Alarm 4312: Encoder battery error
On an English-language pendant this is displayed as "ENCODER BATTERY ERROR".
Type: minor alarm · Condition: the voltage of the encoder backup battery has dropped below 2.8 V
Why it should be handled early
Even while the controller is switched off, the absolute encoders keep their position data using power from the battery unit on the manipulator. If the battery runs out, the encoder memory is cleared, an "encoder backup error" occurs, and the home position has to be recovered. Alarm 4312 is the warning that comes before that. Deal with it before any long shutdown or power-off.
Causes and remedies
| Cause | Remedy |
|---|---|
| Battery exhausted | Replace the battery unit |
| Poor connection | Reset the alarm and check the manipulator cable connectors |
| Encoder (motor) failure | If the alarm returns even with a new battery, replace the motor |
Key point when replacing
The most important point is to connect the new battery before disconnecting the old one, so that power to the encoders is never interrupted. For the procedure, see Replacing the encoder battery unit.
If the position data is lost anyway
Even if an "encoder backup error" has occurred, you may be able to recover with the pendant's encoder backup error recovery function ("backup alarm recovery"), provided the motor and encoder have not been replaced. For details, see Home position calibration.
An alarm that is easily confused
- Alarm 0790 (MEMORY BATTERY WEAK) – a warning for the CMOS memory battery on the robot I/F board (AIF01) inside the controller. It is a different battery from the encoder battery. See YRC1000 memory battery replacement.
Source: Based on YASKAWA manuals RE-CER-A600 and HW1484423.