测绕组我们现在也是直接接欧姆表,以前是用电桥,但这个我用起来不顺,还是喜欢欧姆表,有同事将欧姆表跟示波器相连,断电并街上欧姆表后的电阻值曲线就能在示波器上读出,但现在没有好的计时方法,样品断电和示波器的计时同步问题还没解决,断电的零点有明显误差,最终倒推回去的曲线的零点电阻误差也较大,这个不晓得有没有人有办法解决。
另外想再问下ctl决议里关于一般性测温升的达到稳定的判断的文件是哪个。 我也想参加讨论,但本人的知识水平太差,只能一点一点的学习大师们的知识。我看了大家的发言,有时在想有些不好测量的地方,可否用精度较高的红外测试仪进行定时、定点的的进行测试,不知可否。 我们一般用keithly的,安捷伦的好像娇气了点 引用第68楼jean1985于2007-11-03 15:05发表的:
有没有做过高压清洗机的温升实验的?
汽油机或柴油机运转时间较长后,水泵的温度就会很高,要如何控制和调节才能通过安全测试呢
清洗機的標準ul似乎是ul1776, 但這各台式工具好象溫度要求會比手持式的會松很多. 壓縮當然會產生熱量, 這是不可避免的. IEC60335-2-14的讨论
搅拌器(立式用手保持开关)的温升测试标准下面怎么理解?
假设现在有一个搅拌器(立式用手保持开关)说明书上要求的工作时间不超过30sec,那么做温升是按下面那一种说法做。
11.7 Replacement:
The appliance is operated for the period specified. However, if this period exceeds that stated in the instructions and if the temperature rise limits of Table 3 are exceeded, the test is carried out with the maximum quantity of ingredients stated in the instructions as follows:
– the maximum period stated in the instructions plus 1 min, for specified operating periods not exceeding 7 min;
– the maximum period stated in the instructions, for specified operating periods exceeding 7 min.
If it is necessary to perform a number of operations to obtain these periods, the rest periods are equal to the time taken to empty and refill the container.
Appliances incorporating a timer are operated for the maximum period allowed by the timer.
11.7.103 Blenders that have to be kept switched on by hand and hand-held blenders are operated for 1 min with the control adjusted to the highest setting. The operation is carried out five times with rest periods of 1 min during which the mixture is replaced.
For other blenders, the period of operation is 3 min, the operation being carried out 10 times.
60950单一故障的温升
谁能介绍下IEC/EN60950在做开关电源时,做单一故障测试时,什么情况下需要跑温升? 关于测温升的方法,我以前有做过马达的是采用热电偶法。布点方法是马达主付绕组各两根,且要在不同的端面。
热电偶用专用胶水连接到绕组上。 现在横河有款温度仪直接可以带电测量,但价格实在太高.
另外关于测试角的制作及热电偶的要求CTL有决议,要求热电偶的焊接长度为1.5mm,铜片的距离为20mm,推荐使用的热电偶为K型及J型