8.  SETUP SERVOGUN OVERTORQUE PROTECTION Screen

Table 8, " SETUP SERVO GUN OVERTORQUE PROTECTION Screen Items " lists and describes items found on the Overtorque Protection screens.

Table 8.  SETUP SERVO GUN OVERTORQUE PROTECTION Screen Items

Item Description / notes
OVERTORQUE PROT MAIN Screen Items
OverTorque Protection This item specifies whether the Overtorque Protection function is on or off. Set to ENABLE to use the protection, set to DISABLE to turn off the protection.
Sensitivity This item specifies the % sensitivity for Overtorque Protection. 100% is the standard sensitivity. Protection is more sensitive with a higher value. A value from 1-200% may be specified.
Parameter Summary The overtorque protection parameters are displayed in this screen.
OverTrq protection enabled: DO[0] This item specifies a Digital Output to turn ON when overtorque protection is enabled.
OverTrq condition detected: DO[0] This item specifies a Digital Output to turn ON when overtorque condition is detected.
Jog velocity limit (mm/sec): This item specifies a jog velocity limit for the servo gun. The maximum value for this item is 250mm/sec. A lower value will limit the jogging speed.
OVERTORQ PARAM SUMRY Screen Items
Display Units The user can specify the display units for the Overtorque Parameters
  • TorqCt = Torque counts are the internal operating units for the software. Torque Counts can be converted to motor current based on the preceding equation

  • Force = the TorqCt is converted to a unit of force based on the existing Pressure Calibration data

Max Gun Torque This is the maximum collision torque that OverTorque Protection will allow for the servo gun axis. This value corresponds to the torque that will yield the Max Pressure, as specified on the servo gun general setup screen, plus a small margin. Max gun torque is the value at which the overtorque alarm triggers. Therefore, the margin should be specified so that Max gun torque is slightly larger than the max torque observed during close (transient torque) and hold (static torque). The magnitude of the margin is specified by the system variable $sggun#.$chk_prs.$margin_p and is in units of kgf
Std OverTorque Value This is the standard collision detection torque. This value is derived from measurement of the static friction during autotuning. When sensitivity is set to 100%, all OverTorque thresholds except the program close stroke (used for pressuring) will be set to this value. Sensitivity adjustment will adjust the OverTorque thresholds around the Std OverTorque value. See the equation for how sensitivity adjustment affects the Overtorque thresholds.
Max Motor Torque: This is NOT an OverTorque limit. This value represents the maximum motor torque available from the amplifier for standard motion, such as acceleration and deceleration.
OverTorque thresholds The following values display the actual OverTorque parameters for the (4) different types of servo gun motion. These represent the actual torque value at which a Collision Alarm will be issued.
Program Close Stroke This is the limit for program close motion, which is for performing pressuring operations. The value corresponds to the torque that yields the Max Pressure specified for the gun. This value can only be adjusted by changing the Max Pressure. Since pressuring operations require large torque, this value is always equal to the Max Gun Torque.
Program Open Stroke This is the limit for open motion of the gun during program operation. This is based on the Std OverTorque Value and the Sensitivity
Jog Close Stroke This is the limit for close motion of the gun during jogging operation. This is based on the Std OverTorque Value and the Sensitivity
Program Open Stroke This is the limit for open motion of the gun during jogging operation. This is based on the Std OverTorque Value and the Sensitivity