Grounding The Nebs 2000 Frame - Nortel Passport 15000 Hardware Installation And Maintenance

368 Chapter 17 Hardware procedures

Grounding the NEBS 2000 frame

Prerequisites
241-1501-240 5.2S2
Install a cable onto the top front or rear of a NEBS 2000 frame to ground all
equipment in the frame to the site ground window, or onto the mounting
apparatus of a shelf-based Passport 15000 or 20000.
• You must be familiar with "Safety considerations and best practices"
(page 53).
• You need the kit A0682225 which includes a straight 2-hole lug for a
No. 6 AWG (13.3 mm
head screws or green pan-head machine screws. If you use a thicker
grounding cable, provide your own lug and fasteners.
• When measuring the length of the frame grounding cable, ensure that
you accommodate having the cable go through the frame bracket in the
procedure "Installing a top frame bracket onto a NEBS 2000 frame"
(page 568). It is easier to fasten the thread-forming screws of the ground
cable before the bracket is installed. However, you should install the
bracket before powering up any equipment in the frame.
• For top or bottom grounding to a common bonding network (CBN) or an
isolated bonding network (IBN), meet the following criteria, especially
when using a common power plant to feed both IBN and co-located small
CBN equipment.
— Locate all IBN equipment within one floor of the power plant.
— Use only one single point ground (SPG) for all IBN equipment fed
from the power plant. That is, use a non-current-carrying section of
the insulated battery return (BR) bar of the power plant.
— Insulate the BR bar of the power plant from the Passport 15000 or
20000 and bond to the frame ground bar (FGB) for CBN or to the
SPG for IBN.
— Bond the framework of the power plant to the FGB overhead or
under the floor.
— Grounding conductors are not designed to carry current under
normal operating conditions.
2
) cable and 2 thread-forming10-mm (3/8-in.) hex-