Technosoft iPOS4808 BX-CAN, Technical Reference

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Technosoft 2015 98 iPOS4808 BX-CAN Technical Reference
6.9. Master position units
When the master position is sent via a communication channel, the master position units depend
on the type of position sensor present on the master axis.
6.10. Master speed units
The master speed is computed in internal units (IU) as master position units / slow loop sampling
period i.e. the master position variation over one position/speed loop sampling period.
6.11. Motor position units
6.11.1. Brushless / DC brushed motor with quadrature encoder on motor
The internal motor position units are encoder counts. The correspondence with the motor position
in SI units 1 is:
] IU [ Position _ Motor
lines _ encoder _ No
] SI [ Position _ Motor
×
×
π ×
=
4
2
where:
No_encoder_lines – is the rotary encoder number of lines per revolution
6.11.2. Brushless motor with linear Hall signals
The internal motor position units are counts. The motor is rotary. The 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 position in SI units is:
For rotary motors: ] IU [ Position _ Motor
resolution
] SI [ Position _ Motor
×
π ×
=
2
For linear motors:
Pole_Pitch
Motor_Position[SI] = ×Motor_Position[IU]
resolution
where:
resolution – is the motor position resolution
Pole_Pitch – is the magnetic pole pitch NN (distance expressed in [m])
6.11.3. DC brushed motor with quadrature encoder on load and tacho on motor
The motor position is not computed.
1
SI units for motor position are: [rad] for a rotary motor, [m] for a linear motor