Siemens SINUMERIK 840D Programming Manual page 71

03.96
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Description of parameters
See Section 2.1.2. (Drilling, Centering – CYCLE81)
for a description of parameters RTP, RFP, SDIS,
DP, DPR
DTB (dwell time)
You program the dwell time in seconds. It is only
active with tapping without encoder.
SDR (direction of rotation for retraction)
SDR=0 must be set if the spindle direction is to reverse
automatically.
If the machine data are defined so that no encoder is
set (machine data NUM_ENCS then has the value 0),
the parameter must be assigned the value 3 or 4 for the
direction of rotation, otherwise alarm
61202 "No spindle direction programmed" is issued and
the cycle is aborted.
SDAC (direction of rotation)
As the cycle can also be called modally (see Section
2.2), it requires a direction of rotation for tapping further
threads. This is programmed in parameter SDAC and
corresponds to the direction of rotation programmed
before the first call in the higher-level program. If
SDR=0, the value assigned to SDAC is of no
significance in the cycle and can be omitted from the
parameterization.
ENC (tapping)
If tapping is to be performed without encoder although
an encoder exists, parameter ENC must be assigned
the value 1.
However, if no encoder exists and the parameter is
assigned the value 0, it is ignored in the cycle.
 Siemens AG 2000 All rights reserved.
SINUMERIK 840D/840Di/810D/FM-NC Programming Guide, Cycles (PGZ) - 04.00 Edition
Drilling Cycles and Drilling Patterns
2.1 Drilling cycles
2
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