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12. ABSOLUTE POSITION DETECTION SYSTEM
12. ABSOLUTE POSITION DETECTION SYSTEM
CAUTION
If an absolute position erase alarm (25) or abs olute position counter warning (E3)
has occurred, always perform home position s etting again. Not doing so can cause
runaway. Not doing so may cause unexpected opera tion.
POINT
If the encoder cable is disconnected, absolute position data will be lost in the
following servo motor series. HF-MP, HF-KP, HC-SP, HC-RP, HC-UP, HC-LP,
and HA-LP. After disconnecting the encoder cable, always execute hom e
position setting and then positioning operation.
12.1 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 cou nter designed to detect the number of revolut ions.
The absolute position detection system always det ects the absolute position of the machine and keeps it
battery-backed, independently of whether the servo syst em 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
Current
position
Home position data
LS0
CYC0
Servo amplifier
Position data
Detecting
the number
of revolutions
Detecting the
position within
one revolution
Position control
speed control
High speed serial
communication
Servo motor
1 pulse/rev accumulative revolution counter
Within one-revolution counter
MR-J3BAT
Battery