Delta ASDA-A3 Series User Manual page 395

Operation Mode
◼
Error clearing disabled (P1.084.X = 1)
6
Stage 1: full-closed loop control (feedback position of the auxiliary encoder)
If the servo drive issued a position command of 10,000 PUU and the feedback position of the
auxiliary encoder is 10,000 PUU, the final feedback position of the motor encoder is 11,000 PUU
due to the backlash and sliding of the mechanical parts.
Stage 2: semi-closed loop control (feedback position of the motor encoder)
Use DI [0x0B] to switch the control mode from full-closed loop to semi-closed loop, and then
issue the position command of 10,000 PUU again. In semi-closed loop control, since the
command refers to the position of the motor encoder, the feedback position of the motor
encoder is 21,000 PUU, but the feedback position of the auxiliary encoder is 19,000 PUU.
In this mode, there is an error of 1,000 PUU between the auxiliary encoder (19,000 PUU) and
the position command (20,000 PUU).
Stage 3: full-closed loop control (feedback position of the auxiliary encoder)
When you set P1.084 to 1, the error will not be cleared. Thus, after using DI [0x0B] to switch the
control mode from semi-closed loop to full-closed loop, the feedback position of the auxiliary
encoder is corrected and the motor moves to the corresponding position (yellow area as shown
in the above figure). The previous semi-closed loop command becomes the full-closed loop
command and refers to the auxiliary encoder to move the mechanical part to the position
corresponding to the actual command. The final feedback position of the auxiliary encoder is
20,000 PUU.
6-54
Diagram of error clearing when the system switches
between full- and semi-closed loop modes
Feedback
position
22000
21000
20000
19000
11000
10000
Full-closed loop
(Stage 1)
P1.084.X = 1
After the system
switches from the
semi-closed loop to
full-closed loop mode,
the error is not cleared
and the position moves.
Semi-closed loop Full-closed loop
(Stage 2) (Stage 3)
Auxiliary encoder
Motor encoder
Control mode
ASDA-A3