Ruijie RG-S6250-48XS8CQ Series Switches Hardware Installation and Reference Guide
Preparation before Installation
- 11 -
Lightning Grounding
The lightning protection system of the facility is an independent 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, not for the device.
For lightning protection, refer to 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 1Ω. There is one grounding connector at the right bottom of the chassis of RG-S6250-48XS8CQ series
switches. The grounding connector is pasted with conspicuous warning labels.
Figure 2-1 EMC grounding
2.2.6 EMI Consideration
Various interference sources, from either outside or inside the device 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 either a part of the interfered system or a
completely electrically isolated unit. Conducted interference results from the electromagnetic wire or signal cable
connection between the source and the sensor. Interference along the cable the interference is transmitted from one
unit to another. Conducted interference often affects the power supply of the device, but can be controlled by a filter.
Radiated interference may affect any signal path in the device, and is difficult to shield.
Effective measures should be taken for the power system to prevent electric grid interference.
The working ground of the routers should be properly separated and kept as far as possible from the grounding
device of the power device or the anti-lightning grounding device.
Keep the device away from high-power radio transmitter, radar transmitting station, and high-frequency
large-current device.
Measures must be taken to isolate static electricity.
