NCS Pearson 5000i Installation Manual Download Page 24

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then another code-approved method must be used. (The isolated ground conductor is noted
in the National Electrical Code

{

XE "National Electrical Code"

}{

XE "NEC" \t "

See

National

Electrical Code"

}

, Section 250-74, Exception 4.) Use of an isolated ground rod or grounding to

a water pipe is not acceptable.

An isolated/insulated ground conductor, equal to or larger in size than the heaviest gauge
AC feeder conductor in the circuit, should be bonded to the ground bus in the building main
power panel. Route it with the circuit conductors in the wiring conduit. Pass this ground
through any intermediate panel boards without connection to the panel board grounding
terminal bars. The National Electric Code, cited above, allows for the installation at the
intermediate panel board of an isolated ground bus, constructed from a terminal block kit,
for the interconnection of the isolated ground conductor.

This isolated/insulated ground conductor runs as a single, uninterrupted circuit between the
building main power panel and the 5000

system branch power panel. It forms the

interconnection point for the third-wire

{

XE "Ground:Third-wire" \i

}

grounds of all 5000

system components. Connect all 5000

system component third-wire grounds to this ground;

do not connect any equipment other than 5000

system components to this ground conductor.

This condition is met if all system components are plugged into the

{

XE "Switched

convenience outlet" \t "

See

Convenience outlet"

}

switched convenience outlet

{

"Convenience outlet:switched"

}{

XE "Electrical outlet, convenience" \t "

See

convenience

outlet" \i

}{

XE "Outlet, convenience" \t "

See

Convenience outlet"

}

in the base of the scanner.

1) At some sites, local regulations require that all installed equipment be connected

to a system common ground. In this case, connect all 5000

system components to

the common ground at only one point. Connect third wire grounds of system
components onto a common bus that is connected to the common ground at a
single point.

2) Make sure the equipment third-wire { XE "Ground:Third-wire" \i }ground (green

wire) does not become connected to the conduit at the outlet box or connector. To
avoid an inadvertent connection, use a NEMA 5-20R type isolated-ground
receptacle, such as a
Hubble IG-5362.

Grounding in Multi-Story Buildings{ XE "Grounding:In multistory
building" \i }

When installing the 5000

system in a multi-story building

{

XE "Multistory building,

grounding" \t "

See

Grounding in multistory building"

}

, provide a low noise ground by

connecting the isolated

{

XE "Conductor:Isolated/insulated"

}

ground

{

"Ground:Conductor" \i

}

of the system to the structural steel of the building. Install the

isolated ground system as described above. In addition, bond one end of a heavy gauge wire
or copper braid to the isolated ground bus in the branch circuit panel serving the 5000

system. Weld the other end of this wire or braid to the nearest vertical steel structural
member. Do not substitute a water pipe or an isolated ground rod for the vertical steel
member.

Page 12

5000

Scanner Installation Guide