Cisco Systems MGX 8230 manual Connection Description

Chapter 3 Site Preparation

Power and Grounding

Figure 3-3 Mixed Grounding System
							Non-isolated equipment
	– 48V-A			– 48V-A	T	– 48V-A	logic power
		Z1		– 48V-A RTN
				Safety Ground
–	+		Z2	– 48V-B	T
						– 48V-B
Battery A			Z1	– 48V-B RTN
							1
				Safety Ground
			Z2				1
	B
				Z3
		Z2		3				Z5
			Z1
							Isolated equipment
	– 48V-B			– 48V-A	T	– 48V-A	logic power
				– 48V-A RTN
				Safety Ground
–	+			– 48V-B	T
						– 48V-B
Battery B			Z1	– 48V-B RTN
							2
				Safety Ground
			Z2				2	28311
	B
				Z4
				4

Table 3-1 Ground Point Descriptions for Mixed Grounding

Connection	Description
Z1	–48 VDC return.
Z2	Protective earth or safety ground (green/yellow).
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 the building’s ground system: a potential can exist between
	these points within the ground system.
T	Common-mode EMI filters.

Cisco MGX 8230 Edge Concentrator Installation and Configuration

Release 1.1.31, Part Number 78-11215-03 Rev. B0, May 2001 3-19