“Draw a feeder distribution single line diagram for a 480 V industrial plant with two 2500 kVA transformers, two 3200 A mains, a normally open tie breaker, and feeders for an MCC, process line, and plant utilities.”
Entenda as decisões por trás dele.
Two 2500 kVA sources supply independent 480 V bus sections.
The 3200 A tie permits a controlled transfer without paralleling sources.
A dedicated 800 A feeder serves motor control equipment.
The high-demand process line is fed from Bus A.
Plant utilities stay on the separate Bus B section.
Use this for a medium industrial facility needing maintainable LV distribution. Protection settings, source impedance, and transfer interlocking need coordination studies.
Dúvidas comuns
Why is the tie breaker normally open?
It keeps the transformer sources separated during ordinary operation while preserving a transfer path.
Can one transformer carry both buses?
Only if its loading, protection, and the transfer procedure have been engineered for that condition.
What is an MCC?
A motor control center groups starters and protective devices for multiple motors.