Extruders ［Molding machines］
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 Notices regarding the use of inverter drives
- Starting torque
Extruders often require large starting torque.
If extruders need over 200% starting torque, the inverter capacity should be larger than the motor capacity.
- Low speed operation
Motors need to reduce their output torque under 30Hz operation.
The cooling method of motors are their fans on shafts. At low speed, their speed are decreasing,
and their cooling efficiency are also decreasing.
Special motors for inverter drives are not necessary to reduce their output torque between 6 to 60Hz.
- Electromagnetic noise
The inverter is generating "electromagnetic noise".
If there are some high accuracy sensors or other sensitive equipment near the inverter drive,
the inverter's noise may cause some trouble or a malfunction.
Electromagnetic noise can be avoided by installing an external noise filter or
using a different wiring method.
- Harmonics
The inverter is generating "harmonics".
These harmonics sometimes cause a malfunction in other control equipment
that is connected to the same power source.
Harmonics can be avoided by installing an external "reactor".
To decrease "harmonics", we recommend to install DC reactors in all our inverter models.
(NOTE: 100V input models require AC reactors.)
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