Applied Motion STR4 - Manual (Page 33)

33
STR4/8 Hardware Manual 920-0030J
5/12/2015
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HT34 with STR8
Connection: Parallel
Power Supply 60V, 20,000 steps/rev
HT34-485 HT34-486 HT34-487
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 supply 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.