Air Pumps On的意思|示意

气泵开启 Speakers of other company uses YJB8-50-disc package native, in use by all of a sudden no book block, as long as machines, air pumps on, would ground cover, I suspect that the reflective photoelectric switch has a problem, it is E3JK-R4M1, principle as in Figure 3: detection with a piece of white, the corresponding output voltage, there is no problem there.