Mitsubishi Electric MR-J4, Instruction Manual

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12. ABSOLUTE POSITION DETECTION SYSTEM
12 - 1
12. ABSOLUTE POSITION DETECTION SYSTEM
CAUTION
If [AL. 25 Absolute position erased] or [AL. E3 Absolute position counter warning]
has occurred, always perform home position setting again. Otherwise, it may
cause an unexpected operation.
If [AL. 25], [AL. 92], or [AL. 9F] occurs due to such as short circuit of the battery,
the MR-BAT6V1 battery can become hot. Use the MR-BAT6V1 battery with case
to prevent getting burnt.
POINT
Refer to section 11.8 for the replacement procedure of the battery.
There are four types of batteries, MR-BAT6V1SET, MR-BAT6V1BJ, MR-
BAT6V1SET-A and MR-BT6VCASE available to construct the absolute position
detection system. MR-BAT6V1BJ has the following advantages compared to
other batteries.
You can disconnect the encoder cable from the servo amplifier.
You can replace the battery with the control circuit power supply off.
When absolute position data is erased from the encoder, always execute home
position setting before operation. The absolute position data of the encoder will
be erased in the followings. Additionally, when the battery is used out of
specification, the absolute position data can be erased.
MR-BAT6V1SET , MR-BAT6V1SET-A and MR-BT6VCASE
The encoder cable was disconnected.
The battery was replaced when the control circuit power supply was off.
MR-BAT6V1BJ
A connector or cable was disconnected between the servo motor and battery.
The battery was replaced with procedures other than those of (6) in section
11.8.3.
12.1 Summary
12.1.1 Features
For normal operation, 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 programmable 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.
Even at a power failure or a malfunction, the system can be easily restored.