低压电气选择原则（Low voltage electrical selection principle）.doc

下载文档 降价啦

3
0
约2.86万字
约 26页
2017-07-15 发布于河南
举报
版权申诉
保障服务

低压电气选择原则（Low voltage electrical selection principle）.doc

1、本文档共26页，可阅读全部内容。
2、有哪些信誉好的足球投注网站（book118）网站文档一经付费（服务费），不意味着购买了该文档的版权，仅供个人/单位学习、研究之用，不得用于商业用途，未经授权，严禁复制、发行、汇编、翻译或者网络传播等，侵权必究。
3、本站所有内容均由合作方或网友上传，本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺！文档内容仅供研究参考，付费前请自行鉴别。如您付费，意味着您自己接受本站规则且自行承担风险，本站不退款、不进行额外附加服务；查看《如何避免下载的几个坑》。如果您已付费下载过本站文档，您可以点击这里二次下载。
4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等，请点击“版权申诉”（推荐），也可以打举报电话：400-050-0827(电话支持时间：9:00-18:30)。

低压电气选择原则（Low voltage electrical selection principle）

低压电气选择原则（Low voltage electrical selection principle） There is no man, but there is one. Books and arts, arts and crafts. I am born to be useful, and thousands of gold to return. It was three thousand feet under the air, and the Milky Way had nine days. 1. Selection of circuit breakers 1. Selection of general low-voltage circuit breakers (1) the rated voltage of the low voltage circuit breaker is not less than the rated voltage of the line. (2) the rated current of the low voltage circuit breaker is not less than the calculation load current of the line. (3) the limiting capacity of the low-voltage circuit breaker is not less than the largest short-circuit current in the line. (4) the single phase of the line at the end of the line has the instantaneous (or short delay) of the short circuit current to the ground circuit breaker, and the fixed current is equal to 1.25 (5) the rated current of the tripper is not less than the calculation current of the line. The rated voltage of the undervoltage trip is equal to the rated voltage of the line. 2. Selection of low voltage circuit breakers for power distribution (1) long delay action current setting is equal to 0. 8 ~ 1 times wire is allowed to carry traffic. (2) the return time of the 3-time long delay action current setting value is not less than the starting time of the maximum starting current in the line. (3) the fixed value of the short delay action current is not less than 1.1 (Ijx + 1.35 KIdem). K is the starting current of the motor; Idem is the maximum rated current for the motor. (4) the short time delay time is checked by the thermal stability of the protected object. (5) no short time delay, the instantaneous current setting value is not less than 1.1 (Ijx + K1KIdem). Among them, K1 is the impact coefficient of starting current of the motor, which can be obtained from 1.7 ~ 2. (6) when there is a short time delay, the instantaneous current setting value is not less than 1.1 times lower than the lower switch i