YASKAWA GA700 Technical Manual page 28

2.1 Safety Precautions
Reduce the motor torque in the low-speed range whenever using a standard blower cooled
motor. If 100% torque is required continuously at low speed, consider using a special drive or
vector-control motor. Select a motor that is compatible with the required load torque and
operating speed range.
Operating the motor in the low-speed range diminishes the cooling effects, increases motor temperature, and may
lead to motor damage by overheating.
The speed range for continuous operation differs according to the lubrication method and
motor manufacturer. If the motor is to be operated at a speed higher than the rated speed,
consult with the manufacturer.
Continuously operating an oil-lubricated motor in the low-speed range may result in burning.
When the input voltage is 440 V or higher or the wiring distance is greater than 100 meters, pay
special attention to the motor insulation voltage or use a drive-rated motor with reinforced
insulation.
Failure to comply could lead to motor winding failure.
Motor vibration may increase when operating a machine in variable-speed mode, if that machine
previously operated at a constant speed.
Install vibration-proof rubber on the motor base or use the frequency jump function to skip a frequency
resonating the machine.
The motor may require more acceleration torque with drive operation than with a commercial
power supply. Set a proper V/f pattern by checking the load torque characteristics of the
machine to be used with the motor.
The rated input current of submersible motors is higher than the rated input current of standard
motors. Select an appropriate drive according to its rated output current. When the distance
between the motor and drive is long, use a cable thick enough to connect the motor to the drive
to prevent motor torque reduction.
When using an explosion-proof motor, it must be subject to an explosion-proof test in
conjunction with the drive. This is also applicable when an existing explosion-proof motor is to
be operated with the drive. Since the drive itself is not explosion-proof, always install it in a safe
place.
Failure to comply could result in damage to the drive.
Do not the lift drive when it has its cover removed.
The drive board and terminal block may be damaged.
Do not use unshielded wire for control wiring. Use shielded, twisted-pair wires and ground the
shield to the ground terminal of the drive.
Failure to comply could cause electrical interference resulting in poor system performance.
Carefully review instruction manual TOBPC72060001 before connecting a dynamic braking
option to the drive.
Failure to comply could damage the drive or braking circuit.
Do not modify the drive circuitry.
Failure to comply could cause damage to the drive and will void warranty. Yaskawa is not responsible for any
modification of the product made by the user.
Confirm that all connections are correct after installing the drive and connecting peripheral
devices.
Failure to comply could damage the drive.
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NOTICE
YASKAWA ELECTRIC SIEP C710617 01B YASKAWA AC Drive GA700 Technical Manual