Siemens Sinumerik 840DiE sl - Page 357

01/2007
11.5 Axes and spindles
11-357
© Siemens AG 2007 All Rights Reserved
SINUMERIK 840Di sl Manual (HBIsl) – 01/2007 Edition
!
Warning
If the reference cam is not calibrated exactly, it is possible that a wrong zero
marker is evaluated after the reference cam has been left. As a result, the
control system will take a wrong machine zero.
Software limit switches, protection areas and work area limits will thus also be
active for the wrong positions. The difference is equivalent to  one encoder
revolution in each case.
Danger for man and machine exists.
The following machine data and interface signals are important:
S MD34040: REFP_VELO_SEARCH_MARKER (creep velocity)
S MD34050: REFP_SEARCH_MARKER_REVERSE (direction reversal to
reference cam)
S MD34060: REFP_MAX_MARKER_DIST (maximum distance from cam to
reference mark)
Properties of phase 2:
S Feed override (the feed override switch) is not active.
If a feed override of 0% is selected via the feed override switch, the traverse
movement is stopped.
S Feed stop (channel–specific and axis–specific) is active.
On a feed stop, the traverse movement is stopped and the following alarm
displayed:
S Alarm 20005 ”Reference point approach canceled”
S NC–Stop/NC–Start is inactive.
S If the machine axis travels as from exiting the reference cam:
S IS: DB31, ... DBX12.7 (”Reference point approach delay”) = 0
a max. distance parameterized in the machine data:
S MD34060: REFP_MAX_MARKER_DIST (max. distance to the reference
mark)
without the zero mark being detected, the machine axis stops and the fol-
lowing alarm is displayed:
S Alarm 20002 ”Zero mark missing”
Phase 2:
Synchronizing to the
encoder zero marker
11 NCK Commissionin
g
with HMI Advanced