ABB ACS880 ESP, Руководство по прошивке

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66 Standard programposi features

Position counter
The control program contains a position counter feature that can be used to indicate
the position of a load, eg. the position of a conveyor belt or the height of the load on a
crane. The output of the counter function, parameter
90.07 Load position scaled int ,
indicates the scaled number of revolutions read from an encoder through either
encoder interface. A position estimate calculated internally by the motor control can
be used instead of encoder feedback. (The estimate is also used until next stop if the
selected feedback is lost and its monitoring parameter is set to warning instead of
fault.)
The source of the measurement is selected by 90.51 Load feedback selection . Any
gear ratio between the encoder and load is defined by 90.53 Load gear numerator
and 90.54 Load gear denominator . In case the internal position estimate is chosen as
the source, the gear between the motor and load must be defined in 90.61 Gear
numerator and 90.62 Gear denominator .
The relation between revolutions of the motor shaft and the translatory movement of
the load (in any given unit of distance) is defined by parameters
90.63 Feed constant
numerator and 90.64 Feed constant denominator .
By default, all of the ratios mentioned above are 1:1.
M
X
Y
e
X
Y
X
Y
X
Y
X
Y
e
e
e
Position
initialization
Encoder 1
Load
Encoder 2
Encoder 1
Encoder 2
90.43 90.53
90.44
90.54
90.62
90.61
90.63
90.64
Position estimate
90.07
90.58