• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>IEEE IAS Pulp, Paper and Forest Industries Conference >Transformer Fuse Sizing - The NEC is not the Last Word
【24h】

Transformer Fuse Sizing - The NEC is not the Last Word

机译：变压器保险丝尺寸-NEC不是硬道理

获取原文
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

It is widely accepted that transformer primary side fuses should be appropriately sized. Proper sizing involves consideration of fault and overload conditions that are possible. The basis for such sizing is commonly derived from NEC limits. These NEC imposed limits are the legal limits, but direct application of these maximum values to size transformer primary side fuses is ill-advised. The primary side fuse for medium voltage (MV) applications greater than 1000 volts, as with most MV protective devices, is not intended to provide overload protection. That is achieved by design (considering the intended loading on the transformer). The National Electrical Code recognizes this by permitting the fuse to be sized up to 300 percent of the transformer full load ampere rating. It is generally not a good idea to apply the NEC as an absolute standard for fuse sizing to protect transformers in the absence of the application of other techniques (such as plotting the ANSI/IEEE thermal-mechanical damage characteristic for transformers on a time current curve along with the primary side (MV) fuse time current curve characteristic). These considerations are discussed in the course of this paper. The focus here is on dry type, low voltage (LV) transformers, although the content can be easily extended to liquid filled transformers by using the equations from the appropriate standard.
机译：变压器初级侧熔断器的尺寸应被适当接受。正确确定尺寸时要考虑可能出现的故障和过载情况。此类调整的依据通常来自NEC限制。这些NEC施加的限制是法律限制，但建议不要将这些最大值直接应用于变压器一次侧熔断器的尺寸。与大多数MV保护设备一样，用于中压（MV）应用的1000伏以上的初级侧保险丝也不能提供过载保护。这是通过设计实现的（考虑变压器的预期负载）。美国国家电气法规通过允许将保险丝的尺寸定为变压器满载安培额定值的300％，从而意识到了这一点。在没有应用其他技术的情况下（例如在时间电流曲线上绘制变压器的ANSI / IEEE热机械损坏特性），将NEC用作保险丝尺寸的绝对标准来保护变压器的做法通常不是一个好主意。以及原边（MV）熔断器时间电流曲线特性）。这些注意事项在本文中进行了讨论。这里的重点是干式，低压（LV）变压器，尽管使用适当标准中的公式可以很容易地将内容扩展到充液变压器。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号