• 本课程为精品课,您可以登录eeworld继续观看:
  • PHASE ARRANGEMENT - 408.3(E) AND (F)​​​​​​​
  • 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

    菜鸟玩ubuntu和PC和板子互ping小总结
    近期使用VM8安装了ubuntu12.10玩玩,途中也遇到了许多问题,安装完成后,系统默认是选择NAT连接方式的,可以直接通过火狐浏览器上网。(不需任何设置,系统自己配置好了)。但是在和PC和板子互ping的时候出现了问题,首先,PC的IP是固定的(公司固定的),因此使用NAT模式的ubuntu系统和PC互ping不能实现。很明显,ifconfig查看ubuntu的ip和PC 的ip是不同网段的。
    zhoouauruheng Linux开发
    用keil编译工程出现Error:C3065E: Type of input file 'ftl' unknown.
    大家好:我用keil在编译一个工程的时候出现了ERROR,Error:C3065E: Type of input file 'ftl' unknown.Error:C3079E: armcc command with no effect.找了一些网上文章说是设置问题,该怎么设置,谢谢拉,大家帮忙
    xiaoyuanhb09 嵌入式系统
    提供PXA310开发系统 (提供CE6.0和WM6.0)
    CPU:Marvell PXA310主频:624MHzAudio Codec:Wolfson WM9713板载LCD:3.5 TFT 高分辨率(320X240)液晶显示器,带触摸屏LCD 接口支持最高分辨率:640X480标准20-Pin JTAG 接口2 个RS232 串口,一个是直连线接口,一个是交叉线接口,使用方便;10M/100M 自适应以太网接口VGA 接口,方便连接电脑显示器外部存储器
    zhaohepi 嵌入式系统
    关于多键触摸IC单线读取问题
    不知触摸ic型号。六个弹簧式按键连接触摸ic,触摸ic只有一个端口连接单片机,当没按时,触摸ic一直高电平给单片机,有按键反应时,输出一段方波。
    徐新 单片机
    来晒一下收到的奖品——加湿器
    [size=4]哈哈,京东物流很给力啊,今天一早一到公司就收到了本来还以为会是挺小的一个呢,拿到手才感觉挺大啊,哈哈做工也很不错[/size][size=4]这个是风量调到最小[/size][size=4]这个是最大[/size][size=4]哈哈,总之,感谢论坛的奖品,以后一定会多多支持论坛的活动滴~[/size]:carnation:
    anqi90 聊聊、笑笑、闹闹
    电路故障分析
    [p=25, null, left][color=#000][font=Tahoma, Helvetica, sans-serif]大家好!遇到一个故障问题,请教各位。[/font][/color][/p][p=25, null, left][color=#000][font=Tahoma, Helvetica, sans-serif]产品是一个零火线的灯光控制设备(使用ZigBee)。硬件电路设
    nicole088 电源技术

    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