Positioning functionality

• Setup:
  Move the rapid-traverse or creep-speed axis into position at the touch of a button.
• Absolute incremental feed mode:
  The axis is moved to an absolute target position. The numerical values are stored in a table on the FM 351.
• Relative incremental feed mode:
  The axis is moved through a set route.
• Reference point motion:
  For synchronization after the PLC has been turned in when using incremental position encoders.
  

Special functions

• Zero offset
• Set reference point
• Delete distance to go
  

Mode of operation

Preparatory steps for a positioning task:

• Coordination of mechanical system and electronics:
  Easily achieved by entering machine data.
• Specification of target position and traversing speed via the S7 CPU or the configuring software
• Transfer of the interface signals from the CPU to the FM 351 (start, stop)

The FM 351 handles the actual positioning task:

• 4 digital outputs controlling the rapid-traverse, creep-speed, counterclockwise and clockwise functions are assigned to each channel.
• Creep speed or rapid-traverse/creep speed is specified depending on the distance to the target.
• After the cutoff point is reached, the module monitors the target approach. After the target area is reached, a signal is sent to the CPU.