Ruijie Networks RG-N18010, Hardware Installation And Reference Manual

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The RG-N18000 provides N+M redundancy of power supply. You are recommended to use multiple power
supplies for the equipment to ensure its continuous and stable operation by avoiding the impact of
unexpected power failures on the equipment.
When the dual power supply is applied, the type of the power supply should be identical.
System Grounding Requirements
A good grounding system is the basis for the stable and reliable operation of the RG-N18000. It is the key to prevent
lightning stroke and resist interference. Please carefully check the grounding conditions on the installation site according
to the grounding requirements, and perform grounding properly as needed.
Safety Grounding
The equipment using AC power supply must be grounded by using the yellow/green safety grounding cable. Otherwise,
when the insulating resistance decreases the power supply and the enclosure in the equipment, electric shock may occur.
The building installation shall provide a means for connection to protective earth, and the equipment is to be
connected to that means.
Lightning Grounding
The lightning protection system of the facility is a separate system that consists of the lightning rod, down lead conductor
and the connector to the grounding system, which usually shares the power reference ground and yellow/green safety
cable ground. The lightning discharge ground is for the facility only, irrelevant to the equipment.
For lightning protection, see Appendix C.
EMC Grounding
The ground required for EMC design includes shielding ground, filter ground, noise and interference suppression, and
level reference. All the above constitute the comprehensive grounding requirements. The grounding resistance should be
less than 1
Ω . One grounding point is reserved at the left back of the chassis. The grounding point is pasted with a
conspicuous warning label.
EMI Consideration
Various interference sources, from either outside or inside the equipment or application system, affect the system in the
conductive ways such as capacitive coupling, inductive coupling, and electromagnetic radiation. There are two types of
electromagnetic interferences: radiated interference and conducted interference, depending on the type of the
propagation path. When the energy, often RF energy, from a component arrives at a sensitive component via the space,
the energy is known as radiated interference. The interference source can be both a part of the interfered system and a
completely electrically isolated unit. Conducted interference results from the electromagnetic wire or signal cable
connection between the source and the sensitive component, along the cable the interference conducts from one unit to
another. Conducted interference often affects the power supply of the equipment, but can be controlled by a filter.
Radiated interference may affect any signal path in the equipment, and is difficult to shield.

Effective measures should be taken for the power system to prevent the interference from the electric grid.
 The working ground of the routers should be properly separated and kept as far as possible from the grounding
device of the power equipment or the anti-lightning grounding device.
 Keep the equipment away from high-power radio transmitter, radar transmitting station, and high-frequency
large-current device.
 Measures must be taken to isolate static electricity.