IAI America NS - Manual (Page 54)

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10. Notes on Operation
10.3 About Home Return
10.3.1 Operating Principles of Home Return
This actuator implements a home return in the following steps:
[1] Upon receiving a home return command, the actuator determines the moving direction based on the
specified parameter.
[2] The actuator detects a home sensor signal during the return operation.
[3] After detecting the home sensor signal, the actuator reverses its direction and operates until a phase
Z signal is detected, upon which the actuator defines the applicable position as the reference point.
[4] The actuator travels further by the offset specified by a parameter, and defines the achieved position
as the home.
10.3.2 Fine-tuning the Home Position
The motor revolution after a home sensor signal is detected until a phase Z signal generates has been
adjusted prior to shipment.
The table below shows the standard distances from the stopper, reached by the slider when it reverses its
direction upon detecting a home sensor signal and eventually stops at the home position.
Lead Distance from mechanical stopper (mm)
20 mm or less 5 r 1
Over 20 mm 5 r 2
If the direction of home return remains the same, the home position for each actuator can be fine-tuned
using the applicable distance shown above by changing the parameter. Follow the steps below to fine-
tune the home position:
[1] Perform a home return operation to check the home.
[2] Calculate the difference between the current home position and desired home position, and correct
the parameter accordingly.
The value set in the parameter represents an offset in the positive moving direction of the actuator.
(The position cannot be corrected in the negative direction.)
[3] Increasing the offset will narrow the moving range of the actuator.
If an offset exceeding 1 mm has been set, also adjust the stroke soft limits.
Warning
The encoder not only detects angles of rotation and home signals, but it also serves an important
role in the switching of phases in the AC-servo power line. For this reason, the encoder phases
have been adjusted precisely. Never touch the encoder to change the home.