Influence of environmental conditions [t-head2]

As can be seen from the following diagram, the switching distance S_r is dependent on the dielectric constant ε_r of the object to be monitored.

Metal objects produce the maximum switching distance (100 %).

With other materials, it is reduced relative to the dielectric constant of the object to be monitored.

The following table lists the dielectric constants ε_r of some important materials. Due to the high dielectric value of water, the fluctuations with wood can be significant. Damp wood therefore is registered much more effectively by capacitive proximity switches than dry wood.