B-65285EN/03 TROUBLESHOOTING 3.TROUBLESHOOTING AND ACTION
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3.4.23 Alarm Code 47
The count value of α position coder signal pulses is abnormal.
Phases A and B for the position coder have a feedback pulse count of
4096 p/rev per spindle rotation. The SPM checks the pulse counts of
phases A and B equivalent to the position coder each time a one-
rotation signal is generated. The alarm is issued when a pulse count
beyond the specified range is detected.
(1) If this alarm is issued when the cable is moved (as in the case
where the spindle moves)
The conductor may be broken. Replace the cable. If coolant has
penetrated into the connector, clean the connector.
(2) Troubleshooting in other cases
(a) The setting of a parameter is incorrect.
Referring to "FANUC AC SPINDLE MOTOR αi series
Parameter Manual (B-65280EN)," check the parameter for
(b) The shielding of the cable between the sensor and SPM is
Referring to "Connection," in "FANUC SERVO
AMPLIFIER αi series Descriptions (B-65282EN)," check
the shielding of the cable.
(c) The signal cable is bundled with the servo motor power lead.
If the cable between the sensor and SPM is bundled with the
servo motor power lead, separate them from each other.
(d) The SPM is faulty.
Replace the SPM or SPM control printed circuit board.
3.4.24 Alarm Code 50
A value obtained by internal calculation in spindle synchronization
exceeded the allowable range.
Troubleshooting when this alarm is issued
(a) The setting of parameters for gear ratio setting is incorrect.
Check if an excessively large gear ratio is set.
(b) Position gain setting limit
If correct gear ratio data is set, increase the position gain value in
3056 to 3059 4056 to 4059 Gear ratio between the spindle and motor
3065 to 3068 4065 to 4068
Position gain in the servo mode/spindle
Connected to the frame
ground via a cable clamp.