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Technosoft 2018
79
iPOS4808 VX Technical Reference
]
IU
[
Speed
_
Motor
T
steps
_
No
steps
_
No
]
SI
[
Speed
_
Motor
×
×
×
µ
π
×
=
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.
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”
Step motor closed-loop control. Incremental encoder on motor
The internal motor speed units are motor encoder counts / (slow loop sampling period). The
correspondence with the load speed in SI units is:
]
IU
[
Speed
_
Motor
T
lines
_
encoder
_
No
]
SI
[
Speed
_
Motor
×
×
×
π
×
=
4
2
where:
No_encoder_lines – is the motor 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”.
Brushless motor with sine/cosine encoder on motor
The internal motor speed units are interpolated encoder counts / (slow loop sampling period). The
correspondence with the motor speed in SI units is:
For rotary motors:
]
IU
[
Speed
_
Motor
T
ion
Interpolat
periods
_
Enc
]
SI
[
Speed
_
Motor
×
×
×
×
π
×
=
4
2
For linear motors:
]
IU
[
Speed
_
Motor
T
ion
Interpolat
accuracy
_
Encoder
]
SI
[
Speed
_
Motor
×
×
=
where:
Enc_periods – is the rotary encoder number of sine/cosine periods or lines per revolution
Encoder_accuracy – is the linear encoder accuracy in [m] for one sine/cosine period
Interpolation – is the interpolation level inside an encoder period. Its a number power of 2
between 1 an 256. 1 means no interpolation
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”