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NI's Stepper Motor Drives (SMDs) support two-phase stepper motors, including four-wire, six-wire, and eight-wire bipolar motors. Six-wire and eight-wire motors can be wired in parallel or series; reference the drive manual for wiring diagrams and compatibility notes. When matching a stepper motor to a NI stepper drive, the two largest considerations to take into account are the current and inductance specifications of the motor. In order for a stepper drive to be compatible with a specific stepper motor, current and inductance specifications of the motor must match the allowable range of the drive and will vary based on whether it is wired in series or parallel.
The table below gives the current and inductance ranges of the current NI SMD product line.
| NI SMD Drive | Minimum Inductance (mH) | Maximum Inductance (mH) | Maximum Phase Current Range (A) |
| 7613, 7615 | 1 | 6 | 0.5-5.0 |
| 7614, 7616 | 1 | 6 | 0.5-10.0 |
| 7620 | 5 | 20 | 0.5-5.0 |
| 7621 | 20 | 60 | 0.5-2.55 |
It is also important to ensure that a motor and drive combination can provide the required torque at a given speed for the application. The user manual for each NI SMD lists the NI stepper motors that are compatible with that specific drive based on current and inductance specifications for both the motor and drive. Moreover, the stepper drive manuals also provide torque-speed curves for paired motors based on power supply voltage.
NI SMDs automatically account for anti-resonance, which is based on the ratio of holding torque to rotor inertia. As a result of this, for all third party motors, it is recommended to use the Ethernet-connected SMD-7613/7614/7615/7616 or SMD-7620/7621 because these settings are configurable through the NI Stepper Configuration Utility. The SMD-7610/7611/7612 should only be used with NI stepper motors.