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nfpa-70_450_transformers.md

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+---
+id:
+aliases:
+  - nec-450
+tags:
+  - authorship/other
+  - destiny/uncertain
+  - status/incomplete
+  - topic/electrical
+  - type/encyclopedia
+---
+# Article 450 Transformers and Transformer Vaults (Including Secondary Ties)
+
+## Part I. General Provisions
+
+### 450.1 Scope.
+
+This article covers the installation of all transformers.
+
+Exception No. 1:
+Current transformers.
+
+Exception No. 2:
+Dry-type transformers
+that constitute a component part of other apparatus
+and comply with the requirements for such apparatus.
+
+Exception No. 3:
+Transformers that are an integral part
+of an X-ray, high-frequency, or electrostatic-coating apparatus.
+
+Exception No. 4:
+Transformers used with Class 2 and Class 3 circuits
+that comply with Article 725.
+
+Exception No. 5:
+Transformers for sign and outline lighting
+that comply with Article 600.
+
+Exception No. 6:
+Transformers for electric-discharge lighting
+that comply with Article 410.
+
+Exception No. 7:
+Transformers used for power-limited fire alarm circuits
+that comply with Part III of Article 760.
+
+Exception No. 8:
+Transformers used for research, development, or testing,
+where effective arrangements are provided
+to safeguard persons from contacting energized parts.
+
+This article covers the installation of transformers
+dedicated to supplying power to a fire pump installation
+as modified by Article 695.
+
+This article also covers the installation of transformers
+in hazardous (classified) locations
+as modified by Articles 501 through 504.
+
+<!-- TODO: TEXT OMITTED -->