Siemens sinumerik 808d Programming And Operating Manual page 130

Cycles
2.4 Drilling cycles
Explanation of the parameters
For an explanation of the parameters RTP, RFP, SDIS, DP, and DPR, refer to the topic
"Drilling, centering - CYCLE81 (Page 112)".
DTB (dwell time)
The dwell time must be programmed in seconds. It is only effective in 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 is defined such that no encoder is set (in this case, machine data
MD30200 $MA_NUM_ENCS is 0), the parameter must be assigned the value 3 or 4 for the
direction of rotation; otherwise, alarm 61202 "No spindle direction programmed" is output
and the cycle is aborted.
SDAC (direction of rotation)
Because the cycle can also be called modally (see section "Graphical cycle support in the
program editor (Page 107)"), it requires a direction of rotation for tapping further threaded
holes. 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 has no meaning in the cycle and can be omitted in the parameterization.
ENC (tapping)
If tapping is to be performed without encoder although an encoder exists, parameter ENC
must be assigned value 1.
If, however, no encoder is installed and the parameter is assigned the value 0, it is ignored in
the cycle.
MPIT and PIT (thread lead as a thread size and as a value)
The parameter for the lead is only relevant if tapping is performed with encoder. The cycle
calculates the feedrate from the spindle speed and the lead.
130
Turning Part 2: Programming (Siemens instructions)
Programming and Operating Manual, 05/2012, 6FC5398-5DP10-0BA0