Yaskawa MP940 Reference Manual - Manual (Page 389)

Troubleshooting MotionSuite™ MP940 Machine Controller Reference Manual
10-36
A.F1
A.F1 is the power line open phase alarm display. The alarm output appears
below.
Note: The indicates the output transistor is ON; the x indicates the output transistor is OFF
(alarm state).
Status when Alarm Occurred
Note: Alarm A and B displays occur only in servo amplifiers of 500W or greater.
Alarm Output
Alarm Code Output ALM Output
ALO1 ALO2 ALO3
x x x
Cause Remedy
A One phase (L1, L2, L3) of the
main circuit power supply is dis-
connected. Check power supply.
Check wiring of the main circuit power supply.
Check MCCB, noise filter, magnetic contactor.
B One phase line has low voltage. Check power supply.
C Servo amplifier defective. Replace servo amplifier.
Alarm occurs at brake power
only ON
C
Alarm occurs at main power
ON
A, B