6 Applications
6.1.5
Methods 23 and 27: reference switch
These two methods use a reference switch which is active only over a certain part of the
distance. This method is particularly suitable for rotary axis applications in which the
reference switch is activated once during every rotation. If this method is used, the drive
moves in the positive direction (23) or negative direction (27) at search speed until it
reaches the reference switch. Then, the drive moves back at crawl speed and tries to find
the exact position of the reference switch. The home position refers to the falling edge of
the reference switch. If, at the beginning, the drive moves away from the reference switch,
the associated limit switch causes a reversal of the direction of rotation so that the
reference switch will be found.
Figure 36: Homing run to the reference switch
Product manual BL 4000-C
Page 76 of 298
