故障现象：开机一会儿透析液不吸，出现低电导报警，仪器无法使用。分析与检修：引起电导率异常主要来自三方面原因：①浓缩液配比；②讯号传感和指示系统；③比例泵系统。打开仪器后门，发现比例系中的活塞停在右边不动。由控制电路原理得知，（见图）左边的磁簧开关控制12VDC Symptoms: The dialysate does not absorb when the machine is switched on. A low conductivity alarm occurs and the instrument cannot be used. Analysis and Maintenance: Caused by abnormal conductivity mainly from three aspects: 1 ratio of concentrated liquid; 2 signal sensing and indication system; 3 proportional pump system. Open the back door of the instrument and find that the piston in the proportional system stops at the right side. According to the principle of the control circuit, the reed switch on the left (see figure) controls 12VDC