从3脚输入来的电流信号是4~20mA一直都是正的,这里为什么要-12V的电源,这个可以单电源+12v供电吗?4脚直接接地
This thread has been locked.
If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.