Applied Motion STR4 - Manual (Page 18)

18
STR4/8 Hardware Manual 920-0030J
5/12/2015
Step 2: Setting the Current
The maximum current for the motor you have selected is set automatically when you set the
rotary switch. But you may want to reduce the current to save power or lower motor tempera-
ture. This is important if the motor is not mounted to a surface that will help it dissipate heat or
if the ambient temperature is expected to be high.
Step motors produce torque in direct proportion to current, but the amount of heat generated
is roughly proportional to the square of the current. If you operate the motor at 90% of rated
current, you’ll get 90% of the rated torque. But the motor will produce approximately 81% as
much heat. At 70% current, the torque is reduced to 70% and the heating to about 50%.
Two of the small DIP switches on the front of the STR drive are used to set the percent of rated
STR8 Motor Table
Motor Wiring Drive Cur-
rent Amps,
peak of sine
Holding Torque
oz-in
Rotor Inertia
g-cm 2 Switch
0
reserved for custom configurations 1
2
3
HT23-603 parallel 6 354 750
4 HT23-394/594 parallel 3.4 76.6 120
5 HT23-398/598 parallel 5 177 300
6 HT23-401/601 parallel 5 264 480
7 HT24-100 4 leads 3.36 123 280
8 HT24-105 4 leads 4.8 177 450
9 HT24-108 4 leads 4.8 354 900
A HT34-485 parallel 8 507 1400
B HT34-486 parallel 8 965 2680
C HT34-487 parallel 8 1439 4000
D HT34-504 parallel 7.56 396 1100
E HT34-505 parallel 7.56 849 1850
F HT34-506 parallel 6.72 1260 2750