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FANUC Controller
Servo/Axis · Intermediate · 5-30 minutes
Fanuc 484 - Fssb motor mismatch
FSSB 484 alarm indicates a mismatch between the motor configuration data stored in the CNC parameters and the actual motor connected to the servo amplifier. This typically occurs after motor replacement, incorrect parameter settings, or when servo amplifier serial data doesn't match the physical motor installed.
484
Fanuc 484 - Fssb motor mismatch
FSSB MOTOR MISMATCH
An FSSB (Fanuc Serial Servo Bus) error has been detected related to fssb motor mismatch. The serial bus communication between the CNC and servo amplifiers is affected.
Root Cause Summary
FSSB 484 alarm indicates a mismatch between the motor configuration data stored in the CNC parameters and the actual motor connected to the servo amplifier. This typically occurs after motor replacement, incorrect parameter settings, or when servo amplifier serial data doesn't match the physical motor installed.
Safety
- Verify corrected program or parameters before resuming machining
Causes and Fixes
- 1
Verify the motor model number on the physical nameplate matches the motor specified in parameter 1020 (motor type) for the affected axis.
- 2
Access maintenance mode and navigate to the servo parameter screen to check the motor serial number stored in parameters against the actual motor serial number on the nameplate.
Document original parameters before making changes.
- 3
Use the 'Motor ID Write' function in the servo setup menu to register the new motor's serial number and configuration data from the motor to the amplifier.
Ensure correct axis is selected before writing motor ID data.
- 4
After updating motor ID, cycle power completely, then perform servo tuning and verify proper operation through manual axis movement.
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