
3. TROUBLESHOOTING
B-65165E/02 TROUBLESHOOTING AND ACTION
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3.4.1.17 Alarm code 27
The sensor signal (position coder signal) for position control is
abnormal.
<1> The signal of the α position coder is disconnected (for all types).
<2> When an MZ or BZ sensor is used with SPM TYPE1 (using the
JY2 connector), the amplitude of the sensor signal is excessively
small.
<3> When a separate built-in sensor is used with SPM TYPE2 (using
the JY2 and JY5 connectors), the amplitude of the spindle sensor
signal on the JY2 side is excessively small.
<4> When a high-resolution magnetic pulse coder is used with SPM
TYPE2 (using the JY2 and JY5 connectors), the amplitude of the
sensor signal on the low-resolution side (128 to 384 λ) on the JY5
side is excessively small.
<5> When SPM TYPE4 is used, the amplitude of the spindle sensor
signal connected to JY5 is excessively small.
(1) If this alarm is issued when the motor is deactivated
(a) The setting of a parameter is incorrect.
Referring to Chapter 2 of "FANUC AC SPINDLE MOTOR
α series Parameter Manual (B-65160E)," check the
parameter for sensor setting.
(b) The cable connected to JY4 is disconnected. (α position
coder)
When the α position coder is used, adjustment is impossible.
Replace the cable.
(c) The sensor is not adjusted correctly.
Adjust the sensor signal according to Subsection 4.3.4 of
Part I of this manual. If the sensor signal cannot be adjusted
correctly, or the sensor signal is not observed, replace the
connection cable and sensor.
(d) The SPM is faulty.
Replace the SPM or SPM control printed circuit board.
(2) If this alarm is issued when the cable is moved (as in the case
where the spindle moves)
(a) The connector has a bad contact, or the cable is
disconnected.
The conductor may be broken. Replace the cable. If coolant
has penetrated into the connector, clean the connector.
S
P
M
Sensor
Connected to the frame
ground via a cable clamp.
Shielded cable
α position coder