Approved Grounds - Avaya G250 Installation And Upgrade Manual

The customer will need to provide a means of connecting this Supplementary Ground
Conductor to an approved ground according to Article 250 of the National Electrical Code
(NEC).
!
DANGER:
For custumer-installed euipment, failure to install the Supplementary Ground
DANGER:
Connector will void the Product Safety certifications (UL and the CE Mark) on the
product, as well as allow a hazard to be present that could result in death or
severe personal injury.

Approved grounds

An approved ground is the closest acceptable medium for grounding the building entrance
protector, entrance cable shield, or a single-point ground of electronic telephony equipment. If
more than one type of approved ground is available on the premises, the grounds must be
bonded together as required in Section 250-81 of the NEC for the US or per the local electrical
code regulations in the country of installation.
Grounded Building Steel. The metal frame of the building where it is effectively grounded
●
by one of the following grounds: acceptable metallic water pipe, concrete encased ground,
or a ground ring.
Acceptable Water Pipe. A metal underground water pipe, at least 1/2-in. (1.3 cm) in
●
diameter, in direct contact with the earth for at least 10 ft. (3m). The pipe must be
electrically continuous (or made electrically continuous by bonding around insulated joints,
plastic pipe, or plastic water meters) to the point where the protector ground wire connects.
A metallic underground water pipe must be supplemented by the metal frame of the
building, a concrete-encased ground, or a ground ring. If these grounds are not available,
the water pipe ground can be supplemented by one of the following types of grounds:
- Other local metal underground systems or structures, such as tanks and piping systems.
- Rod and pipe electrodes. A 5/8-in. (1.6 cm) solid rod or 3/4-in. (2 cm) conduit or pipe
electrode driven to a minimum depth of 8 ft. (2.4 m).
- Plate electrodes. Must have a minimum of 2 sq. ft. (0.185 sq. m) of metallic surface
exposed to the exterior soil.
Concrete Encased Ground. An electrode encased by at least 2 in. (5.1 cm) of concrete
●
and located within and near the bottom of a concrete foundation or footing in direct contact
with the earth. The electrode must be at least 20 ft. (6.1 m) of one or more steel reinforcing
bars or rods, 1/2-in. (1.3 cm) in diameter, or at least 20 ft. (6.1 m) of bare solid copper, 4
AWG (26 mm
Ground Ring. A buried ground that encircles a building or structure at a depth of at least
●
2.5 ft (0.76 m) below the earth's surface. The ground ring must be at least 20 ft. (6.1 m) of
2 AWG (35 mm
2 ) wire.
2 ), bare copper wire.
Step 3: Attach ground conductors
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