User manual 3COM S5500-28C-EI

[. . . ] H3C S5500-EI Series Ethernet Switches Installation Manual Hangzhou H3C Technologies Co. , Ltd. http://www. h3c. com Manual Version: 20071215-C-1. 01 Copyright © 2007, Hangzhou H3C Technologies Co. , Ltd. and its licensors All Rights Reserved No part of this manual may be reproduced or transmitted in any form or by any means without prior written consent of Hangzhou H3C Technologies Co. , Ltd. Trademarks H3C, , Aolynk, , H3Care, , TOP G, , IRF, NetPilot, Neocean, NeoVTL, SecPro, SecPoint, SecEngine, SecPath, Comware, Secware, Storware, NQA, VVG, V2G, VnG, PSPT, XGbus, N-Bus, TiGem, InnoVision and HUASAN are trademarks of Hangzhou H3C Technologies Co. , Ltd. All other trademarks that may be mentioned in this manual are the property of their respective owners. Notice The information in this document is subject to change without notice. [. . . ] Connect the yellow-green protection grounding cable before power-on. Make sure that the operating voltage is in the range labeled on the switch. Do not open the chassis to avoid electrical shocks when the switch is operating or just when the switch is powered off. When replacing interface cards, wear ESD-preventive gloves to avoid damaging the cards. 2. 2 Installation Site The S5500-EI series must be used indoors. You can mount the switch in a rack or on a workbench, but make sure: Adequate clearance is reserved at the air inlet/exhaust vents for ventilation. The rack or workbench has a good ventilation system. The rack is sturdy enough to support the device and its accessories. To ensure normal operation and long service life of your switch, install it in an environment that meets the requirements described in the following subsections. 2. 2. 1 Temperature/Humidity You must maintain a proper temperature and humidity in the equipment room. Long-term high humidity may lead to bad insulation, electricity leakage, mechanical property changes, and metal corrosion. However, if the relative humidity is too low, captive screws may become loose as the result of contraction of insulation washers and static electricity may be produced in a dry environment to jeopardize the circuits on the device. A high temperature is the most undesirable condition, because it 2-1 Installation Manual H3C S5500-EI Series Ethernet Switches Chapter 2 Installation Preparations accelerates the aging of insulation materials and thus significantly lowers reliability and service life of the switch. For the temperature and humidity requirements of different models, refer to section 1. 8 "System Specifications of the S5500-EI Series" on page . 2. 2. 2 Cleanness Dust is a hazard to the operating safety of your device. The dust accumulated on the chassis can be adsorbed by static electricity and result in poor contact of metal connectors or metal contact points. Especially when the indoor relative humidity is low, electrostatic adsorption is more likely to happen. This can not only shorten the service life of your device but also cause communications failures. The following table lists the dust concentration limit. Table 2-1 Dust concentration limit in the equipment room Substance Dust 4 Concentration limit (particles//m³) 3 x 10 (no visible dust on the tabletop over three days) Note: The dust diameter is greater than or equal to 5 m. Besides dust, there are rigorous limits on the content of harmful substances in the air that can accelerate the corrosion and aging of metals, such as chloride, acid, and sulfide in the equipment room. The equipment room must be protected against ingression of harmful gases such as SO2, H2S, NH3, and Cl2. For specific requirements, see the following table. Table 2-2 Harmful gas limits in the equipment room Gas SO2 H2S NH3 Cl2 Maximum concentration (mg/m3) 0. 2 0. 006 0. 05 0. 01 2. 2. 3 Electromagnetic Susceptibility The operation of your switch can be affected by external interferences, such as conducted emission by capacitance coupling, inductance coupling, electromagnetic wave radiation, and common impedance (including the grounding system) coupling, and leads (power cables, signaling cables and output wires). To eliminate the interferences, pay attention to the following: 2-2 Installation Manual H3C S5500-EI Series Ethernet Switches Chapter 2 Installation Preparations As the AC power system is a TN system, use a single-phase three-wire power socket with a protection earth (PE) to effectively filter interference from the power grid. Keep the device far away from radio transmitting stations, radar stations, and high-frequency devices. [. . . ] You should correctly locate the problem, whether it is caused because the ground wire of the arrester is not well grounded or because the live and zero wires are connected in reverse direction. You may check that in the following way. When the red LED is on, use a multimeter to examine polarity at the power socket of the arrester. If it is same to that of the power socket in the equipment room, it means that arrester is not well grounded. [. . . ]