Operating instructions

Functions, monitoring, and protective functions
9.4 Extended functions
Drive converter cabinet units
Operating Instructions, 10/2008, A5E00288214A
381
9.4.6.3 Referencing
Description
Once a machine has been switched on, the absolute dimensional reference to the machine’s
zero point must be established for positioning purposes. This procedure is referred to as
referencing.
The following types of referencing are available:
● Setting reference point (all encoder types)
● Active referencing (reference point approach (p2597 = 0), with incremental encoder):
– Referencing cam and encoder zero mark (p2607 = 1)
– Encoder zero mark (p0495 = 0)
– External zero mark (p0495 ≠ 0)
● Flying referencing (passive (p2597 = 1), with incremental encoder)
● Absolute encoder adjustment (with absolute value encoder)
● Flying referencing (passive (p2597 = 1), with absolute encoder)
A connector input is provided for the specification of reference point coordinates for all types
of referencing. This allows e.g. for modification/specification by means of higher-level
control. An adjustable parameter for this variable is however needed for the fixed
specification of reference point coordinates. This adjustable parameter p2599 is connected
to connector input p2598 as standard.
Note
Referencing of distance-coded zero marks is not supported.
Set reference point
The reference point can be set by a 0/1 edge on binector input p2596 (set reference point) if
no other traversing block is active or has been interrupted by an interim stop. The current
actual position of the drive is set here as the reference point using the coordinates specified
by connector input p2598 (reference point coordinates). The setpoint (r2665) is adjusted
accordingly.
This function also uses actual position value correction for the position controller (p2512 and
p2513). Connector input p2598 is connected to adjustable parameter p2599 as standard.
The binector input is not effective for the traversing task being presently executed.
Absolute encoder adjustment
Absolute encoders have to be adjusted during commissioning. Once the machine has been
switched off, the encoder’s position information is retained.
With the aid of the reference point coordinates in p2599 and by entering p2507 = 2, an offset
value (p2525) is calculated and is then used to calculate the actual position value (r2521).
Parameter p2507 reports calibration using a "3". Bit r2684.11 (reference point set) is also set
to "1".