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Cisco MGX 8230 Edge Concentrator Installation and Configuration
Release 1.1.31, Part Number 78-11215-03 Rev. B0, May 2001
Chapter3 Site Preparation Power and Grounding
Figure3-3 Mixed Grounding System
Table3-1 Ground Point Descriptions for Mixed Grounding
Connection DescriptionZ1 –48 VDC return.Z2 Protective earth or sa fety ground (green/ ye llow).Z3 Equipment ground for non isolated equipment.Z4 Equipment ground for isolated equipment.Z5 Equalizing frame ground. This ground creates low-impedance equalization between frames.B Battery ground.1, 2, 3, 4 Connection points to t he building’s ground system: a potential can exist be tw een these points within the ground system.T Common-mode EMI filters.
Battery A
Non-isolated equipment
–48V-A
T
–48V-A –48V-A logic power
+–
–48V-B
1
1
B
2
B
T
T
Safety Ground
Safety Ground
Safety Ground
–48V-A RTN
–48V-A
–48V-A RTN
–48V-B
–48V-B RTN
–48V-B
–48V-B RTN
Safety Ground
Battery B
–48V-B
+–
Isolated equipment
–48V-A logic power
–48V-B
2
4
T
Z1
Z1
Z1
Z1
Z2
Z2
Z2
Z2
Z3
3
Z4
Z5
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