Calix 500 Series, Руководство пользователя

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NEC and Grounding
A very important aspect of any ONT installation is to comply with the National Electric
Code (NEC), as well as all state and local codes. Article 800 of the NEC requires the ONT to
be grounded according to Article 250.56 of the code. To be properly grounded, the ONT
must be directly bonded to the building’s AC utilities earth ground electrode using a #6
AWG copper conductor. The earth electrode can be a metallic cold water pipe or a copper
clad steel rod that has been driven into the ground to a depth of at least 8 feet.
Metallic cold water pipes that run under ground for a distance of at least 10 feet are
considered the best ground electrodes. The NEC requires that if cold water pipes are used
they must be within 5 feet of the outside wall that the ONT is mounted on.
In the event that the ONT is installed more than 20 feet from the building AC utility earth
ground electrode, a suitable secondary ground electrode must be provided. The secondary
ground must be bonded to the building’s primary earth electrode. A bonding jumper of #6
AWG copper must be used between the two electrodes.