Yaskawa Sigma Mini - Manual (Page 230)

INSPECTION AND MAINTENANCE
5.2.1 Troubleshooting Problems with Alarm Display
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11.A.C3
Display and Outputs
Digital Operator Display Alarm Name Alarm Output
A.C3 Encoder phase-A, -B
discontinuity
Output transistor is OFF
(alarm state)
Status when Alarm Occurred
D
At power ON
Parameter
Cn-01 bit 0 = 0
When servo ON (/S-ON)
signal turned ON
A
, B, C, D
During Servomotor
operation
A, B, C, D
A , B, C
1 to 3 seconds after
power ON
Parameter
Cn-01 bit 0 = 1
Cause Remedy
A Encoder wiring incorrect or poor
connection.
Check wiring and connectors at encoder.
B Noise in encoder wiring. Separate encoder wiring from main wiring
circuits.
C Encoder defective. Replace Servomotor.
D Circuit board (1PWB) defective. Replace Servopack.
12.A.C4
Display and Outputs
Digital Operator Display Alarm Name Alarm Output
A.C4 Encoder phase-C discontinuity Output transistor is OFF
(alarm state)
Status when Alarm Occurred
C
At power ON
Parameter
Cn-01 bit 0 = 0
When servo ON (/S-ON)
signal turned ON
A
, B, C, D
During Servomotor
operation
A, B, C, D
A , B, C, D
1 to 3 seconds after pow-
er ON
Parameter
Cn-01 bit 0 = 1
5