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Electrical systems with voltages significantly lower than mains wiring. Examples include ethernet, telephone, cable tv, and alarm systems.

Low-voltage electrical systems are those with voltages significantly lower than standard mains wiring. In the US at least, these systems don't generally require inspections.

United States

  • Mains wiring: 120V
  • Telephone wiring: 48V DC (~90V AC when ringing)
  • Ethernet: 5V
  • Alarm systems: typically 12V
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