SRVO-072: PMAL alarm (pulse coder fault)
The controller suspects the encoder itself has failed.
What it means
The controller suspects the encoder itself has failed. Short list, expensive answer: on these motors the encoder isn't separately serviceable in the field, so the fix is encoder/motor replacement - unless it's a phantom riding on a communication alarm.
Common causes
Ranked by what technicians most often find, most likely first.
- Phantom alongside SRVO-068 DTERR / 069 CRCERR / 070 STBERR - if those are in the history, they're the real fault.
- Genuine pulse coder failure.
How to fix it
- Check the alarm history for the 068/069/070 communication trio first; if present, work those remedies before condemning hardware.
- Otherwise replace the pulse coder (motor), then perform mastering. Power-cycle to clear.
Quick facts
- Category
- Servo
- Affected series
- R-30iB; R-30iB Mate; R-30iB Plus; R-30iB Mate Plus
- Alarm family
- SRVO
Related codes
- SRVO-068DTERR alarm (pulse coder no response)
- SRVO-071SPHAL alarm (feedback speed excess)
- SRVO-073CMAL alarm (pulse coder noise/fault)
- SRVO-070STBERR alarm (pulse coder framing error)
- SRVO-074LDAL alarm (pulse coder LED broken)
- SRVO-069CRCERR alarm (pulse coder data corrupt)
- SRVO-076Tip Stick Detection
- SRVO-067OHAL2 alarm (pulse coder overheat)