Method for monitoring railway points and points machine

A switch drive comprising:

• a housing;
• a switch setting motor arranged in the housing;
• a switch rod extending out of the housing for coupling to a track switch;
• a piezoelectric sensor arranged on the housing;
• and
• an evaluation unit to which the measurement signals of the piezoelectric sensor are fed, the evaluation unit configured to detect and record measurement signals of the piezoelectric sensor;
• wherein periodic components of the measurement signal are at least partially filtered out to obtain signal components representative of a non-periodic change in the strain of the housing;
• and
• wherein the evaluation unit is configured to detect the signal components representing the non-periodic change of the strain by determining the quasi-static parts of the sensor pickup, and the evaluation unit is configured to evaluate a temporal progression of the signal components representative of the non-periodic change in the strain to identify deviations from a nominal state.