14 - 6
MELSEC-Q
14 DEDICATED INSTRUCTIONS
(4) Using the ABRST ins truction, the absolute position restoration is carried out in
the following procedure.
End
Output the ((S)+3) data.
Is ((S)+4) "0"?
Other than "0"
0
Set the ABS data bit 0/bit 1 and transmission data READY flag
using the sequence program.
Output the servo ON, AB S transfer mode, and ABS request flag
to the output module using the sequence program.
Start
. . . . . . . . .
. . . . . . . . .
Execute the ABRST instruction.
Set the data in ((S)+2).
[Errors] (1) When a dedicated instruction is com pleted abnormally, the error complete signa l
((D)+1) is turned ON, and the error code is st ored in the complete status ((S)+1).
Check and take a measure against the error referring to Section 15.2 "List of error
codes".
[Precautions] (1) After the absolute position detection system is configured, the absolute position
restoration must be carried out at least once after the power is turned ON or reset.
Unless the absolute position restoration of the QD75 is completed, the servo
amplifier will not be turned ON.
(2) Execute absolute position restoration when the PLC READY signal [Y0] is OFF.
(3) The restoration of the absolute position ( ABRST instruction execution) can also
be carried out when the servo amplifier is tur ned ON. If this is carried out,
however, the servo ON signal is turned OFF for about 20 ms (servo OFF) and the
motor may move.
When carrying out the absolute position restora tion during servo OFF, install an
electromagnetic brake and output the ABRST instruction to that brake during the
ABRST instruction execution.
(4) The following dedicated instructions cannot be executed simul tane ou sly fo r the
same axis.
(Can be executed simultaneously for different ax es.)
• Positioning start instructions (PSTRT1 to P STRT4)
• Absolute position restoration instruct ions (ABRST1 to ABRST4)
• Teaching instructions (TEACH1 to TEACH4)
(5) When the remote I/O station (Q Corresponding MELSECNET /H network remote
I/O module) is used, the dedicated instruction (ABRST ) is unusable.
(For the sequence program example for use whe n the dedicated instruction is not
used, refer to the Mitsubishi General-Purpose AC Servo "Absolute Position
Detection System" Installation Guide.)
: For details of the remote I/O station, refer to Q C orresponding MELSECNET/H
Network System Reference Manual (Remote I/O Network ).