10.5.12.3 Absolute Encoders - Siemens SINUMERIK 840D sl Commissioning Manual

10.5.12.3 Absolute encoders

Absolute encoder
Initial referencing of the measuring system of a machine axis with absolute encoder is
performed by calibrating the encoder.
Follow-up referencing
Follow-up referencing of a machine axis is performed automatically while the NC starts up
without axis movement. The following conditions must be fulfilled:
● The measuring system of the machine axis active after the booting of the NC works with
● The absolute encoder is calibrated:
Calibration
To calibrate the absolute encoder, the actual value of the encoder is matched with the
machine zero once and then enabled.
The SINUMERIK 840D sl supports the following types of calibration:
● Operator-assisted calibration
● Automatic calibration using probe
● Calibration using BERO
The calibration using the probe and BERO is described in:
Literature
Function Manual Basic Functions; Reference point approach: Automatic adjustment with
measuring probe, adjustment with BERO
Operator-assisted calibration
During operator-assisted calibration, the machine axis of the absolute encoder is moved to
the known machine position (reference position). The position value of the reference position
is taken over by the NC as the reference point value.
Recommended procedure
1. Parameterization of referencing mode
2. Approaching referencing position
IBN CNC: NCK, PLC, drive
Commissioning Manual, 07/2007, 6FC5397-2AP10-3BA0
the absolute encoder
MD34210 ENC_REFP_STATE[n] = 2 (absolute encoder is calibrated)
– MD34200 $MA_ENC_REFP_MODE[n] = 0
Traversing the machine axis to the referencing position in JOG mode. Approach direction
according to machine data:
– MD34010 $MA_REFP_CAM_DIR_IS_MINUS (reference point approach in minus
direction) (0 = positive, 1 = negative approach direction)
NCK start-up
10.5 Parameterize axis data
165