• 本课程为精品课,您可以登录eeworld继续观看:
  • EXTENSION CORD SETS - 240.5(B)(3)
  • 登录
课程介绍
相关标签: 电子系统
Switchboards are designed with busbars for fuses or circuit breakers that are used for protecting and supplying feeders and branch circuits. Panelboards are designed with a permanently installed main circuit breaker or single set of fuses for disconnecting the number of circuit breakers or fuseholders installed to protect and supply feeders or branch circuits.

SUPPORT AND ARRANGEMENT OF BUSBARS AND CONDUCTORS
408.3

Busbars shall be held firmly in place in the enclosure and shall be arranged in such a way to allow adequate space for conductors to be terminated. Busbars shall be sized with enough capacity to handle the normal currents in amps of the electrical system. In addition, they shall carry safely any type of short-circuit or ground-fault condition.

CONDUCTORS AND BUSBARS ON A SWITCHBOARD OR PANELBOARD
408.3(A)

Conductors and busbars on a switchboard, panelboard, or control board shall be so located as to be free from physical damage. Service sections of such boards shall be separated from the other electrical components. These components shall be properly secured in an approved manner. 

Note, conductors entering a certain section shall terminate in such section, except where it is not practical for control, interconnecting conductors, or other conditions of use.

OVERHEATING AND INDUCTIVE HEATING
408.3(B)

The arrangement of busbars and conductors shall be such as to avoid overheating due to inductive effects. The inductive effect of each conductor is neutralized when grouping all conductors together. To accomplish the minimizing of heating effects, the ungrounded (phase) conductors, grounded (neutral) conductors, and equipment grounding conductors, where used, shall be in the same enclosure, raceway, cable, cord, etc. (See Figure 7-1)

显示全部 ↓
推荐视频

    猜您喜欢

    推荐帖子

    遇到一个浏览器的问题,很纠结!!!(求助)
    因为上网查资料经常要开几十个页面,(因为屏幕宽度限制)当开到30+以后,基本上就看不到每个标签页中的内容了。我曾经试过把浏览器窗口拉到两个屏幕宽,或者启动多个浏览器,但是这两种方法在具体使用时都不是很不方便。最好能有多行显示标签页的浏览器(跟vim中的标签显示方式类似就好,切换还方便)。请问各位朋友有遇到过和我类似的问题吗?如何解决的呢??
    henryli2008 聊聊、笑笑、闹闹
    求助高手 做一个锁相环电路
    [i=s] 本帖最后由 dontium 于 2015-1-23 13:29 编辑 [/i]新手求救,一个锁相环电路,中心频率40M,输出DC--3M,不知道如何做,求大侠指点一下:Sweat:[[i] 本帖最后由 yanghuiguang 于 2011-8-3 10:27 编辑 [/i]]
    yanghuiguang 模拟与混合信号
    ST巡回研讨会网友们都收到的是什么板子啊
    [font=微软雅黑][size=4]今天听huaiqiao在群里说收到了F4的板子:sexy:,你们收到的也是F4吗?[/size][/font][font=微软雅黑][size=4][/size][/font][font=微软雅黑][size=4]打算怎么完啦,收到F4的要不要约着一起玩一波哈。[/size][/font]{:1_123:}[table=162][tr][td=162]@Bin
    nmg stm32/stm8
    跪求Windows Mobile 5.0的SDK文档下载!
    我在MSDN的网站上虽然能够看到SDK的帮助文档,但是不知道为什么里面的SAMPLE没有的下载?请问同志们知道那里有完整的Windows Mobile 5.0的SDK下载吗?
    daijun20803 嵌入式系统
    请问大家非接触读卡器 天线匹配参数如何调整?
    请问大家非接触读卡器 天线匹配参数如何调整?有没有简单的查表法?
    nanstone 无线连接
    赚分...
    0
    zkissinger 嵌入式系统

    推荐内容

    可能感兴趣器件

    完成课时学习+分/次

     
    EEWorld订阅号

     
    EEWorld服务号

     
    汽车开发圈

     
    机器人开发圈

    About Us 关于我们 客户服务 联系方式 器件索引 网站地图 最新更新 手机版 版权声明

    站点相关: 汽车电子 智能硬件

    北京市海淀区中关村大街18号B座15层1530室 电话:(010)82350740 邮编:100190

    电子工程世界版权所有 京B2-20211791 京ICP备10001474号-1 电信业务审批[2006]字第258号函 京公网安备 11010802033920号 Copyright © 2005-2025 EEWORLD.com.cn, Inc. All rights reserved