bus arrangement without a loss of continuity. Despite the load being transferred from one bus to another, there is no change in the supply continuity. One downside you will find with this type of arrangement is that it has a high cost up front, as well as a maintenance cost, due to the use of additional circuit breakers and two buses.
Sectionalized Double Bus
Like a main and transfer arrangement, a sectionalised double bus arrangement uses an auxiliary bus along a sectionalised main bus bar. Any section of the main type arrangement can be taken out for repair and maintenance, and it can also be connected to any of the auxiliary bus bars. With this type of arrangement, there is no need to sectionalise the auxiliary type.
One and a Half
With a one and a half breaker arrangement, you get a system with 4 circuit breakers for 2 circuits. This means that each circuit uses a ½ circuit breaker, making this setup useful in large stations. The advantage of this type of arrangement is that it protects the system against a loss of power supply. It can also be used to operate relays and the arrangement makes it easy to add additional circuits to the system. The downside of a one and a half breaker arrangement is that it has a high maintenance cost and a complex circuit because of the relay system.
Conclusion
Electrical busbars are the backbone components in many electrical applications, be it big or small. This is the main reason why there are many different arrangements. No matter the arrangement though, you must always adhere to proper use and implementation of busbars, as this guarantees safety and a well-performing system too.
The Australian Expert 