MITSUBISHI ELECTRIC Mitsubishi Programmable Logic Controller QD75D - Manual (Page 588)

14 - 6
MELSEC-Q
14 DEDICATED INSTRUCTIONS
(4) Using the ABRST instruction, 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, ABS 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 completed abnormally, the error complete signal
((D)+1) is turned ON, and the error code is stored 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 turned 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 restoration 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 simultaneously for the
same axis.
(Can be executed simultaneously for different axes.)
• Positioning start instructions (PSTRT1 to PSTRT4)
• Absolute position restoration instructions (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 when 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 Corresponding MELSECNET/H
Network System Reference Manual (Remote I/O Network).