Delta Tau GEO BRICK LV Reference Manual
Turbo PMAC/PMAC2 Software Reference
Turbo PMAC Global I-Variables
112
On a typical system with a current-loop amplifier and PMAC's default servo update time (~440
sec), an
Ixx31 value of 2000 to 3000 will provide a critically damped step response.
If the servo update time is changed, Ixx31 must be changed proportionately in the opposite direction to
keep the same damping effect. For instance, if the servo update time is cut in half, from 440
keep the same damping effect. For instance, if the servo update time is cut in half, from 440
sec to 220
sec, Ixx31 must be doubled to keep the same effect.
This parameter is usually set initially using the Tuning utility in the PMAC Executive Program. It may be
changed on the fly at any time to create types of adaptive control.
changed on the fly at any time to create types of adaptive control.
Ixx31 is not used if Iyy00/50 for the motor has been set to 1 to enable the Extended Servo Algorithm
(ESA) for the motor.
(ESA) for the motor.
Ixx32 Motor xx PID Velocity Feedforward Gain
Range:
-8,388,608 - 8,388,607
Units:
(Ixx30*Ixx08)/2
26
16-bit output bits / (counts/servo update)
Default:
1280
Ixx32 adds an amount to the control output proportional to the desired velocity of Motor xx. It is
intended to reduce tracking error due to the damping introduced by Ixx31, analog tachometer feedback, or
physical damping effects.
intended to reduce tracking error due to the damping introduced by Ixx31, analog tachometer feedback, or
physical damping effects.
If the motor is driving a current-loop (torque) amplifier, Ixx32 will usually be equal to (or slightly greater
than) Ixx31 to minimize tracking error. If the motor is driving a velocity-loop amplifier, Ixx32 will
typically be substantially greater than Ixx31 to minimize tracking error.
than) Ixx31 to minimize tracking error. If the motor is driving a velocity-loop amplifier, Ixx32 will
typically be substantially greater than Ixx31 to minimize tracking error.
If the servo update time is changed, Ixx32 must be changed proportionately in the opposite direction to
keep the same effect. For instance, if the servo update time is cut in half, from 440
keep the same effect. For instance, if the servo update time is cut in half, from 440
sec to 220
sec,
Ixx32 must be doubled to keep the same effect.
This parameter is usually set initially using the Tuning utility in the PMAC Executive Program. It may be
changed on the fly at any time to create types of adaptive control.
changed on the fly at any time to create types of adaptive control.
Ixx32 is not used if Iyy00/50 for the motor has been set to 1 to enable the Extended Servo Algorithm
(ESA) for the motor.
(ESA) for the motor.
Ixx33 Motor xx PID Integral Gain
Range:
0 - 8,388,607
Units: (Ixx30*Ixx08)/2
42
16-bit output bits / (counts*servo update)
Default:
1280
Ixx33 adds an amount to the control output proportional to the time integral of the position error for
Motor xx. The magnitude of this integrated error is limited by Ixx63. With Ixx63 at a value of zero, the
contribution of the integrator to the output is zero, regardless of the value of Ixx33.
Motor xx. The magnitude of this integrated error is limited by Ixx63. With Ixx63 at a value of zero, the
contribution of the integrator to the output is zero, regardless of the value of Ixx33.
No further errors are added to the integrator if the output saturates (if output equals Ixx69), and, if
Ixx34=1, when a move is being commanded (when desired velocity is not zero). In both of these cases,
the contribution of the integrator to the output remains constant.
Ixx34=1, when a move is being commanded (when desired velocity is not zero). In both of these cases,
the contribution of the integrator to the output remains constant.
If the servo update time is changed, Ixx33 must be changed proportionately in the same direction to keep
the same effect. For instance, if the servo update time is cut in half, from 440
the same effect. For instance, if the servo update time is cut in half, from 440
sec to 220
sec, Ixx33
must be cut in half to keep the same effect.
This parameter is usually set initially using the Tuning utility in the PMAC Executive Program. It may be
changed on the fly at any time to create types of adaptive control.
changed on the fly at any time to create types of adaptive control.
Ixx33 is not used if Iyy00/50 for the motor has been set to 1 to enable the Extended Servo Algorithm
(ESA) for the motor.
(ESA) for the motor.