The torque illustrated in these torque curves is known as pull out torque, the maximum torque that can be applied to the rotating shaft of a stepping motor at a given pulse rate, under specified drive conditions, without missing steps.

The torques are for half step operation (400 steps/rev).

Torques are approximate and slight statistical variation may occur between individual motors and drives.

Stepper motors can run upto 3000 rpm, although this should be for intermittent periods. Running at speeds in excess of 2000 rpm for more than one hour will cause the motor to overheat, possibly demagnetising the rotor.

The torque curves do not take into account the effects of the inertia ratio (load/motor) which should be between 1:1 and 5:1.

The parallel mode is the recommended connection. When using parallel mode, set the drive current to no more than the bipolar motor rated current. If using series mode, set the drive current to half the bipolar motor rated current. H series motors only have 4 leads so they cannot be connected in series mode.

Alternative drives are shown in the torque curves, however, this is a guide only. The torque may vary from different drive models. 

Torque curves are also on back of SD stepper motor brochures.

Contact Automated Motion Systems for torques outside this range.