Bus vs Line 3

[JetsKnicksYankees]

Quick Q.
What is the difference between Bus and Line? Would Bus be the transmission line entering a substation/switchyard and Line be the lower voltage cable inside the substation/yard?

 

[vandal06]

Bus would be the copper bus-bars connecting different pieces of equipment, such as circuit breaker and transformers, at a given energized voltage in the substation/switchyard.

 

[dpc]

The lines entering a substation are lines. The bus is what the other side of the breakers are connected to. The bus is the common connection point for all the incoming lines and sources. This will depend on the substation bus configuration - single bus, double bus, breaker and a half, ring bus, etc.

In some situation, the distinction between line and bus gets a little fuzzy and can depend on your perspective on the system.

Buses are nodes and Lines are branches if you are developing a model.

 

[rcw retired EE]

When programming Multilin relays like the 750 relay's undervoltage and synch check functions, check the VT input wiring. The settings for "BUS" apply to the VT connected to the "Bus VT" input terminals regardless if the voltage signal is from the bus or the outgoing feeder line.

The 25 synch check settings for "Live Bus-Dead Line", depend on which voltage input is wired to the VT terminals. It can get confusing, especially on a tie breaker or a generator breaker.

Other GE-Multilin relays allow specifying which VT input goes to Bus or Line.

 

[slavag]

rswilson, situation is more "problematic", if 25 function have a two buses and one line in application with double bus. Newer protective terminals are included such option with dynamic replica of disconnectors