Technosoft iPOS4808 BX-CAN, Technical Reference

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Technosoft 2015 88 iPOS4808 BX-CAN Technical Reference
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
For linear motors:
Pole_Pitch
Load_Speed[SI] = ×Motor_Speed[IU]
resolution× Tr × T
where:
resolution – is the motor position resolution
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”
Pole_Pitch – is the magnetic pole pitch NN (distance expressed in [m])
6.2.3. DC brushed motor with quadrature encoder on load and tacho on motor
The internal speed units are encoder counts / (slow loop sampling period). The motor is rotary and
the transmission is rotary-to-rotary. The correspondence with the load speed in SI units is:
] IU [ Speed _ Load
T lines _ encoder _ No
] SI [ Speed _ Load
×
× ×
π ×
=
4
2
where:
No_encoder_lines – is the 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”
6.2.4. DC brushed motor with tacho on motor
When only a tachometer is mounted on the motor shaft, the internal speed units are A/D converter
bits. The correspondence with the load
speed in SI units
1
is:
] IU [ Speed _ Motor
Tr gain _ Tacho
Range _ Input _ ue log Ana
] SI [ Speed _ Load
×
× ×
=
4096
1
SI units for speed are [rad/s] for a rotary movement, [m/s] for a linear movement