Siemens Sinumerik 840D sl Programming Manual page 40

Flexible NC programming
1.1 Variables
<unit>
1) The physical unit is dependent on the axis type: linear or rotary axis.
2) System of units changeover
G70/G71(inch/metric)
After changing over the basic system (MD10240 $MN_SCALING_SYSTEM_IS_METRIC) with G70/
G71, for read/write operations to system and user variables involving a length, then the values are not
converted (actual value, default value and limit values)
G700/G710(inch/metric)
After changing over the basic system (MD10240 $MN_SCALING_SYSTEM_IS_METRIC) with G700/
G710, for read/write operations to system and user variables involving a length, then the values are
converted (actual value, default value and limit values)
3) The variable is not converted to the NC's current measuring system (inch/metric) automatically.
Conversion is the sole responsibility of the user/machine manufacturer.
Note
Level overflow due to format conversion
The internal storage format for all user variables (GUD/PUD/LUD) with physical units of
length is metric. Excessive use of these types of variable in the NCK's main run, e.g in
synchronized actions, can lead to a CPU time overflow at interpolation level when the
measuring system is switched over, generating alarm 4240.
40
Meaning
30
Peripheral speed
31 Resistance
32 Inductance
33 3)
Torque
34
Torque constant
35 Current controller gain
36
Speed controller gain
37 Speed
42 Power
43 Current, low
46
3)
Torque, low
48 Per mil
49 -
65 Flow rate
66 Pressure
67
3)
Volume
68
Controlled-system gain
69 Force controller controlled-system gain
155
3)
Thread lead
156
Change in thread lead
2)
3)
3)
3)
3)
Programming Manual, 02/2011, 6FC5398-2BP40-1BA0
Physical unit
[ m/s], [ feet/s ]
[ ohm ]
[ mH ]
[ Nm ]
[ Nm/A ]
[ V/A ]
[ Nm/(rad*s) ]
[ rpm ]
[ kW ]
[ μA ]
[ μNm ]
-
[ Hz/s ]
[ l/min ]
[ bar ]
3
[ cm ]
[ mm/(V*min) ]
[ N/V ]
[ mm/rev ], [ inch/rev ]
[ mm/rev / rev ], [ inch/rev / rev ]
Job planning