A bus, or busbar, is a bar, tube or node to which incoming supplies and outgoing feeders connect, usually copper or aluminium carried on insulators. Substation layouts are named by their bus arrangement: single bus, double bus, main and transfer, ring bus, breaker-and-a-half. In network studies a bus is any node with a voltage, so a load-flow model counts buses rather than physical bars.
Both transformers are on the 11 kV bus with the coupler closed, open it and each half carries its own load.
Also heard as
- busbar
- bus bar
Related terms
Switchgear
Assemblies of breakers, switches, fuses, busbars and enclosures that control and protect power circuits.
Dead bus
Busbar with no voltage on it, the condition that lets a breaker close without synchronising checks.
Differential protection
Scheme that compares current entering and leaving a protected zone and trips when the two disagree.