Siemens SINUMERIK 840D sl Function Manual page 703

MEAC
Continuous, axial measurement without deletion of distance-to-go
MEAC[axis] = (mode, measurement memory, trigger event 1, trigger event 2, trigger event 3,
trigger event 4)
Parameter description:
● Axis: Channel axis name (X, Y, ...)
● Mode:
● Measurement memory: Number of FIFO
● Trigger event:
The axial measured values are available in the machine coordinate system (MCS). They are
written to a FIFO variable defined by the user, e.g. $AC_FIFO1. When two probes have been
projected for the measurement, the measured values of the second probe are saved
separately in the subsequent FIFO.
The number of measured values is limited by the following machine data:
MD28264 LEN_AC_FIFO
Variables $AC_MEA and $AA_MM are therefore irrelevant.
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
– Units decade
0 = abort measurement job
(for synchronized actions)
1 = up to 4 trigger events can be activated concurrently
(a max. of 4 signals can be triggered concurrently in one position control clock cycle,
however the sequence must be kept)
2 = up to 4 trigger events can be activated successively
(per position control clock cycle, only one signal can be triggered)
– Decade (= encoder selection)
0/not set = use active measuring system
1 = 1st measuring system
2 = 2nd measuring system
(if available, otherwise the first measuring system is used; no alarm is generated)
3 = 1st and 2nd measuring system
If two measuring systems are used to take the measurement, a maximum of two trigger
events may be programmed.
1 = rising edge of probe 1
-1 = falling edge of probe 1
2 = rising edge of probe 2
-2 = falling edge of probe 2
Measurement (M5)
Axial measurement (optional)
703