HEIDENHAIN ND 287 User Manual - Manual (Page 56)

56
I Working with the ND 287 position display unit
I – 5 Ser
ies of measur
ements and statistical
pr
ocess
c
ontr
ol Starting and stopping SPC
Danger to workpiece!
 If the measured value falls below or exceeds the
control limits
during statistical process control, the
ND 287 displays a warning and switches the display to
the respective control chart. The ND does not stop data
acquisition.
 If a measured value falls below or exceeds the defined
tolerance limits
, the ND displays the appropriate
sorting symbols and the display value in red if you have
activated this display color. Pin 17 or pin 18 at D-sub
connection X41 are active.
 When you press START SPC, the ND 287 automatically
resumes measured-value recording for the SPC that
was last active. The previously measured sample values
are retained in the FIFO memory. The memory is only
cleared if you change the SPC settings in the SAMPLES
or TOLERANCES form, or if you delete the measured
values with the DELETE STATISTIC parameter (see
"Deleting SPC statistics" on page 55).
 A new SPC cannot be started until the current SPC has
been completed and the measured values recorded
have been deleted (see "Deleting SPC statistics" on
page 55).
The measured values and the data of the diagrams and
control charts always apply to the currently active
display mode
(see "Axis display mode" on page 27):
 In display mode X1, the SPC data applies to the
encoder at input X1.
 In display mode X2, the SPC data applies to the
encoder at input X2.
 In display mode X1:X2, the SPC data applies to the
defined coupled position value (X1+X2, X1-X2 or
f(X1,X2).