Applied Motion ST10-C-CE - Manual (Page 44)

44
ST5/10-Si,-Q,-C, -IP Hardware manual 920-0004 Rev. F
6/10/14
Motor Heating
Step motors convert electrical power from the driver into mechanical power to move a load. Because step
motors are not perfectly efficient, some of the electrical power turns into heat on its way through the motor.
This heating is not so much dependent on the load being driven but rather the motor speed and power sup-
ply voltage. There are certain combinations of speed and voltage at which a motor cannot be continuously
operated without damage.
We have characterized the recommended motors in our lab and provided curves showing the maximum duty
cycle versus speed for each motor at commonly used power supply voltages. Please refer to these curves
when planning your application.
Please also keep in mind that a step motor typically reaches maximum temperature after 30 to 45 minutes
of operation. If you run the motor for one minute then let it sit idle for one minute, that is a 50% duty cycle.
Five minutes on and five minutes off is also 50% duty. However, one hour on and one hour off has the effect
of 100% duty because during the first hour the motor will reach full (and possibly excessive) temperature.
The actual temperature of the motor depends on how much heat is conducted, convected or radiated out of
it. Our measurements were made in a 40°C (104°F) environment with the motor mounted to an aluminum
plate sized to provide a surface area consistent with the motor power dissipation. Your results may vary.
HT34-504/505/506 with ST10
�� VDC power supply, ����� steps/rev, all motors connected in parallel
0
100
200
300
400
500
600
700
800
900
1000
0 5 10 15 20 25 30 35 40
oz
-in
rev/sec
HT34-506 (6.72 A/phase)
HT34-505 (7.56 A/phase)
HT34-504 (7.56 A/phase)