vault backup: 2025-10-16 16:08:33
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@@ -21,8 +21,8 @@ The frequency of the AC power grid in the United States is 60 Hz.
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## 3-Phase Power
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The conductors between a voltage source and a load are called lines,
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and the voltage between any two lines is called line voltage.
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The voltage measured between any line and neutral is called phase voltage.
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and the voltage between any two lines is called **line voltage**.
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The voltage measured between any line and neutral is called **phase voltage**.
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* Poles vs Phases vs Wires
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@@ -34,16 +34,24 @@ The voltage measured between any line and neutral is called phase voltage.
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> * Φ (capital phi)
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> * Ø (latin O with stroke)
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208Y/120V
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480Y/277V
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### Formula
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In a 3-phase wye connected system,
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ignoring the difference in voltage,
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is voltage drop calculated differently
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between a line to line load and a line to neutral load
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$$
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P = \sqrt{3} \times V_{L} \times I_{L} \times PF
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$$
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where:
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* $P$ is the power in watts,
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* $V_{L}$ is the line voltage,
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* $I_{L}$ is the line current,
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* $PF$ is the power factor.
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### Voltage Systems
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208Y/120V
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480Y/277V
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120/240V 1-Phase 3-Wire:
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* 120V 1-Phase 2-Wire # Line to Neutral
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* 240V 1-Phase 2-Wire # Line to Line
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@@ -8,9 +8,9 @@ tags:
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- status/incomplete
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- topic/electrical
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- type/media
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title: Article 314 Outlet, Device, Pull, and Junction Boxes; Conduit Bodies; Fittings; and Handhole Enclosures
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title: "Article 314: Outlet, Device, Pull, and Junction Boxes; Conduit Bodies; Fittings; and Handhole Enclosures"
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---
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# Article 314 Outlet, Device, Pull, and Junction Boxes; Conduit Bodies; Fittings; and Handhole Enclosures
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# Article 314: Outlet, Device, Pull, and Junction Boxes; Conduit Bodies; Fittings; and Handhole Enclosures
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## Part I. Scope and General
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@@ -8,9 +8,9 @@ tags:
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- status/incomplete
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- topic/electrical
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- type/media
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title: Article 430 Motors, Motor Circuits, and Controllers
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title: "Article 430: Motors, Motor Circuits, and Controllers"
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---
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# Article 430 Motors, Motor Circuits, and Controllers
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# Article 430: Motors, Motor Circuits, and Controllers
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## Part I. General
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@@ -8,9 +8,9 @@ tags:
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- status/incomplete
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- topic/electrical
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- type/media
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title: Article 450 Transformers and Transformer Vaults (Including Secondary Ties)
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title: "Article 450: Transformers and Transformer Vaults (Including Secondary Ties)"
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---
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# Article 450 Transformers and Transformer Vaults (Including Secondary Ties)
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# Article 450: Transformers and Transformer Vaults (Including Secondary Ties)
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## Part I. General Provisions
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@@ -0,0 +1,13 @@
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---
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id:
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aliases:
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- nec-520
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tags:
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- authorship/other
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- destiny/uncertain
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- status/incomplete
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- topic/electrical
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- type/media
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title: "Article 520: Theaters, Audience Areas of Motion Picture and Television Studios, Performance Areas, and Similar Locations"
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---
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# Article 520: Theaters, Audience Areas of Motion Picture and Television Studios, Performance Areas, and Similar Locations
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> * Theatrical Switchboards
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> * Stage Switchboards
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Company switches are lighting control devices
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unique to performance venues
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like those subject to **NEC Article 520:
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Theaters, Audience Areas of Motion Picture and Television Studios,
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Performance Areas, and Similar Locations**
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![[company-switch.png|500x625]]
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Company switches are lighting control equipment
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unique to performance venues
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like those subject to [[nfpa-70_520_theaters]]
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> [!cite] NEC Article 520.2
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> **Stage Switchboard.**
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> A permanently installed switchboard, panelboard, or rack
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