YASKAWA CR700, Technical Manual, Page: 32 / 886

2.1 Section Safety
32 YASKAWA SIEPC71061723A YASKAWA AC Drive CR700 Technical Manual
NOTICE
Select a motor that is compatible with the load torque and speed range. When 100% continuous
torque is necessary at low speed, use an inverter-duty motor or vector-duty motor. When you
use a standard fan-cooled motor, decrease the motor torque in the low-speed range.
If you operate a standard fan-cooled motor at low speed and high torque, it will decrease the cooling effects and
can cause heat damage.
Obey the speed range specification of the motor as specified by the manufacturer. When you
must operate the motor outside of its specifications, contact the motor manufacturer.
If you continuously operate oil-lubricated motors outside of the manufacturer specifications, it can cause damage
to the motor bearings.
When the input voltage is 440 V or higher or the wiring distance is longer than 100 m (328 ft),
make sure that the motor insulation voltage is sufficient or use an inverter-duty motor or vector-
duty motor with reinforced insulation.
Motor winding and insulation failure can occur.
Install vibration-proof rubber on the base of the motor or use the frequency jump function in the
drive to prevent specific frequencies that vibrate the motor.
Motor or system resonant vibration can occur in fixed speed machines that are converted to variable speed. Too
much vibration can cause damage to equipment.
The motor may require more acceleration torque with drive operation than with a commercial
power supply. Check the load torque characteristics of the machine to be used with the motor.
You can use the drive with an explosion-proof motor, but the drive is not explosion-proof. Install
the drive only in the environment shown on the nameplate.
If you install the drive in a dangerous environment, it can cause damage to the drive.
Do not lift the drive with the covers removed.
If the drive does not have covers, you can easily cause damage to the internal parts of the drive.
Do not use unshielded wire for control wiring. Use shielded, twisted-pair wires and ground the
shield to the ground terminal of the drive.
Unshielded wire can cause electrical interference and unsatisfactory system performance.
Before you connect a dynamic braking option to the drive, make sure that qualified personnel
read and obey the Braking Unit and Braking Resistor Unit Installation Manual
(TOBPC72060001).
If you do not read and obey the manual or if personnel are not qualified, it can cause damage to the drive and
braking circuit.
Make sure that all connections are correct after you install the drive and connect peripheral
devices.
Incorrect connections can cause damage to the drive.