Mitsubishi FREQROL-SFJ Maintenance Manual page 91

Trouble III
Control equip-
ment fails from
time to time, or
error occurs in
oriented spindle
stop position.
(Condition is
restored when
the power is
turned off and
then on to re-
set.)
Checkup
In this case, the compre-
hensive analysis must be
accomplished to deter-
mine the cause (load con-
dition, operation mode,
etc.).
power failure occurred
or "UNDER VOLTAGE"
was displayed.
occurred in contol
circuit, due
noise.
The control equipment
is capable of with-
standing noise (in
power supply) of 16OOV/
due to momentary
change of load.
Check with particular
care if error occurred
in oriented spindle
stop.
Remedy
(1) Check the power
(2) Determine the
noise source and
to large install a surge
killer, etc.
Check and improve
grounding method
(particularly,
grounding of de-
(3) Check mechanisms
carefully.
Check backlash
between spindle
and spindle en-
coder.