Some sensors have relay contact outputs. The maximum switching power and the electrical design can be found in the technical data of each sensor.
The information about the mechanical service life is of particular interest in this version. This refers to the number of switching cycles of the unloaded relay contact. This value is also achieved with low electric contact load. The value is reduced to the specified value of the electrical endurance at nominal load on the contacts. The service life values are MTBF values (MTBF = mean operating time between failures).
Sensors with relay contact output are used when high load currents are required and/or when galvanic isolation between the sensor circuit and the load current circuit is required. Since relay contacts are always accompanied by moving masses, the maximum switching frequency is limited to a few switching cycles per second. This limits the use of sensors with relay contacts to more static applications.
Sensors with relay contact output are marked with an R in the third block of the Pepperl+Fuchs order designation.
Take a look at the range of Pepperl+Fuchs inductive sensors.