Yaskawa G7 Drive - Manual (Page 405)

7
-24
‹ If the Motor Overheats
Take the following steps if the motor overheats.
„ The load is too big.
If the motor load is too heavy and the motor is used with the effective torque exceeding the motor's rated
torque, the motor will overheat. Some motor rating are given for short period performance and are not contin-
uous ratings. Reduce the load amount by either lightening the load or lengthening the acceleration/decelera-
tion time. Also consider increasing the motor capacity.
„ The ambient temperature is too high.
The motor rating is determined within a particular ambient operating temperature range. The motor will burn
out if it is run continuously at the rated torque in an environment in which the maximum ambient operating
temperature is exceeded. Lower the motor's ambient temperature to within the acceptable ambient operating
temperature range.
„ The withstand voltage between the motor phases is insufficient.
When the motor is connected to the Drive output, a surge is generated between the Drive switching and the
motor coil. Normally the maximum surge voltage is three times the Drive's input power supply voltage. Be
sure to use a motor with a withstand voltage between the motor phases that is greater than the maximum surge
voltage. In particular, when using a 380-380 V class Drive, use a special motor for Drives.
„ Autotuning has not been performed for vector control
Vector control will not perform if autotuning has not been performed. Perform autotuning, or set the motor
parameters through calculations. Alternatively, change the Control Method Selection (A1-02) to V/f control (0
or 1).
‹ If There is Noise When the Drive is Started or From an AM Radio
If noise is generated by Drive switching, implement the following countermeasures:
• Change the Drive's Carrier Frequency Selection (C6-02) to lower the carrier frequency. This will help to
some extent by reducing the amount of internal switching.
• Install an Input Noise Filter at the Drive's power supply input area.
• Install an Output Noise Filter at the Drive's power supply output area.
• Use metal tubing. Electric waves can be shielded by metal, so encase the Drive with metal (steel).
• Ground the Drive and motor.
• Separate main circuit wiring from control wiring.