亚洲男女内射在线播放,狂野黑人性猛交xxxxxx,我要看曰批全过程免费,91人妻人人澡人人爽人人精品,欧美最大胆的西西人体44,国自产拍偷拍福利精品免费一,欧美国产日本高清不卡,久久国产精品_国产精品,99热国产免费,99久RE热视频这里只有精品6

  • <ul id="6q2ga"></ul>
    AC source power & DC source power manufacturing factory

    DC electricity is not dead?

    Does DC power kill people? Depending on the size of the current passing through the human body, it has nothing to do with alternating current or direct current.
    We usually use three-phase four-wire AC power supply, three-phase namely three fire lines, the phase difference of three-phase AC is 120 degrees, the other line is called neutral line. Three-phase electricity is difficult to balance, so the neutral line is necessary for the client.

    There are several kinds of electric shock: contacting two fire wires; a fire line and a neutral line, which can form a circuit, with current flowing through the human body; when a person contacts only one fire line, if a person is connected with the earth, it also constitutes a circuit, with current flowing through the human body; and then it is striding electric shock, when the high voltage ground is grounded, the earth has resistance, forming an area with voltage outside the ground point, and when a person enters, two feet. There are voltage and current between them.

    But direct current is different. It must supply power with two lines, so it must contact two lines at the same time to form a circuit. The chance of electric shock is greatly reduced, and there are fewer places for HVDC power supply, so there will be fewer electric shock accidents. This is not that DC power is not dead!
    Recommend Products
    Online service
    Service Hotline
    86-769-89616802
    86-13602353727

    ADMIRE POWER
    亚洲综合一区国产精品| 国产在线精品一区二区| 日本一道高清不卡免费| 色妞色综合久久夜夜| 国产成人综合亚洲精品| 亚洲AV无码区一区啪啪浪潮| 大尺度无遮挡激烈床震网站| 欧美人妻日韩精品| 中文字幕av一区乱码| 乱码一卡2卡3卡4卡精品| 女人脱了裤衩让男人桶| 视频一区中文字幕| 免费无码av一区二区| 亚洲精品午夜久久久伊人| 中文字幕亚洲无线码在线一区 | 免费观看女人高潮视频网站| 日本欧美高清全视频| 99国产成人精品无码青春| 精品人妻大屁股白浆无码| 中文成人无字幕乱码精品区| 欧美精品免费观看二区| 最新女同电影| 中文字幕av无码一区二区三区电影 | 国产精品水嫩水嫩| 婷婷俺也去俺也去官网| 全免费A级毛片免费看| 国产亚洲日韩一区二区三区| 国产69久久精品成人看| 日本一区二区三区免费播放| 日本一道高清不卡免费| 国产精品国产三级国产a| 久久久久无码精品国产不卡| 福利视频一区二区| 精品一区亚洲| 国产成人综合精品一区| 亚洲欧美一区二区三区另类| 2020国产精品自拍| 欧美浓毛大bbwbbw| 激情航班h版在线观看| 特黄做受又硬又粗又大视频小说| 国产欧美日韩高清专区手机版|