PANDOROS高压发生器J_（max）灯亮故障检修

Trouble-Shooting of "J_(max)" lighted in PANDOROS High Voltage Generator

本文分析了引发Ｊｍａｘ灯亮的三种原因．即Ｘ线管电流检测回路Ｒｓｓ电位计故障；ＫＶ参数值产生回路Ｖ２４管击穿故障，以及灯丝初级加热回路Ｖ２管软击穿故障，所以导致的高压发生器低电流保护，Ｊｍａｘ灯亮，不同的是前二项原因使曝光开始即刻Ｊｍａｘ灯亮，第三种原因使曝光过程中Ｊｍａｘ灯亮．

Three causes that can make 'Jmax' bight were analysed in the Paper. They arefault of the Potentiometer (R33) in the current detection circuitry of X-ray. the breakdown of the V24 in circuit of KV reference PCB, and the soft-breakdown of the V2 in the heating circuitof prdriary of Heater. All this may causes the low current protection. But the three reasons arediferent. The 'Jmax' is lighted the instant when exposure for first and second reason, and during the exposure for the third.