程控交换机过电流保护元件的研制

A Study on Over Current Protective Component for Program Controlled Switchboard

介绍了低电阻率陶瓷ＰＴＣ的设计方法及研制过程，并按照邮电部行业标准对这一实用课题的研制结果进行了分析与讨论．生产的实践证明，用国产原料、国产设备完全可以生产出这类难度较大的自复性过流保护元件．

The background of the research project of self restoring over current protective component for communication equipment and the design method as well as the development of a kind of low resistivity ceramic PTC are described. Using highly purified chemical materials and with low harmful impurities such as K, Na, Mg and Fe, adopting the formulation of (0.86～0.90) BaCO 3+(0.14～ 0.10 ) SrCO 3+1.0TiO 2+STAL+YNb+Mn(NO 3) 2, together with controlled sintering technology and Al Ag electrodes, PTC over current protective components completely comformed to the Professional Standard of the Ministry of Post and Telecommunication, P.R.China have been prepared. According to the results of selective examination (Report No.96222) by the National Quality Control Department, the actual levels of the components are listed.