4.41 翻译实例

System Features

The systems used to build a telecommunications networks for power grid applications are often installed in extreme climatic conditions, such as in deserts, jungles or arctic environments.The equipment is frequently installed in unattended sites and must meet stringent requirements for long maintenance intervals.All of these factors call for a very varied palette of features ranging from equipment protection to flameresistant and shot-resistant optical fibre cable, to efficient network management systems.

When mains power supply is not available, or is unreliable, alternative power supplies must be installed, such as diesel generators, solar cells, wind generators and backup batteries.

Due to the increasing sensitivity of modern electronic equipment, good sheltering is required to protect the equipment against power supply surges, lightning, extreme climatic conditions and other disturbing factors.When containerized shelters are used as the installation premises, the entire system can be made modular, making it easy to change the network's design.Inside the container, components are protected in high-quality cabinets that are often electronically shielder.These containerized stations are delivered by helicopter or truck, and are usually installed in only a few days.

Telecommunications equipment should also comply with EMI（electromagnetic interference）and EMC（electromagnetic compatibility）standards, meaning that the telecom system must not disturb, or be disturbed by, other electronic, electric or radio systems in the vicinity, which can affect the operation of the power distribution network or its control systems.This is where a thorough installation design, shielded cabinets and/or shelters, good grounding, lightning arresters and overvoltage transient protectors play a crucial role.

If a telecommunications network is compared to the nervous system of a human being, the network management system is the brain.The network management system is essential for the operation and maintenance of the network, and to realize availablility and safety goals.

电讯网络系统特点

为使用电网而建的电讯网络系统往往安装在沙漠、丛林或极性地带等气候恶劣的环境中，设施无人值守，因此必须符合维修时间间隔长的严格要求。这些因素要求具备各种性能，包括设施保护、防火、抗震的光缆和有效的网络管理系统。

在无电或者电源不稳定的情况下，必须安装备用电源，如：柴油发电机、太阳能电池、风力发电机或备用电池。

由于现代电子设备的灵敏度越来越高，因此需要良好的屏蔽，以保护设备免受电涌、闪电、极端气候条件和其他干扰因素的破坏。使用集装箱式的屏蔽室作为安装机房，可使整个系统模块化，便于修改网络设计。在集装箱室内组件可以在优质电子屏蔽机柜中得到保护。这些集装箱式的网站是由直升机或卡车运送的，通常几天之内就可以安装起来。

通讯设备也必须执行电磁干扰和电磁相容标准，即：电讯系统与附近的其他电子、电力或无线电系统不能相互干扰，以免影响电力分配网及其控制系统的运作。这正是全面的安装设计、屏蔽机柜或机房、良好的地线、避雷器和瞬变超压保护装置发挥关键作用之处。

如果把通讯网络比作人的神经系统，那么网络管理系统就是头脑。网络管理系统对于网络的运作和维修，对于其可用性和安全目标的实现都是及其重要的。