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HEIDENHAIN
Working with the measured
value display unit
Actual value and input display
(7-segment LED,
9 decades and sign)
• Select datum
• Page backward in
parameter list
ND 261
• Confirm entry value
• Set display to value from
P79 (P80!)
Numeric keypad
789
456
REF21 SET
=
<>
HEIDENHAIN
Status display
• Output measured value over data
interface (P86!)
• Go to parameter list after switch-on
• Page forward in parameter list
Indicator Meaning
REF If decimal points are blinking:
Display is waiting for the reference mark to be crossed over.
If decimal points are not blinking: Reference mark was crossed
over — datum points are now stored in nonvolatile memory.
Blinking: Waiting for operator to press ENT or CL.
1 / 2 Datum 1 / Datum 2 currently active.
• Clear entry
• Reset to zero (P80!)
• CL plus MOD:
parameter list
• CL plus 2-digit number: select parameter
• Clear parameter entry
and show parameter
number
MOD
123
0
CL
.
–
• Algebraic
sign
• Decrease
parameter
value
• Decimal point
• Increase parameter value
SET Blinking: Waiting for operator to confirm entry values.
< / = / > Sorting mode: Measured value less than lower limit /
within tolerance / greater than upper limit.
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The ND 261 is designed for use with HEIDENHAIN angle encoders with sinusoidal
output signals: either ND 261A for 11 µA
(Id. Nr. 322 352 ..). These angle encoders have one reference mark or several
distance-coded
When a reference mark is crossed over, it generates a signal identifying that position
as a reference point. After switch-on, simply crossing over a reference mark
restores the relationship between axis positions and display values as it was last
defined by datum setting.
With distance-coded reference marks, a maximum traverse of only 10° or 20°
suffices to restore the datum.
reference marks.
(Id. Nr. 283 482 ..) or ND 261V for 1 V
PP
Switch-On
PP
0 ➤1
Ent...CL
5 , 6 9 7
If you do not wish reference mark evaluation, press CL instead of ENT.
Turn on the power (switch located on rear panel).
• Display shows .
• REF blinks.
Switch on reference mark evaluation
• Display shows the value last assigned to the
reference mark position.
• REF indicator glows.
• Decimal point blinks.
Cross over reference mark
Move the axis until the display becomes active and the
decimal point no longer blinks.
Setting the Datum
The datum setting procedure assigns a display value to a specific axis position.
The ND 261 allows you to set two separate datum points.
Select datum 1 or 2.
Enter a value, such as 40.
4 0
Confirm entered value.
You can switch from one datum to the other at any time.
Use datum 2 when you want to display incremental dimensions.
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Sorting and Tolerance Check Mode
In this mode, the display value is compared with an upper and a lower limit value.
Status indicators and the trigger signal outputs at the D-sub EXT connection (see
that section) indicate whether the display value is less than the lower limit, greater
than the upper limit, or between the two limit values.
Indicator Meaning
= Measured value is between the limit values
< Measured value is less than the lower limit value
> Measured value is greater than the upper limit value
Operating parameters for the sorting mode:
• P17: Sorting on/off
• P18, P19: Limit values