现在有些精密的医疗仪器要求相线 (火线 )与零线不可反接。对于专业人员可以很容易的用试电笔测出来 ,但对于使用医疗仪器的医护人员 ,往往容易忽视这一点 ,造成一些不必要的损失。因此 ,为这类仪器配备一个专用可变相线插座是图　电路原理图很重要的。现将自制自动变相线插座 Some sophisticated medical instruments now require that the phase line (FireWire) and the neutral line must not be reversed. For professionals, it can be easily measured using a test pencil. However, for medical personnel who use medical instruments, it is easy to overlook this and cause some unnecessary losses. Therefore, it is very important to provide a dedicated variable phase line socket for this type of instrument. Now self-made automatic phase change line socket