Delta ASDA-A3 Series User Manual page 747

Troubleshooting
There are four types of alarms: General, STO, Communication, and Motion control.
See detailed information below:
General type: alarms caused by hardware or encoder signal errors.
13
STO type: alarms caused by STO errors.
Communication type: alarms caused by CANopen or DMCNET errors.
Motion control type: alarms caused by motion control command (in PR mode) errors.
AL.nnn is the alarm format on the 7-segment display.
13-2
ASDA-A3