# Empirical Value, Mean Value: _evnum - Siemens SINUMERIK 840D sl Programming Manual

Measuring cycles hmi sl.

Parameter description
2.3 Description of the most important defining parameters
Parameters
Value of _PRNUM: >0, integer
_PRNUM can only have three digits in workpiece measurement. In that case the most
significant digit is evaluated as the probe type.
The two least significant digits represent the probe number.
Digit
3
0
1
Example of workpiece measurement
_PRNUM
Example of tool measurement
_PRNUM
2.3.14

## Empirical value, mean value: _EVNUM

General information
The effect of empirical and mean values is described in the chapter "General section,
measuring principle and measurement strategy".
The empirical values and mean values are stored in data block (GUD5) in arrays
● _EV[ ] empirical values and
● _MV[ ] mean values.
The unit of measurement is mm in the metric basic system and inch in the inch basic system,
irrespective of the active system of units.
The number of existing empirical and mean values is entered in data block (GUD6)
_EVMVNUM[ m,n].
● m: array dimension _EV[m]
● n: array dimension _MV[n]
The default setting provides 20 values each (array index _EV, _MV: 0...19).
80
Meaning
2
1
Probe number (two digits)
Multi probe
Mono probe
= 102
→ Probe type
→ Probe number
→Array index
= 3
→ Probe number
→Array index
Mono probe
2
_WP[1,n]
3
_TP[2,n]
Programming Manual, 03/2009 Edition, 6FC5398-4BP10-2BA0
Measuring cycles