SRVO-138: SDAL alarm (pulse coder signal error)
Software caught a signal error from the encoder - and the manual offers a genuinely useful diagnostic split: if a power cycle restores normal operation, it was noise; if not, the encoder is dead.
What it means
Software caught a signal error from the encoder - and the manual offers a genuinely useful diagnostic split: if a power cycle restores normal operation, it was noise; if not, the encoder is dead.
Common causes
Ranked by what technicians most often find, most likely first.
- Electrical noise on the encoder line (recoverable by power cycle - improve shielding).
- Failure or disconnection inside the encoder (not recoverable - replace).
How to fix it
- Cycle power. If operation resumes normally, treat it as noise: enhance the encoder cable shielding so it doesn't recur.
- If the alarm survives the power cycle, the encoder is defective: replace the motor and perform mastering.