Technosoft PIM2401, Technical Reference

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Technosoft 2007 65 PIM2401 Technical Reference
6.1.5. Stepper motor open-loop control. Incremental encoder on load
The internal position units are load encoder counts. The transmission is rotary-to-rotary. The
correspondence with the load position in SI units is:
] IU [ Position _ Load
lines _ encoder _ No
] SI [ Position _ Load
×
×
π ×
=
4
2
where:
No_encoder_lines – is the rotary encoder number of lines per revolution
Tr – transmission ratio between the motor displacement in SI units and load displacement in SI
units
6.2. Speed units
The internal speed units are internal position units / (slow loop sampling period) i.e. the position
variation over one slow loop sampling period
6.2.1. Brushless / DC brushed motor with quadrature encoder on motor
The internal speed units are encoder counts / (slow loop sampling period). The correspondence
with the load
speed in SI units
is:
] IU [ Speed _ Motor
T Tr lines _ encoder _ No
] SI [ Speed _ Load
×
× × ×
π ×
=
4
2
where:
No_encoder_lines – is the rotary 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”
6.2.2. Brushless motor with linear Hall signals
The internal speed units are counts / (slow loop sampling period). The motor is rotary. The
position resolution i.e. number of counts per revolution is programmable as a power of 2 between
512 and 8192. By default it is set at 2048 counts per turn. The correspondence with the load
speed in SI units is:
For rotary motors: ] IU [ Speed _ Motor
T Tr resolution
] SI [ Speed _ Load
×
× ×
π ×
=
2