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7.2.3. 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:
Load _ Speed[SI] =
2× π
× Load _ Speed[IU]
4 × No _ encoder _ lines × T
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”
7.2.4. DC brushed motor with absolute SSI 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:
Load _ Speed[SI] =
2× π
2No _ bits _ resolution × T
× Load _ Speed[IU]
where:
No_bits_resolution – is the SSI encoder resolution in bits 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”
7.2.5. 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:
Load _ Speed[SI] =
Ana log ue _ Input _ Range
× Motor _ Speed[IU]
4096 × Tacho _ gain × Tr
where:
Analogue_Input_Range – is the range of the drive analogue input for feedback, expressed in [V].
You can read this value in the “Drive Info” dialogue, which can be opened from the “Drive Setup”
Tacho_gain – is the tachometer gain expressed in [V/rad/s]
1
SI units for speed are [rad/s] for a rotary movement, [m/s] for a linear movement
© Technosoft 2008
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TMC3D Technical Reference