Technosoft iPOS4808 BX-CAN, Technical Reference

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Technosoft 2015 96 iPOS4808 BX-CAN Technical Reference
6.4.6. Step 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
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”.
6.4.7. Brushless motor with sine/cosine encoder on motor
The internal jerk units are interpolated encoder counts / (slow loop sampling period)
3
. The
correspondence with the load jerk in SI units is:
For rotary motors: ] IU [ Jerk _ Motor
T Tr ion Interpolat periods _ Enc
] SI [ Jerk _ Load
×
× × × ×
π ×
=
3
4
2
For linear motors:
] IU [ Jerk _ Motor
T Tr ion Interpolat
accuracy _ Encoder
] SI [ Jerk _ Load
×
× ×
=
3
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”
6.5. Current units
The internal current units refer to the motor phase currents. The correspondence with the motor
currents in [A] is:
] IU [ Current
Ipeak
] A [ Current
×
×
=
65520
2
where Ipeak – is the drive peak current expressed in [A]. You can read this value in the “Drive
Info” dialogue, which can be opened from the “Drive Setup”.