Technosoft iPOS4808 BX-CAN, Technical Reference

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Technosoft 2015 100 iPOS4808 BX-CAN Technical Reference
6.12. Motor speed units
6.12.1. Brushless / DC brushed motor with quadrature encoder on motor
The internal motor speed units are encoder counts / (slow loop sampling period). The
correspondence with the motor
speed in SI units is:
For rotary motors: ] IU [ Speed _ Motor
T lines _ encoder _ No
] SI [ Speed _ Motor
×
× ×
π ×
=
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”
6.12.2. Brushless motor with linear Hall signals
The internal motor 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 motor
speed in SI units is:
For rotary motors: ] IU [ Speed _ Motor
T resolution
] SI [ Speed _ Motor
×
×
π ×
=
2
For linear motors:
Pole_Pitch
Motor_Speed[SI] = ×Motor_Speed[IU]
resolution× T
where:
resolution – is the motor position resolution
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”
Pole_Pitch – is the magnetic pole pitch NN (distance expressed in [m])
6.12.3. DC brushed motor with quadrature encoder on load and tacho on motor
The internal motor speed units are A/D converter bits. The correspondence with the motor speed
in SI units 1 is:
] IU [ Speed _ Motor
gain _ Tacho
Range _ Input _ ue log Ana
] SI [ Speed _ Motor
×
×
=
4096
where:
1
SI units for motor speed are [rad/s] for a rotary motor, [m/s] for a linear motor