Electrolux FOM 71 CLS Maintenance Manual page 62

15:2
Installation of speed sensor
A speed sensor can be attached to the end of the drum shaft. To facilitate
attaching the sensor, a hole can be made in the back panel of the machine.
A diameter of less than 60 mm will not affect machine performance. (Venti-
lation holes may change the air temperature inside the machine, which may
also affect water temperature).
Installation of laboratory sensors