Yaskawa YASNAC PC NC Maintenance Manual - Manual (Page 174)

The VS-626M5 PC NC Maintenance Manual
4-153
Excessive speed
deviation Speed falls to less than 50%
of reference value. Check that the load is heavy or
a tool is jammed.
Check whether external torque
limit signals TLL and TLH are
input.
Check the control constants.
Check the wiring of encoder sig-
nal lines. _œ_œ_›_›
Load fault Inverter output (U/T1, V/T2,
W/T3) was disconnected. Check inverter output wiring. _œ_œ_›_›
Motor overheat 1 Motor temperature exceeded
upper limit (minor fault). Check the wiring.
Check that motor cooling air is
normal with power ON.
Check that the fan is not
clogged with dust or oil.
Check the wiring of motor ther-
mistor signal lines. _œ_›_œ_œ
Motor overheat 2 Motor temperature over upper
limit continued for over one
minute. _œ_›_œ_œ
Motor thermistor
disconnection Motor temperature detection
thermistor was disconnected. Check the motor thermistor sig-
nal wiring.
Check the motor ambient tem-
perature. [Raise the tempera-
ture to above -10
°
C (14
°
F) or
more.]
_œ_›_œ_œ
Heat sink overheat
1 Heat sink temperature
exceeded upper limit (minor
fault). Check the ambient temperature
for effective cooling. _œ_›_œ_œ
Heat sink overheat
2 Heat sink temperature over
upper limit continued for one
minute or longer. _œ_›_œ_œ
Heat sink ther-
mistor disconnec-
tion Thermistor for heat sink tem-
perature detection was dis-
connected.
The ambient temperature is
low
[-20
°
C (-4
°
F) or below].
Replace the unit.
Raise the ambient temperature
to above -20
°
C (-4
°
F).
_œ_›_œ_œ
Control PC board
temperature fault 1 Control PC board temperature
exceeded +80
°
C (176
°
F)
(minor fault).
Check the ambient temperature
for effective cooling. _œ_›_œ_œ
Control PC board
temperature fault 2 Control PC board temperature
exceeded +85
°
C (185
°
F).
_œ_›_œ_œ
Internal cooling
fan fault Inverter internal cooling fan is
stopped. Replace the internal cooling fan. _œ_›_œ_œ
Tune-up
incomplete
(Encoder method
orientation) Orientation command was
input before tuning up (minor
fault). Perform orientation tune-up. _œ_›_›_œ
Table 4.37: Fault Diagnosis and Inverter Corrective Actions (Continued)
Fault Number Name Contents Corrective Action Fault Code