Mitsubishi Electric MELSERVO-J3W Series Instruction Manual page 471

15. MR-J3W-0303BN6 SERVO AMPLIFIER
15.10 Absolute position detection system
CAUTION
15.10.1 Features
For normal operation, as shown below, the encoder consists of a detector designed to detect a position within
one revolution and a cumulative revolution counter designed to detect the number of revolutions.
The absolute position detection system always detects the absolute position of the machine and keeps it battery-
backed, independently of whether the servo system controller power is on or off. Therefore, once home position
return is made at the time of machine installation, home position return is not needed when power is switched on
thereafter.
If a power failure or a fault occurs, restoration is easy.
Servo system controller
If Absolute position erased (25.1) or Absolute position counter warning (E3. ) has
occurred, always perform home position setting again. Otherwise, it may cause an
unexpected operation.
POINT
For HG-AK series servo motors, if the encoder cable is disconnected, absolute
position data will be erased. After disconnecting the encoder cable, always execute
home position setting and then positioning operation.
This section does not include the following items. For details of the items, refer to
each section of the detailed description field.
Confirmation of absolute position data
Current
Home position
LS0
CYC0
Servo motor
1 pulse/rev accumulative revolution
Item
Servo amplifier
Position data
MR-J3BAT
Battery
counter
Within one-revolution counter
15 - 66
Detailed
explanation
Section 12.4
LS
CYC
Detecting the
Detecting the
number of
position within
revolutions
one revolution
High speed
serial
communication