Siemens sinumerik 840d Programming Manual page 178

Special Motion Commands
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5.7 Extended measuring function MEASA, MEAWA, MEAC
840D 840D
NCU 571 NCU 572
NCU 573
Function
Axial measurement is available from SW version 4.
With this system, measurements can be taken
axially with several probes and several measuring
systems.
When MEASA, MEAWA is programmed, up to four
measured values are acquired for the programmed
axis in each measuring run and stored in system
variables in accordance with the trigger event.
MEASA and MEAWA are non-modal commands.
Continuous measuring operations can be executed
with MEAC. In this case, the measurement results
are stored in FIFO variables. The maximum number
of measured values per measuring run is also 4 with
MEAC.
Sequence
The measurements can be programmed in the part
program or from a synchronized action (Chapter 10).
Please note that only one measuring job can be
active at any given time for each axis.
Additional notes
• The feed must be adjusted to suit the measuring
task in hand.
• In the case of MEASA and MEAWA, the correctness
of results can be guaranteed only at feedrates with
which no more than one trigger event of the same
type and no more than 4 trigger events occur in each
position controller cycle.
• In the case of continuous measurement with
MEAC, the ratio between the interpolation cycle
and position control cycle must not exceed 8:1.
5-178
810D 840Di
CCU 2
SINUMERIK 840D/840Di/810D/FM-NC Programming Guide Advanced (PGA) − 04.00 Edition
04.00
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