Notes On Motor Operation - YASKAWA T1000V Technical Manual

Magnetic Contactor Installation
Use a magnetic contactor (MC) to ensure that power to the drive can be completely shut off when necessary. The MC
should be wired so that it opens when a fault output terminal is triggered.
Avoid switching a magnetic contactor on the power supply side more frequently than once every 30 minutes. Frequent
switching can cause damage to the drive.
Inspection and Maintenance
Capacitors in the drive take time to discharge even after the power has been shut off. After shutting off the power, wait
for at least the amount of time specified on the drive before touching any components.
The heatsink can become quite hot during operation, and proper precautions should be taken to prevent burns. When
replacing the cooling fan, shut off the power and wait at least 15 minutes to be sure that the heatsink has cooled down.
Even when the power has been shut off for a drive running a PM motor, voltage continues to be generated at the motor
terminals while the motor coasts to stop. Take the precautions described below to prevent shock and injury:
• Applications where the machine can still rotate even though the drive has fully stopped should have a load switch
installed to the output side of the drive.
• Do not allow an external force to rotate the motor beyond the maximum allowable speed, also when the drive has been
shut off.
• Wait for at least the time specified on the warning label after opening the load switch on the output side before
inspecting the drive or performing any maintenance.
• Do not open and close the load switch while the motor is running, as this can damage the drive.
• If the motor is coasting, make sure the power to the drive is turned on and the drive output has completely stopped
before closing the load switch.
Wiring
All wire ends should use ring terminals for UL/cUL compliance. Use only the tools recommended by the terminal
manufacturer for crimping.
Transporting the Drive
Never steam clean the drive.
During transport, keep the drive from coming into contact with salts, fluorine, bromine, phthalate ester, and other such
harmful chemicals.

◆ Notes on Motor Operation

■ Using a Standard Motor
Low Speed Range
The cooling fan of a standard motor is usually designed to sufficiently cool the motor at the rated speed. As the self-
cooling capability of such a motor reduces with the speed, applying full torque at low speed will possibly damage the
motor. To prevent motor damage from overheat, reduce the load torque as the motor slows.
Insulation Tolerance
Consider voltage tolerance levels and insulation in applications with an input voltage of over 440 V or particularly long
wiring distances. Contact Yaskawa or your Yaskawa agent for consultation.
High Speed Operation
Problems may occur with the motor bearings and dynamic balance of the machine when operating a motor beyond its
rated speed. Contact the motor or machine manufacturer.
Torque Characteristics
Torque characteristics differ compared to operating the motor directly from line power. The user should have a full
understanding of the load torque characteristics for the application.
YASKAWA ELECTRIC SIEP C710606 44B YASKAWA AC Drive T1000V Technical Manual
i.2 General Safety
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