Technosoft PIM2401, Technical Reference

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Technosoft 2007 72 PIM2401 Technical Reference
6.4.4. Stepper motor open-loop control. No feedback device
The internal jerk units are motor µsteps / (slow loop sampling period)
3
. The correspondence with
the load
jerk in SI units
1
is:
] IU [ Jerk _ Motor
T Tr steps _ No steps _ No
] SI [ Jerk _ Load
×
× × × μ
π ×
=
3
2
where:
No_steps – is the number of motor steps per revolution
No_µsteps – is the number of microsteps per step. You can read/change this value in the “Drive
Setup” dialogue from EasySetUp.
Tr – transmission ratio between the motor displacement in SI units and load displacement in SI
units
T – is the slow loop sampling period expressed in [s]. You can read this value in the “Advanced”
dialogue, which can be opened from the “Drive Setup”
6.4.5. Stepper motor open-loop control. Incremental encoder on load
The internal jerk units are load encoder counts / (slow loop sampling period)
3
. The transmission is
rotary-to-rotary. The correspondence with the load jerk in SI units is:
] IU [ Jerk _ Load
T lines _ encoder _ No
] SI [ Jerk _ Load
×
× ×
π ×
=
3
4
2
where:
No_encoder_lines – is the rotary encoder number of lines per revolution
T – is the slow loop sampling period expressed in [s]. You can read this value in the “Advanced”
dialogue, which can be opened from the “Drive Setup”.
6.4.6. Stepper motor closed-loop control. Incremental encoder on motor
The internal jerk units are motor encoder counts / (slow loop sampling period)
3
. The
correspondence with the load jerk in SI units is:
] IU [ Jerk _ Motor
T Tr lines _ encoder _ No
] SI [ Jerk _ Load
×
× × ×
π ×
=
3
4
2
where:
No_encoder_lines – is the motor encoder number of lines per revolution
Tr – transmission ratio between the motor displacement in SI units and load displacement in SI
units
1
SI units for jerk are [rad/s
3
] for a rotary movement, [m/s
3
] for a linear movement