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关于整机接地电阻、绝缘电阻、抗电强度、泄漏电流的问题。

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发表于 2007-12-23 15:36:20 | 显示全部楼层
抗电强度与接地地阻是必须要测试的,这是一个基本要求,此外,有时还要测试绝缘电阻,当然,这要根据不同的要求来.尤其是I类工具.
抗电强度与泄漏电流之间没有什么关系吧?
抗电强度根据防护等级来确定是属于什么绝缘,而泄漏电流是与材料本身有关系的.
发表于 2007-12-26 15:39:14 | 显示全部楼层
1、耐电压检测:对被测电器的外壳或人体易触及的部位,与电源进线端子之间施加一个几千伏高压(交流或直流),检测在这种高电压下有多大的漏电流,漏电流超过一定值时就可能对人身构成伤害。
2、泄漏电流检测:分为动态泄漏和静态泄漏。
(1)静态泄漏:在被测电器的外壳和人体易触及的部位,分别与电源火线、零线端子之间施加额定工作电压的1.06倍电压,检测最大漏电流,此时被测电器不工作。施加的1.06倍电压应通过隔离变压器提供。
(2)动态泄漏:对被测电器供电运行的同时,进行与静态泄漏相同的检测(也称热态泄漏)。
3、绝缘电阻检测:对被测电器的外壳或人体易触及的部位,与电源进线端子之间施加直流电压(一般为1000V、500V或250V),检测在这种电压下的漏电流,折算成绝缘电阻。
4、接地电阻测试:对被测电器外壳与接地端子之间施加恒定的大电流(一般为10A或25A),检测在这种电流下的导通电阻。电阻过大起不到接地保护作用
发表于 2008-3-5 15:15:07 | 显示全部楼层
对于电器的测试,泄漏电流是指在没有故障施加电压的情况下,电气中带相互绝缘的金属零件之间,或带电零件与接地零件之间,通过其周围介质或绝缘表面所形成的电流称为泄漏电流。若考核的是一个电路或一个系统的绝缘性能,则这个电流除了包括所有通过绝缘物质而流入大地(或电路外可导电部分)的电流外,还应包括通过电路或系统中的电容性器件(分布电容可视为电容性器件)而流入大地的电流。较长布线会形成较大的分布容量,增大泄漏电流,这一点在不接地的系统中应特别引起注意。
测量泄漏电流的原理测量与绝缘电阻基本相同,测量绝缘电阻实际上也是一种泄漏电流,只不过是以电阻形式表示出来的。不过正规测量泄漏电流施加的是交流电压,因而,在泄漏电流的成分中包含了容性分量的电流。
接地连续性测试(GC)主要是检测产品的接地端与任何金属表面(通常是指机壳)之间是否导通。典型的接地连续性测试是用万用电表或100毫安的直流电源来完成,如果阻抗是低于1欧姆,那么可以被认为接地是良好。这种接地测试的方式是符合大部份安规标准对产品测试的需求。
相较于接地连续性测试,接地阻抗测试提供一个较高的交流电流给接地端,这个测试是仿真一个频率为60Hz,25安培或更高的故障电流给产品接地端和裸露金属之间,接地阻抗测试是检测接地连结是否可靠、是否具有承受高电流的能力。大部份的标准要求从产品的接地端(保护接地)到导体表面的阻抗不能超过0.1欧姆。
发表于 2008-4-21 23:12:14 | 显示全部楼层
要看你是什么产品啊
发表于 2008-5-8 14:16:34 | 显示全部楼层
例行测试(routine test) 要做什么,而不是类型测试(type test)要做什么.
发表于 2008-5-11 15:58:13 | 显示全部楼层
21楼讲的比较专业,其实现在绝大多数工厂是只做耐压测试HI-POT TEST和接地电阻测试的,有些会做下泄露电流的测试。至于绝缘电阻的测试,现在很少有工厂做这个测试了。
第三方验货公司一般只做耐压和接地电阻的测试。
发表于 2008-5-11 23:25:55 | 显示全部楼层
直接找机构问问例行测试项目就好了;
机构会给你标准答案的;
毕竟场检是否pass由他们说了算


