Aug 29, 2011

Telephone Network Interface Device (NID)

The telephone network interface device typically refers to the junction box mounted by your telephone service provider on a wall just outside your home. Here are some basic information about your telephone network interface device:
  • It is the point where the telephone company terminates their responsibility.
  • You are responsible for installing the wires starting from the NID to each telephone jack inside your home.
  • To locate the box, simply trace the line that runs from the utility pole into your home.
  • The NID is made of hard plastic and is weatherproof.
  • Unplugging the short cable inside the NID from its jack will disconnect power and signals from the telephone company.
  • Plugging a working telephone into a jack inside the NID will allow you to know if there is power and signals running from the telephone company into your household wiring.
  • The NID is maintained by the telephone company.
  • The red and the green wires running from the telephone jack inside your home connects to similar colored terminals inside the jack.
          Reference: Public Service Commission of Wisconsin: Testing, Repairing and Installing Home telephone Wiring - Locating the Demarcation Point


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