The coupling can be shifted into three positions;

  1. Electric motor engaged and hand drive disengaged. It is impossible to have the electric drive and manual drive engaged at the same moment. The electric mode can be used when all the proof printing has been done and the parameters like speed and pressure are known.
  2. Neutral position. In this position neither the electric drive, nor the manual drive are engaged. This position is used as a safety feature; whatever is activated on this press, the bed or rollers will not move.
  3. Manual drive. This position is normally used during proof printing, when parameters like speed and pressure have to be found.

The image on this page also shows the electric motor which is connected to the worm gear.