Siemens sinumerik 840D sl Operating Manual page 297

Parameters
D1 or ND
(only for ∇ and
∇ + ∇∇∇)
rev
NN
VR
Multiple threads
Parameters, G code program (thread, face)
PL Machining plane
SC Safety clearance
F Feedrate
Turning
Operating Manual, 07/2010, 6FC5398-8CP40-0BA0
Description
First infeed depth or number of roughing cuts
The respective value is displayed when you switch between the number of
roughing cuts and the first infeed.
Finishing allowance in X and Z – (only for ∇ and ∇ + ∇∇∇)
Number of noncuts - (only for ∇∇∇ and ∇ + ∇∇∇)
Return distance (inc)
No
α0 Starting angle offset
Yes
N Number of threads
The threads are distributed evenly across the periphery of the
turned part; the first thread is always placed at 0°.
DA Thread changeover depth (inc)
First machine all thread turns sequentially to thread changeover
depth DA, then machine all thread turns sequentially to depth 2 ·
DA, etc. until the final depth is reached.
DA = 0: Thread changeover depth is not taken into account, i.e.
finish machining each thread before starting the next thread.
Complete, or
Machining: 
from turn N1

N1 (1...4) start thread N1 = 1...N
only thread NX

NX (1...4) 1 from N threads
mm
mm/min
Programming technology functions (cycles)
or
Parameters, ShopTurn program (thread, face)
T Tool name
D Cutting edge number
F Feedrate
S / V Spindle speed or constant
cutting rate
8.2 Rotate
Unit
mm
mm
mm
mm/min
mm/rev
rpm
m/min
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