Establishing The System Ground; Required Tools And Equipment - Cisco AJ732A - MDS 9134 Fabric Switch Installation Manual

System Grounding
S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m .
For safety reasons, check the resistance value of the antistatic strap periodically. The measurement
Caution
should be between 1 and 10 megohm (Mohm).

Establishing the System Ground

This section describes how to connect a system ground to the MDS 9500 series switches.
Note This system ground is also referred to as the network equipment building system (NEBS) ground.
You must use the system (NEBS) ground on both AC- and DC-powered systems if you are installing this
equipment in a U.S. or European Central Office.
The system (NEBS) ground provides additional grounding for EMI shielding requirements and
grounding for the low-voltage supplies (DC-DC converters) on the modules and is intended to satisfy the
Telcordia Technologies NEBS requirements for supplemental bonding and grounding connections. You
must observe the following system grounding guidelines for your chassis:
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Note The system (NEBS) ground serves as the primary safety ground for the MDS 9500 series chassis that are
equipped with DC-input PEMs. The DC-input power supplies for these chassis do not have a separate
ground.

Required Tools and Equipment

To connect the ground system, you need the following tools and materials:
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Cisco MDS 9500 Series Hardware Installation Guide
2-22
Never attempt to remove the printed circuit board from the metal carrier.
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You must install the system (NEBS) ground connection with any other rack or system power ground
connections that you make. The system ground connection is required if this equipment is installed
in a U.S. or European Central Office.
You must connect both the system (NEBS) ground connection and the power supply ground
connection to an earth ground. The system (NEBS) ground connection is required if this equipment
is installed in a U.S. or European Central Office.
For MDS 9500 series chassis that are equipped with DC-input power supplies, you must install the
system (NEBS) ground before you attach the source DC power cables to the DC PEM. If the chassis
is powered up, you must power down the chassis before attaching the system (NEBS) ground. If you
are installing the system (NEBS) ground on models of the MDS 9500 series chassis that are
equipped with either AC-input or DC-input power supplies, you do not need to power down the
chassis.
Grounding lug—A two-hole standard barrel lug. Supports up to 6 AWG wire. Supplied as part of
accessory kit.
Grounding screws—Two M4 x 8mm (metric) pan-head screws. Supplied as part of the accessory kit.
Chapter 2 Installing the Cisco MDS 9500 Series
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