Set Reference Point; Incremental Approach Absolute (Mode 6) - Siemens SIMATIC S5 Manual

4.2.5

Set Reference Point

With the "set reference point" function, the axis is calibrated without movement. No hardware
limit switches and no precontact are required. The point at which the axis is located (actual posi-
tion) at the start of the "set reference point" function is assigned the reference point coordinate
programmed in the machine data record. Tool length and zero offsets are taken into account.
A reference point can be set at any axis position, even outside the hardware limit switches. You
must, therefore, make sure that your axis is in a permissible position within the hardware limit
switches before executing the "set reference point" function. Remember that the programmed
software limit switches may, under certain circumstances, be outside the hardware limit switches
mounted on the axis and therefore have no effect.
If a backlash compensation value is assigned other than O, the reference point must only be set
when there is no play in the drive. The first traversing movement (traversing distance greater
backlash is not yet taken into account with this traversing movement (=> Section 2,5.3.9
"BacklashCompensation").
4.2.6

Incremental Approach Absolute (Mode 6)

in this mode, a target specified in absolute coordinates is approached. If you select "O" in the
speed parameter, the speed of the approach is the speed specified in the machine data "in-
speed must, however, not exceed the maximum speed, (See "jog" modes 1, 2,) The target posi-
tion must be within the software limit switches or range limits, The mode can only be executed
when there is a reference point.
With a Iinearsxis the movement is triggered by the start command.
When operating a rotarysxis the terms below have the following meaning:
"Start" = approach the target by the shortest route.
If the distance is the same in both directions, the direction forwards (clockwise) has prior-
ity, Reversal backlash is in this case not taken into consideration. If the axis is already on
the target position, no movement is executed (=> Section 2,6.6.5 "Direction of Approach
to the Target Point with a Rotary Axis").
"Forward" = approaching the target in a forwards direction (clockwise direction), If the
axis is already on the target position, the total traversing range is covered once.
"Reverse" = approaching the target in a reverse direction (anti-clockwise direction). If the
axis is already on the target position, the total traversing range is covered once.
Changing the target while the axis is moving is not possible.
Description of the Individual Operating Modes
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