GENERAL
Introduction
AC spindle drive unit, FR-SFJ series, is the inverter use,?
to control a machine tool spindle drive AC motor.
It is capable of
widely ranged motor speeds ac-
curately and quietly.
Discharge resistors are
the drive unit to disperse regenerative energy for regenera-
tive braking of motor.
This manual mainly describes periodic maintenance and trou-
bleshooting which are very important to assure successful
use of your AC spindle
1.2
Safety during
and troubleshooting
The maintenance and troubleshooting should be done with
the
following safety consideration:
o The control system should be maintained and remedied by
qualified electrician.
o When a person who maintains or remedy the control system
must touch a part of control system under live condition,
he should take off finger ring, wristwatch, necktie pin,
and other metallic goods before starting the work.
o Electric shock may cause fatal accident.
When a circuit at high voltage must be checked, due care
should be taken to select appropriate test/inspection
equipment, tools, etc.
and to use them safetly (no matter
whether or not the circuit is grounded).
When a test equipment is applied to a part, component, or
circuit of the unit,
operator should pay attention not to
touch a grounded part.
In general,
test equipment should not be grounded.
During test or measurement,
it is likely that high voltage
is present across the test equipment and the ground.
When motor is run during adjustment or remedy, due care
should be taken in this respect.
o Person who carries out maintenance or remedy of rotative
machinery should not wear loosely (otherwise loose wear
