久久精品这里热有精品,国产综合自拍,免费啪啪视频一区,殴美国产中文字幕视频在线观看,日韩不卡无码精品一区高清视频,欧美a视频在线观看,亚洲国产成人手机在线观看,欧美精品不卡

          National Standard for Terminal Blocks

          National standard


          old standard


          No. Standard No. Standard Name Approval or Release Date Implementation Date [3]


          1 GB/T14048.1 Low-voltage switchgear and control equipment General provisions 2000-10-17 1993-01-04 2001-07-01 1993-07-01


          2 GB14048.2 Low-voltage circuit breakers 2001-11-21 1994-04-12 2002-11-01 1994-12-01 [3]


          3 GB14048.3 Switch, isolator, isolating switch and fuse combination electrical appliances 2002-06-13 1993-09-05 2003-01-01 1994-04-01


          4 GB14048.4 Electromechanical contactors and motor starters 2003-09-10 1993-09-05 2004-05-01 1994-04-01


          5 GB14048.5 Control circuit electrical appliances and switching elements 2001-11-02 1993-09-05 2002-06-01 1994-04-01 [3]


          The above-mentioned five new standards are equivalent to the standards of the same name of IEC60947.1-5. Taking into account the actual environmental conditions in my country, two kinds of humidity resistance requirements and test methods, constant damp heat and alternating damp heat, are added to GB14048.1-2000 Appendix K, and it is required that the product standard should select the corresponding humidity resistance assessment method according to its own characteristics. . [3]


          The main differences between the old and new standards


          The main common differences between the above five new and old national standards are: [3]


          a. The new standard cancels some structural and material performance requirements in the old standard. Such as vibration resistance, impact resistance, impact resistance, aging resistance of elastic parts, low temperature and (high temperature) performance, heat resistance, rust resistance, etc. [3]


          b. The electromagnetic compatibility of the new standard includes immunity (surge immunity, electrical fast transient/burst immunity, radio frequency electromagnetic field radiated immunity and electrostatic discharge immunity) and emissions (radiated and conducted). The old standard only has the requirements of anti-electromagnetic interference (anti-high-frequency conducted interference, anti-high-frequency radiation interference, anti-low-frequency conducted interference and anti-surge over-voltage conducted interference).


          c. The difference between the power frequency dielectric test voltage values of the new and old standard main circuits is as follows. [3]


          The difference of the power frequency dielectric test voltage value of the main circuit [3]


          Rated insulation voltage Ui


          (V) Power frequency dielectric test voltage value


          (RMS) (V) [3]


          Ui≤60 1000


          60<Ui≤300 2000


          300<Ui≤690 (old standard 660) 2500


          690 (old standard 660) <Ui≤800 3000 [3]


          800<Ui≤1000 3500


          1000<Ui≤1500 (only for DC) 3500 (old standard 4200)


          d. The new standard does not specify the number of test samples for type testing, while the old standard stipulates that each test should be at least 2 sets. [3]


          e. Periodic tests in the old standard have been deleted from the new standard.


          f. In the new standard, the life test (mechanical life and electrical life test) is listed as a special test item, and in the old standard, the life test is a type test item.



          g. The transport and storage tests in the old standard are deleted from the new standard. [3]


          Related News

          Related Products

          主站蜘蛛池模板: 久久亚洲AV成人一二三区| 成人小视频在线观看播放| 久久精品国产亚洲av高清3p| 国产一级a爱做片一女多男| 亚州AV成人无码久久精品| 国产日产欧洲无码视频无遮挡 | 久热香蕉av在线爽青青| 免费午夜爽爽爽WWW视频十八禁| 麻花豆传媒剧国产mv网站入口| 成午夜精品一区二区三区| 亚洲中文无码永久免费| 久久狠狠爱亚洲综合影院| 日本一区三区高清视频 | 2021国产成人精品国产| 日韩欧美在线综合网| 帅男chinesegay飞机| 青榴社区国产精品| 国产va免费精品高清在线观看| 国产精品自在拍首页视频8| 大地资源网高清在线观看| 日韩av一区在线播放| 日本熟妇精品一区二区三区| 午夜a福利| 婷婷色一二三区波多野衣| 日韩人妻无码一区二区三区| 日韩高清视频 一区二区| 国产69口爆吞精在线视频喝尿| 久久精品伊人无码二区| 亚洲av永久无码精品网址| 亚洲熟妇无码一区二区三区导航| 蜜桃视频免费高清观看在线播放 | 免费人妻精品一区二区| 国产在线一区二区三区在线观看| 粉嫩小泬无遮挡久久久久久| 琪琪的色原网站| 在线视频一区二区亚洲| av免费一区二区三区不卡| 最新最近中文字幕亚洲| 琪琪女色窝窝777777| 午夜一区二区三区av| 亚洲天堂免费一二三四区|