Power Plant Construction and QA/QC

Section 4.4 – In-Plant Electrical Distribution

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Section 4.4 – In-Plant Electrical Distribution

Overview

• Loads vary – 5v to 13.8 kV

• Vital and Non Vital loads

• Both AC and DC voltage

• Multiple Power Sources – Battery, Emergency Generators

• Protection

• Voltage

• Current

• Faults

• Shorts

• Connection – Wire and bus trays

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Section 4.4 – In-Plant Electrical Distribution

Power Plant Distribution - Concept

Source 1

Transformer

Switchgear

Load Center

Vital Load Center

Transformer

Transformer

Source 2

Transformer

Switchgear

Load Center

Transformer

Source 3

13.8 kVTo

1,460 VTo

480 Vto

120 V

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Section 4.4 – In-Plant Electrical Distribution

Power Plant Distribution

Transformer

Switchgear

Equipment

SourceStorage

Bus Bars

Bus Bars

Wires

Wires

Wires

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Section 4.4 – In-Plant Electrical Distribution

Power Plant Distribution

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Section 4.4 – In-Plant Electrical Distribution

Switchgear – Circuit Breakers

Installed 13.8 kV Circuit Breaker Removed

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Section 4.4 – In-Plant Electrical Distribution

Switchgear – Circuit Breakers

Front 480 V Circuit Breaker Back

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Section 4.4 – In-Plant Electrical Distribution

Switchgear – Circuit Distribution

Circuit Breaker

Fuse

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Section 4.4 – In-Plant Electrical Distribution

Switchgear Bus Work

Internal

External

4,160 and 13,800 Volts

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Section 4.4 – In-Plant Electrical Distribution

Cable Trays 480 / 240 and 120 Volt

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Questions?

Section 4.4 – In-Plant Electrical Distribution