Metronix smartServo BL 4000-C Series, Руководство по эксплуатации продукта

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6 Applications
6.1.15 Tab: Special functions
The checkbox Flying referencing activates a function that is similar to a homing run.
Figure 45: "Homing position" window - "Special functions" tab
The "flying referencing" function can be used to avoid accumulating errors in endless
applications. For this purpose, the set and actual position are set to zero on a rising edge
at the digital input SAMPLE (0/1). This function roughly corresponds to a rotary axis
application. However, in this case, the rotary axis is triggered externally.
Configuration of the homing runs
When configuring the homing runs, the following must be taken into consideration:
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If multi-turn encoders are used, a homing run is not required after a reset, as the
absolute position will always be read out of the encoder. When the application is
set up for the first time, a homing run may be useful in order to set the absolute
position to a specific value. In this case, an internal zero offset will be calculated.
It can be stored in the EEPROM of the angle encoder so that it remains active
after every reset. Alternatively, the motor shaft can be turned so that the current
actual position has the desired value before the motor is connected to the driven
component.
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The speed of movement during the homing run should be selected so that the
reference marks can actually be detected by the servo drive. In some cases, very
low speeds are necessary to ensure this.
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The deceleration values should be sufficiently high to ensure that the servo drive
does not exceed the targets excessively when its direction of movement is
reversed.
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When a homing run has been completed without any errors, the drive may not
always be positioned precisely at the zero position. This depends on the selected
method. A known difference with regard to the index pulse will be taken into
consideration if the index pulse is the reference position for the homing run. It is
only after a follow-up positioning run to home position that the drive is physically
located at zero.
Product manual BL 4000-C Page 85 of 298