这个最为关键,不过如果你们找不严格的认证机构另外论
发表于 2008-5-12 06:01:12 | 显示全部楼层
IEC61010-1 关于 routing tests 的规定:

从以下的文字可看出,只有K1(接地测试), K2 和K3(耐压测试)是必须的。

有熟悉60950的专家请讲一下差别。

ANNEX K - ROUTINE TESTS (NORMATIVE) «A2
The manufacturer shall perform the tests of K.1 to K.3 on 100% of equipment produced which has both HAZARDOUS LIVE parts and ACCESSIBLE conductive parts. «A2
The ROUTINE TEST is required between supply mains connected together, and ACCESSIBLE conductive parts likely to become energized, including the protective grounding conductor. «NA
Unless it can be clearly shown that the result of tests cannot be invalidated by subsequent manufacturing stages, tests shall be made with equipment fully assembled. «A2
The equipment shall not be unwired, modified or disassembled for the test, but snap-on covers and friction- fit knobs can be removed if they would interfere with the tests. The equipment shall not be energized
during the tests, but the mains switch shall be in the on-position. «A2
Wrapping the equipment in foil is not required, nor is humidity preconditioning necessary. «A2

K.1 Protective earth «A2
A continuity test is made between the earth pin of the appliance inlet or the mains plug of plug-connected
equipment, or the PROTECTIVE CONDUCTOR TERMINAL of PERMANENTLY CONNECTED EQUIPMENT. on
the one side, and all ACCESSIBLE conductive parts which are required by 6.5.1 to be connected to the
PROTECTIVE CONDUCTOR TERMINAL on the other side. «A2

K.2 Mains circuits «A2
A test voltage as specified in annex D for BASIC INSULATION is applied between the mains TERMINALS
connected together on the one side, and all ACCESSIBLE conductive parts connected together on the other.
For this test, the contacts of any output connectors are considered as ACCESSIBLE conductive parts if, in
NORMAL USE, they could become connected to an ACCESSIBLE conductive part outside of the equipment.
«A2
The test voltage is raised to its specified value within 2 s and maintained for at least 2 s. «A2
No breakdown or repeated flashover shall occur. Corona effects and similar phenomena are disregarded.
«A2

K.3 Other circuits «A2
A test voltage is applied between the TERMINALS of floating input circuits, which can be hazardous live in
NORMAL USE, connected together on the one side, and ACCESSIBLE conductive parts connected together
on the other. «A2
A test voltage is also applied between the TERMINALS of floating output circuits, which can be
HAZARDOUS LIVE in NORMAL USE connected together on the one side, and ACCESSIBLE conductive parts
connected on the other. «A2
The value of the applied voltage in each case is 1,5 times the working voltage (see D. 1. 1). If voltage
limiting (clamping) devices operate below 1,5 times the working voltage, the value of the applied voltage
is 0,9 times the clamping voltage, but not less than that of the working voltage. «A2
NOTE - In equipment which has ACCESSIBLE conductive parts connected to the PROTECTIVE CONDUCTOR TERMINAL. a
connection ran be made to the earth pin of the appliance inlet or mains plug. During this test. the equipment should
be electrically isolated from any external earthing means. «A2
The test voltage is raised to its specified value within 2 s and maintained for at least 2 s. «A2
No breakdown or repeated flashover shall occur. Corona effects and similar phenomena are disregarded.
«A2
发表于 2008-5-12 06:06:59 | 显示全部楼层
我建议大家都尽量以标准为依据,这样可以少花时间在无谓的争论上,并且结论的可信度一目了然。
发表于 2008-6-3 16:31:29 | 显示全部楼层
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