Notes On Motor Operation - YASKAWA E1000 Technical Manual

i.2 General Safety
• 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.

◆ 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.
Figure i.2 shows the allowable load characteristics for a Yaskawa standard motor. A motor designed specifically for
operation with a drive should be used when 100% continuous torque is needed at low speeds.
Figure i.2
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.
Vibration and Shock
E1000 lets the user choose between high carrier PWM control and low carrier PWM. Selecting high carrier PWM can
help reduce motor oscillation.
Take particular caution when using a variable speed drive for an application that is conventionally run from line power at
a constant speed. If resonance occurs shock-absorbing rubber should be installed around the base of the motor and the
Jump frequency selection should be enabled to prevent continuous operation in the resonant frequency range.
20
25% ED (or 15 min)
40% ED (or 20 min)
100
90
80
70
60
Torque
(%)
50
YEC_common
3 6
Figure i.2 Allowable Load Characteristics for a Yaskawa Motor
YASKAWA ELECTRIC SIEP C710616 35D YASKAWA AC Drive E1000 Technical Manual
60% ED (or 40 min)
Continuous operation
20 50
Frequency (Hz)