
B–62835EN/01
8. TROUBLESHOOTING
311
Power to the servo converter is not supplied.Power off
ExplanationMeaning
Display
Internal MMC (electro–magnetic contactor) is not
turned on.
NOT READY
Internal MMC is turned on and the motor
becomes ready.
READY
DC voltage for driving main circuit is considerabley
high.
HV
Excessive
voltage alarm
+5V of control power is abnormally low.LV5V
Control power
low alarm
DC voltage for main circuit is extremely low.LVDC
DC link voltage
low alarm
Regenerative discharge energy in short time is
large or regenerative discharge circuit is faulty.
DCSW
Abnormal regen-
erative control cir-
cuit
Average regenerative discharge energy is large or
frequency of acc./dec. is large.
DCOH
Excessive regen-
erative discharge
Lights when thermostat in the servo amplifier func-
tions.
OH
Servo amplifier
overheat
Contacts of electro–magnetic contactor is blown.MCC
Electro magnetic
contactor
Lights when a large current flows through the main
circuit of L axis.
HCL
L axis excess
current
Lights when a large current flows through the main
circuit of M axis.
HCM
M axis excess
current
Lights when a large current flows throught the main
circuit of L axis and M axis.
HCLM
Excess current
NOTE
1st axis is L, 2nd axis is M.
When the electro–magnetic contactor is turned on in the servo amp. or DC
voltage for the main circuit becomes low, this LED is lit.
Causes are;
1) Input voltage is insufficient.
2) Contacts of electro–magnetic contactor in servo amp. is poor.
3) Power circuit in servo amp. is abnormal.
D LED display
D LVDC alarm