Position & mastering
Robot needs re-mastering after every power cycle
If the robot loses position and demands mastering after every power cycle, the encoders aren't holding absolute position data across power-off.
Most likely causes
Backup battery for the encoder absolute position is empty, missing, or its cable is disconnected or grounded
The battery in the robot base battery box backs up absolute position data. If it is empty, removed, or the internal cable feeding power from the battery to the Pulsecoder is disconnected or grounded, the position data can be lost, so mastering is required again. If BZAL appears right after a fresh battery install, the internal battery cable is the suspect.
Recovery sequence left incomplete, so SRVO-075 was never cleared before mastering
After BZAL recovery, SRVO-075 'Pulse not established' appears on the next power-up. It must be cleared (jog the named axis about one motor revolution until it stops recurring) before mastering. This is the step people skip, then wonder why mastering won't take.
Rotation counter miscounting, which can be a grounding/noise story or a failing pulse coder
SRVO-063 (RCAL) means the encoder's built-in rotation counter is abnormal, leaving position bookkeeping suspect. When it appears alongside SRVO-068/069/070, work those communication alarms instead.
Where to start
- Read the active and history alarms and identify which encoder/position code family you're in: SRVO-062 (BZAL), SRVO-063 (RCAL), or SRVO-075.
- If SRVO-062 is present, check the robot base backup battery and, if BZAL returned after a new battery, the internal battery-to-Pulsecoder cable.
- If SRVO-075 keeps appearing, it must be cleared before mastering will hold.
- If SRVO-063 shows up with SRVO-068/069/070, work those communication alarms first.
- Open the matching alarm-code page and hand off to qualified maintenance.
Related alarm codes
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