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General Stepper Motor FAQ

What kind of motor should I buy for my project?

There are many factors to consider when selecting the proper motor. Please refer to our Motor Selection Guide for more information.

Is my stepper motor compatible with the Phidgets 1062 or 1063 stepper controller?

The first thing you should do is check the data sheet of your motor to find the amount of current it is rated for. The 1062 can provide a maximum of 1A of current, and the 1063 can provide 2.5A of current. These figures are absolute maxima- running at the maximum current constantly will effect the life of the controller. As long as our controllers can provide the current your motor is rated for, there is a high likelihood that it is compatible. Keep in mind that you can always drive your motor with less than the rated current, however, the torque and speed of the motor will be less than expected.

Another important specification is the power supply the motor requires. The 1062 has a maximum power supply voltage of 12V, while the 1063 has a maximum of 30V. If your motor requires significantly more power, it is likely incompatible.

The last specification you should check is the coil inductance of the motor. If a motor needs to stop quickly or change directions, all of the energy associated with the momentum of the motor is flushed back to the controller. If the inductance of the motor is high enough (>10mH), this can quickly destroy the controller. This limitation only applies to the 1063, as the 1062 runs slow enough to avoid such a problem.

If you are still unsure, you can Contact Us.

Is my stepper controller compatible with the motors sold by Phidgets?

As long as your controller is able to provide the appropriate current and voltage specifications as mentioned in the previous answer, and uses a chopper drive, it should be compatible with any of the motors of the appropriate type (unipolar/bipolar) that we sell.

If you are still unsure, you can Contact Us.

Can I use a unipolar controller to run a bipolar stepper? Or a bipolar controller to run a unipolar stepper?

It is possible to use a unipolar controller to run a 6 or 8-wire bipolar stepper motor (but not a 4-wire, since it has no common "+" wire), but you will only get roughly half as much torque and speed because only half of each motor coil is energized at any given time. You could use a bipolar controller to control a 6 or 8-wire unipolar stepper (but not a 5-wire, since the coils are connected internally by the common "+" wire), as long as the motor's current and voltage specifications match up with what's being provided by the controller. In most cases it's just easier to select the appropriate type of motor and controller ahead of time.

Precisely how much torque does a specific motor provide?

Giving an accurate, meaningful figure for the torque of a motor is difficult because it varies depending on the current provided to the motor and the speed at which it’s presently rotating. The easiest way to compare the torque of motors is by using the holding torque- that is, the torque of the motor at standstill with the rated current applied to the coils. The holding torque is equal to the output torque specified by the manufacturer plus the detent torque.

At low speeds, the operating torque of the motor will be roughly equal to the holding torque minus twice the detent, since the motor is working against the detent torque while in motion. At high speeds, the torque will decrease significantly.

Can I simultaneously use multiple stepper controllers with the same computer?

Yes, you can use as many controllers as you can connect to your computer via USB (you can use a USB hub if you run out of ports). Simply create a unique object for each controller and open them using each board’s unique serial number.

Can your stepper motors and controllers allow the motor to be driven in forward and reverse without changing the wiring?

Yes, you can make a stepper rotate forward by setting a target position greater than the current position, and you can cause it to rotate in reverse by setting a target position less than the current position (negative values are acceptable). The wiring merely determines whether “forward” in this case means clockwise or counterclockwise rotation.

Can I set the stepper motor to rotate continuously?

By setting the target position to a very large number, you can effectively cause the motor to rotate continuously. The maximum value for target position is ±239, which is long enough to keep a unipolar motor on the 1062 rotating at maximum velocity for 45 years, or a bipolar motor on the 1063 for 194 days.

How do I connect a stepper motor to the Phidgets 1062 or 1063 controller?

Please refer to the 1062 or 1063 product page for a guide on connecting 4,5,6 and 8-wire stepper motors.

Can a stepper controller keep track of the number of steps made if the motor is turned by an external force (for example, rotated by hand)?

Stepper controllers are typically open-loop, meaning that the controller receives no feedback from the motor. If the motor is turned by an external force, or misses steps due to a heavy load, the controller will not count these steps and will lose track of the motor’s position. This could be corrected by including an encoder on the shaft of the motor to confirm the position, thus creating a closed-loop system.

Why is my stepper motor running with much less speed or torque than anticipated?

Ensure that you are supplying the proper rated current to the motor, and if the motor still under-performs, try using a higher voltage power supply.