Example Of Calculating The Repeat Accuracy - Siemens SINUMERIK 840D sl Programming Manual

10.9

Example of calculating the repeat accuracy

10.9
Test program
This program allows the measuring scatter (repeat accuracy) of the entire measuring system
(machine-probe-signal transmission to NC) to be calculated.
In the example, ten measurements are taken in the X axis and the measured value recorded
in the workpiece coordinates.
It is therefore possible to determine the so-called random dimensional deviations which are
not subject to any trend.
Example
%_N_CHECK_ACCURATE_MPF
;$PATH=/_N_MPF_DIR
N05 DEF INT SIGNAL, KK
N10 DEF REAL MESSWERT_IN_X[10]
N15 G17 T1 D1
N20 ANF: G0 X0 F150
N25 MEAS=+1 G1 X50
N30 STOPRE
N35 SIGNAL= $AC_MEA[1]
N37 IF SIGNAL == 0 GOTOF_FEHL1
N40 MESSWERT_IN_X[kk]=$AA_MW[X]
N50 KK=KK+1
N60 IF KK<10 GOTOB ANF
N65 M0
N66 STOPRE
N70 M2
N80 _FEHL1: MSG ("Probe not switching")
N90 M0
N95 M2
Measuring cycles
Programming Manual, Release 04/2006, 6FC5398-4BP10-0BA0
10.9 Example of calculating the repeat accuracy
;Variable definition
;Start conditions, preselect tool offset
for
;probe
;Prepositioning in the measured axis
;Measurement at 1st measurement
;input with switching signal from "not
;deflected" to "deflected" in the X axis.
Probe switching expected between X0 and
X50.
;Stop decoding for subsequent
;evaluation of result (pre-processing
stop)
;Read software switching signal at
;1st measurement input
;Check switching signal
;Read measured value in workpiece
;coordinates
;Repeat 10 times
; preprocessing stop
Start-up (hardware)
10-27