User Manual

Motion control is easy
10.6 Operation of motion control for S7-1200
Easy Book
250 Manual, 03/2014, A5E02486774-AF
Parameter
Description
Reference point switch
(Active and passive homing)
• Active homing: Select whether the axis is to be referenced on the left or right side
of the reference point switch. Depending on the start position of the axis and the
configuration of the homing parameters, the reference point approach sequence
can differ from the diagram in the configuration window.
• Passive homing: With passive homing, the traversing motions for purposes of
homing must be implemented by the user via motion commands. The side of the
reference point switch on which homing occurs depends on the following factors:
– "Approach direction" configuration
– "Reference point switch" configuration
– Current travel direction during passive homing
Approach velocity
(Active homing only)
Specify the velocity at which the reference point switch is to be searched for during
the reference point approach.
Limit values (independent of the selected user unit):
Start/stop velocity ≤ approach velocity ≤ maximum velocity
Reduced velocity
(Active homing only)
Specify the velocity at which the axis approaches the reference point switch for
homing.
Limit values (independent of the selected user unit):
Start/stop velocity ≤ reduced velocity ≤ maximum velocity
Home position offset
(Active homing only)
If the desired reference position deviates from the position of the reference point
switch, the home position offset can be specified in this field.
If the value does not equal 0, the axis executes the following actions following
homing at the reference point switch:
1. Move the axis at reduced velocity by the value of the home position offset.
2. When the position of the home position offset is reached, the axis position is set
to the absolute reference position. The absolute reference position is specified via
parameter "Position" of motion control instruction "MC_Home".
Limit values (independent of the selected user unit):
-1.0e12 ≤ home position offset ≤ 1.0e12
Table 10- 38 Factors that affect homing
Influencing factors:
Result:
Configuration
Approach direction
Configuration
Reference point switch
Current travel direction
Homing on
Reference point switch
Positive "Left (negative) side"
Positive direction
Left
Negative direction Right
Positive "Right (positive) side"
Positive direction
Right
Negative direction
Left
Negative "Left (negative) side"
Positive direction
Right
Negative direction
Left
Negative "Right (positive) side"
Positive direction
Left
Negative direction
Right