Question
Why is there a difference in the effect of surrounding metal between Shielded Proximity Sensors and Unshielded Proximity Sensors?
Answer
As shown in Figure 1, the surface of the detection coil on Shielded Proximity Sensors is covered with metal, so the flux is concentrated at the front of Sensors, which reduces the influence of surrounding metal.
As shown in Figure 2, the surface of the sensing coil on Unshielded Proximity Sensors is not covered with metal, so flux is also generated from the surface, which makes Sensors easily influenced by surrounding metal.