• Each DC power source must comply with the safety extra-low voltage (SELV) requirements in UL
60950-1, CSA-C22.2 No. 60950-1, EN60950-1, AS/NZS 60950, and IEC60950-1.
• A DC-powered system should be installed in a restricted access area in accordance with the National
Electric Code, ANSI/NFPA 70.
• All components in the area where DC input power is accessible must be properly insulated.
If it is not possible to rely on the identification of the earthed conductor in the DC mains supply, whereby the
equipment is not provided with a two-pole disconnect device, then a two-pole disconnect device is to be
provided external to the equipment.
NEBS Supplemental Unit Bonding and Grounding Guidelines
You must connect the central office ground system or interior equipment grounding system permanently to
one of the two supplemental bonding and grounding connections on the back or side of the chassis to meet
Network Equipment Building System (NEBS) requirements as well as safety compliance requirements. These
grounding points are referred to as the NEBS bonding and grounding points
These bonding and grounding connections satisfy the Telcordia NEBS requirements for supplemental bonding
and grounding connections. If you are not installing the chassis in a NEBS environment, you can choose to
bypass these guidelines and rely on the safety earth ground connections to the AC power modules.
Note
Figure 40: NEBS Bonding and Grounding Points on NCS 4016
NEBS grounding point on front of chassis
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Hardware Installation Guide for the Cisco NCS 4000 Series
56
Installing Power Components
NEBS Supplemental Unit Bonding and Grounding Guidelines
Summary of Contents for NCS 4000 Series
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