Examining Installation Site

51

Cleanness Requirements Dust is a hazard to the operating safety of the switch. The indoor dust accumulated on the chassis can cause electrostatic absorption, which may result in the poor contact of the connector or metal contact point. This happens more frequently when indoor relative humidity is low, which will not only shorten the service life of the switch, but also cause communication failure.

The required specifications on dust content and particle diameter in an equipment room are shown in the following table.

Table 68 Limitation on dust content in equipment room

Mechanical active material

Unit

Content

 

 

 

Dust particle

particles/m3

‚≤3 x 104

(No visible dust on desk in three days)

Note: Dust particle diameter ‚≥ 5µm

Besides the dust specifications, the equipment room of the switch should also meet the rigorous requirements for the content of salt, acid and sulfide in the air. These harmful gases could accelerate the metal erosion and the aging process of some parts. Incursion of harmful gases, such as SO2, H2S, NO2, NH3, and Cl2, should be prevented. The specific limitation values of these harmful gases are given in the following table.

Table 69 Harmful gas limits in an equipment room

Gas

Average (mg/m3)

Max. (mg/m3)

 

 

 

SO2

0.3

1.0

H2S

0.1

0.5

NO2

0.004

0.15

NH3

1.0

3

Cl2

0.1

0.3

 

 

 

Anti-StaticAny possible interference sources, no matter outside or inside the system, affect Requirements the switch in use in a way of capacitive coupling, inductive coupling,

electromagnetic radiation, common impedance (including the grounding system) coupling or conducting line (power line, signaling line and transmission line etc.). To prevent the interference, you should:

■Take effective measures against electrical net interference for power supply system.

■Separate the working ground of the switch from the grounding device of the power supply equipment or lightning-protection grounding device as far as possible.

■Keep the switch far away from the radio launcher, radar launcher, and high-frequency devices working in the high current.

■Adopt electromagnetic shielding if necessary.

Grounding A good grounding system is not only the basis essential to the stable and reliable Requirements switch operation, but also an important guarantee of lightning protection,

anti-interference and ESD-prevention. The user must provide good grounding system for the switch.

Page 50 Page 52
Page 51
Image 51
3Com 8807, 8814, 8810 manual Limitation on dust content in equipment room, Harmful gas limits in an equipment room
Page 50 Page 52

8810, 8814, 8807 specifications

The 3Com 8814, 8810, and 8807 are renowned products from the networking giant 3Com, which played a significant role in the evolution of networking technology in the early 1990s. These devices were instrumental during a time when organizations were transitioning from traditional communication systems to more sophisticated networking solutions.

The 3Com 8814 is a multi-port networking hub designed for small to medium-sized businesses. One of its main features includes a 10Base-T Ethernet capability, allowing for fast and reliable connectivity among various devices within a local area network (LAN). The 8814 supports up to 14 connections, providing scalability for growing businesses. The hub’s ease of use is notable; it features a plug-and-play design, which aids in quick setup without requiring extensive configuration. This plug-and-play functionality, alongside its robust physical and electrical performance, made the 8814 an appealing choice for organizations looking to enhance their networking infrastructure without significant investment.

Moving on to the 3Com 8810, this device is labeled as an intelligent network switch and ushered in advancements in network management and performance. A critical element of the 8810 is its ability to support both 10/100Base-T Ethernet connections, effectively allowing mixed-speed environments. Its built-in management features, enabled by 3Com's networking technologies, offered users the ability to monitor traffic flow, manage bandwidth allocation, and configure network settings through a user-friendly interface. This switch also incorporated advanced features like VLAN support, increasing security and segmentation within networks, which proved invaluable for sophisticated networking environments.

Lastly, the 3Com 8807 represents a more versatile and high-performance switch option suited for larger networks. This model features a stackable design that allows for a broader range of scalability and redundancy. It supports both fast Ethernet and Gigabit Ethernet, ensuring that organizations can expand their network speeds as needed. The 8807 includes features for enhanced fault tolerance and link aggregation, which bolsters reliability and performance under heavy traffic loads. Its integration with 3Com's Network Management Software provided administrators with unprecedented control over their networks, empowering them to optimize performance and troubleshoot issues effectively.

Overall, the 3Com 8814, 8810, and 8807 exemplified the company's commitment to innovation in networking technology, providing businesses with the tools necessary to develop efficient, scalable, and reliable network infrastructures. Each of these devices played a crucial role in shaping the landscape of networking, emphasizing ease of use, management capabilities, and performance.
Top Page Image Contents