הנה מידע שמצאתי בGOOGLE GROUPS אם יש למישהוא מה להוסיף הוא מוזמן
in a properly
designed *consumer* system, the motor shouldn't get too hot (60-70 C) to
touch. Such consumer motors (Meade, etc.) typically use inexpensive
components (bearings and such) and the life of the motor unit can be
severely limited by higher temperatures. This is often true of the
bearing lubricants, which (there are tradeoffs here) cannot take the
continous high temperatures without polymerizing or breaking down.
...larry
i would be surprised at any application that did not use a "hold"
current. this current, along with the lack of forced air circulation
accounts for most of the heat buildup in a typical application
While turning, the windings are fed
pulses by the controller. The 'off' time is a lot less than the 'on'
time, so there's more time spent creating heat than dissipating it.
When the controller is on but not turning the motor, one winding gets
the current continuously.
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