Profile Velocity

This mode operates the motor in Velocity Mode with extended (jerk-limited) ramps. Unlike Velocity Mode (see "Velocity"), the statusword is used in this mode to indicate whether the target speed is reached.

To activate the mode, the value "3" must be set in object 6060_h (Modes Of Operation) (see "CiA 402 Power State Machine").

The following bits in object 6040_h (controlword) have a special function:

• Bit 8 (Halt): If this bit is set to "1", the motor stops. On a transition from "1" to "0", the motor accelerates with the set start ramp to the target speed. On a transition from "0" to "1", the motor brakes and comes to a standstill.

The following bits in object 6041_h (statusword) have a special function:

• Bit 10 (target speed reached; Target Reached): In combination with bit 8 in the controlword, this bit specifies whether the target speed is reached, if braking is taking place or if the motor is at a standstill (see table).

  6041h Bit 10	6040h Bit 8	Description
  0	0	Target speed not reached
  0	1	Axis braking
  1	0	Target speed within target window (defined in 606Dhh and 606Eh)
  1	1	Axis speed is 0

• Bit 12: This bit indicates whether the actual speed is zero.

  If the actual speed is greater than the value in 606F_h(Velocity Threshold) for a time of 6070_h(Velocity Threshold Time), this bit has the value "0". The bit otherwise remains set to "1".

• Bit 13 (Deviation Error): This bit is set in closed loop mode if the slippage error is greater than the set limits (60F8h Max Slippage and 203Fh Max Slippage Time Out).

The following objects are necessary for controlling this mode:

• 606B_h (Velocity Demand Value):

  This object contains the output of the ramp generator, which simultaneously serves as the preset value for the velocity controller.

• 606C_h (Velocity Actual Value):

  Indicates the current actual speed.

• 606D_h (Velocity Window):

  This value specifies by how much the actual speed may vary from the set speed for bit 10 (target speed reached; Target Reached") in object 6041_h (statusword) to be set to "1".

• 606E_h (Velocity Window Time):

  This object specifies how long the actual speed and the set speed must be close to one another (see 606D_h "Velocity Window") for bit 10 "Target speed reached" in object 6041_h (statusword) to be set to "1".

• 607E_h (Polarity):

  If bit 6 is set to "1" here, the sign of the target speed is reversed.

• 6083_h (Profile acceleration):

  Sets the value for the acceleration ramp.

• 6084_h (Profile Deceleration):

  Sets the value for the deceleration ramp.

• 6085_h (Quick Stop Deceleration):

  Sets the value for the deceleration ramp for rapid braking.

• 6086_h (Motion Profile Type):

  The ramp type can be selected here ("0" = trapezoidal ramp, "3" = jerk-limited ramp).

• 60FF_h (Target Velocity):

  Specifies the target speed that is to be reached.

• The speed is is limited by 607F_h (Max Profile Velocity) and 6080_h (Max Motor Speed); the smaller value is used as the limit.