Technosoft IPS110, Technical Reference

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Technosoft 2007 57 IPS110 Technical Reference
6. Scaling Factors
Technosoft drives work with parameters and variables represented in the drive internal units (IU).
These correspond to various signal types: position, speed, current, voltage, etc. Each type of
signal has its own internal representation in IU and a specific scaling factor. This chapter presents
the drive internal units and their relation with the international standard units (SI).
In order to easily identify them, each internal unit has been named after its associated signal. For
example the
position units
are the internal units for position, the
speed units
are the internal
units for speed, etc.
6.1. Position units
6.1.1. DC brushed motor with quadrature encoder on motor
The internal position units are encoder counts. The correspondence with the load
position in SI
units
20
is:
] IU [ Position _ Motor
Tr lines _ encoder _ No
] SI [ Position _ Load
×
× ×
π ×
=
4
2
where:
No_encoder_lines – is the encoder number of lines per revolution
6.1.2. Stepper motor open-loop control. No feedback device
The internal position units are motor µsteps. The correspondence with the load
position in SI
units
is:
] IU [ Position _ Motor
Tr steps _ No steps _ No
] SI [ Position _ Load
×
× × μ
π ×
=
2
where:
No_steps – is the number of motor steps per revolution
No_µsteps – is the number of microsteps per step. You can read/change this value in the
“Drive Setup” dialogue from EasySetUp.
Tr – transmission ratio between the motor displacement in SI units and load displacement
in SI units
20
SI units for position are: [rad] for a rotary movement, [m] for a linear movement