31 lines
738 B
Markdown
31 lines
738 B
Markdown
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---
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title: Relays
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tags: [electronics]
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created: Monday, September 09, 2024
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---
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# Relays
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A relay is an electrically operated switch.
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It uses an electromagnet to mechancially operate a switch.
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## Core components
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- electromagnet
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- a coil of wire around an iron core
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- armature
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- a movable magnetic strip
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- contacts
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- electrical connections that can be open or closed
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- spring
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- returns the armature to its resting position when not energised
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## Operation
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Current flows through the electromagnet which creates a magnetic field. This
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field attracts the armature which then moves to open or close the contacts. When
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the current stops, this returns the armature to its original position.
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