Siemens SINUMERIK 840Di Function Manual page 344

Detailed Description
2.1 General functionality
The new torque in consideration of the ramp
(MD37012 FIXED_STOP_TORQUE_RAMP_TIME)
interpolation cycle takes effect after the change in the drive.
A change of the effective torque can be checked by reading the synchronized action variable
$VA_TORQUE[axis].
2.1.6 Travel with limited moment/force FOC:
Function
For applications in which torque or force are to be changed dynamically depending on the
travel or on the time or on other parameters (e.g. pressing), the following functionality FOC
(Force Control) is provided.
Force/travel or force/time profiles are thus possible using the "Interpolation cycle" resolution.
The function allows torque/force to be modified at any time using synchronized actions.
The function can be activated modally or blockrelated.
Modal activation (FOCON/FOCOF)
The activation of the function after POWER_ON and RESET is determined by the machine
parameter:
MD37080 FOC_ACTIVATION_MODE.
Table 2-1
Bit 0
Bit 1
FOCON: Activation of the modally effective torque/force limitation
FOCOF: Disable torque/force limitation
The modal activation acts beyond the program end.
If already programmed, it is effective with FXST set torque/force.
FXST can be programmed irrespectively of FOCON; it comes into effect, however, only after
the function has been activated.
2-20
Controlling the initial setting of the modal limitation of torque/force
After
Power On
RESET
Value
0
1
0
1
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Effect
FOCOF
FOCON
FOCOF
FOCON
Travel to Fixed Stop (F1)