IBM SAN50C-R Installation, Service And User Manual page 46

Establishing the System Ground
This section describes how to connect a system ground to the IBM SAN50C-R
switch.
Note:
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:
v You must install the system (NEBS) ground connection with any other rack or
v You must connect both the system (NEBS) ground connection and the power
To connect the ground system, you need the following tools and materials.
v Grounding lug—A two-hole standard barrel lug. Supports up to 6 AWG wire.
v Grounding screws—Two M4 x 8mm (metric) pan-head screws. Supplied as part
v Grounding wire—Not supplied as part of accessory kit. The grounding wire
v No. 1 Phillips screwdriver.
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SAN50C-R Installation, Service, and User Guide
Place a removed component board-side-up on an antistatic surface or in
a static shielding container. If you plan to return the component to the
factory, immediately place it in a static shielding container.
Never attempt to remove the printed circuit board from the metal carrier.
Table 5.
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.
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.
Note: The system (NEBS) ground serves as the primary safety ground for the
IBM SAN50C-R chassis that are equipped with DC-input PEMs. The DC-input
power supplies for these chassis do not have a separate ground.
Supplied as part of accessory kit.
of the accessory kit.
should be sized according to local and national installation requirements.
Depending on the power supply and system, a 12 AWG to 6 AWG copper
conductor is required for U.S. installations. Commercially available 6 AWG wire
is recommended. The length of the grounding wire depends on the proximity of
the switch to proper grounding facilities.
For safety reasons, check the resistance value
of the antistatic strap periodically. The
measurement should be between 1 and 10
megohm (Mohm).