PURPOSE: To detect the abnormality in stopping irrespectively of the stop position of a slide by comparing the reference value obtained by adding a prescribed value to the standard slip value of a press and the actual slip value when the press stops.

CONSTITUTION: A prescribed value permissible in terms of stability is added to a standard slip value of a press to set a standard value, at which the press is started and the slide is driven. The presence or absence of a command for transmitting a clutch off signal or the presence or absence of a command for stopping the press is judged from the revolutions of an eccentric shaft or the movement of a reciprocating member by driving of the slide. When the command for stopping the slide is transmitted in order to turn the clutch off, the position for the rotating angle of the eccentric shaft or the moving position of the reciprocating member when said command is transmitted is stored in a microcomputer. When the slide is stopped by the command for stoppage, the rotating angle of the eccentric shaft or the moving position of the reciprocating member when the slide stops is read by the computer. The actual slip value of the slide is operated and is compared with the reference value.