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| | | | | 浪涌电压承受能力与线路结构有关,压敏体积没有一定,根据测试最终来定。 |
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| | | | | | | | | | | | | 关系很大,单级PFC的浪涌能力很差,有大电解的会好;EMC有CLC器件的会好,没有的会差。所以这跟你的线路拓扑,配置有关
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| | | | | | | | | | | | | | | 楼主问的是MOV,不是EMC。MOV貌似和EMC没有什么关系。
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| | | | | | | | | | | | | | | | | 当然这里不是讲EMC
但是EMC元件对浪涌有一定抑制作用,对MOV的体积大少有所影响
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| | | | | inrush current要按照客户规则测再选定合适NTC 还有测试仪器很大差别,像6560 6590测出来的值就会有很大差异 |
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| | | | | | | 像dell要求
264V 35°半载 burn in半小时第一根不能超110A第二根35A |
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| | | | | UL1449将SPD(surge protective Device)分成4种类型,分别为:
Type1 – Permanently connectedSPDs intended for installation between the secondary of the service transformerand the line side of the service equipment over current device, as well as
the load side, including watt-hour meter socket enclosures andintended to be installed without
an external over current protective device..
Type 2 – Permanently connected SPDs intended forinstallation on the load side of the service
equipment over current device; including SPDs located at the branchpanel.
Type 3 – Point of utilization SPDs, installed at aminimum conductor length of 10 meters (30
feet) from the electrical service panel to the point ofutilization, for example cord connected,
direct plug-in, receptacle type and SPDs installed at theutilization equipment being protected.
See marking in 64.2. Thedistance (10 meters) is exclusive of conductors provided with or used to attach SPDs.
Type 4 – Component SPDs, including discrete componentsas well as component assemblies.
大致来讲,type1 - type4的用途如下:
Type1 - 用于进户线到总配电板上
Type2 - 用于分配电板上
Type3 - 用于拖线板上,我们可用于开关电源上
Type4 - 用于器件的保护上,比如并联在可控硅上用于保护可控硅
也就是说压敏电阻至少要选择Type3或以上,我们来看厂家的规格书,注意画圈部分:
过浪涌测试,现在一般至少要达到2KV,出口通常要4KV,4KV对应的是2KA电流(8/20us)。这个只有10D及以上才能达到。7D通常只有1.8KA。
MOV的选择归纳如下:
1)有UL认证
2)压敏电压 = 2.2倍的标称交流电压
3)Type3或以上
4)10D或以上
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| | | | | 有人仔细按客户的降额要求算过吗?不要谈靠经验。这个是可以计算的。 |
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| | | | | | | 楼上,你好,请问这个公式如何计算的,能否给我分享一下,我刚刚入门,想了解一下计算的由来公式,这样心里起码有个底的
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