FAQ Index

Q: Why would one choose a 3 Phase Motor over a Single Phase Motor?

A: Three-phase motors are more cost-effective, and compact than single-phase motors with the same rating and voltage. Single-phase AC motors above 10 HP (7.5 kW) are typically not as common. Three-phase motors vibrate less, therefore extending their lifetime longer than single-phase motors of the same power, used under the same conditions.

Q: What is the difference between a variable frequency drive and a variable speed drive?

A: Variable frequency drives (VFD) typically refer only to AC drives, while variable speed drives (VSD) can pertain to either an AC Drive, or a DC Drive. VFD's control an AC Motor's speed by varying the motor's frequency. VSD's on the other hand, vary voltage in order to control a DC motor.

Q: Can I reverse the rotation direction of the AC Induction motor if I wired it as shown on the catalog, for example, ACP-M-4IK25N-AU?

A: Yes, you can. However, ensure the motor completely stops prior to switching the direction. If immediate reversing is needed, reversible motor is better suited for the application; for example ACP-M-4RK25N-AU.

Q: Can the speed of AC Induction Motors and Reversible motors be changed?

A: Power supply frequency determines the speed of single-phase (AC) induction and reversible motors. If your application necessitates a changing speed, a speed control motor is recommended.

Q: Will temporarily storing my AC Induction Motor in an environment of 0°F to -20°F create any problems?

A: Extreme temperature changes might lead to condensation inside the motor. If this happens, components may rust, greatly shortening the service life. Do your best to avoid the occurrence of condensation.

Q: Is it bad if my AC Induction motor runs extremely hot?

A: When converting electrical energy to rotational movement, heat is generated within the motor, making it hot. The AC Motor's temperature is equal to the temperature rise caused by loss within the motor, plus the ambient temperature. If the ambient temperature is 85°F, and the internal loss within the motor is 90°F (32°C), the surface of the motor will be 175°F (79°C). This is not atypical for a small motor.

Q: Why is it that some AC motor gear heads output oppositely of the motor, while others output in the same direction?

A: Gearheads reduce the motor speed anywhere from 1/3 to 1/180 (For AC Induction Motors.) This speed reduction is a result of multiple gears; the number of gears depending on the amount of speed reduction. However the last gear rotates determines the direction of the output shaft.

Q: Will an AC Induction Motor be affected by large fluctuations in power supply voltage?

A: The power supply voltage affects the torque produced by the motor. Torque is equal to approximately two times the power supply voltage. Thus, when using motors under large power voltage fluctuations, it is important to remember that the generated torque will vary.

Q: Will Anaheim Automation mount a brake or encoder on an AC Motor?

A: Yes, a special part number would be created that would include the desired AC Motor configured with an Accessory product.

Brush DC FAQ

Q: What variables contribute to Brush DC Motor noise?

A: Motor mounting in application, load and speed of the motor, type of bearings all play a role in motor noise.

Q: When do I use a Planetary, and when do I use a Spur Gearbox?

A: For a low current consumption, low noise and high-efficiency application, a Spur Gearbox would be the better choice. Applications with higher torque, higher current consumption, lower efficiency and higher audible noise levels, one should consider a Planetary Gearbox.

Q: What is Backlash?

A: Backlash is the clearance between mating components. Theoretically, backlash should be zero, but in practice some backlash should be allowed to prevent jamming. This is accounted for specially in reversing mechanical designs. Generally the greater the accuracy the smaller the backlash needed. Backlash is most commonly created by cutting the teeth deeper into the gears than the ideal depth. Another way of introducing backlash is by increasing the center distances between the gears.

Q: Does a Brush DC Motor need to run at the rated voltage?

A: No, however it is recommended to run the motor slower or less than the nominal voltage. The Brush DC Motor life can be affected by the speed of operation. Operating at a lower voltage means lees brush/commutator wear on the Brush DC motor, also lower current consumption means longer Brush DC Motor life.

Q: Are Anaheim Automation's Brush DC Motors reversible?

A: Yes, this can be easily done to by reversing the polarity on the Power Supply.

Q: What is the primary difference between a Brush DC Motor and a Brushless DC Motor?

A: Because of brush wear, a Brush DC Motor needs maintenance and has shorter life than Brushless DC Motors. Brushless DC Motors require of an Electrical Speed Controller, but offer higher efficiency.

Q: Can different voltages be applied other than the specified voltage?

A: Yes, you can apply different voltages, although, you must keep in mind that there is a speed limit for the bearings. If you increase the voltage the speed will increase, if you decrease the voltage than the speed will decrease.

Q: How can I get/achieve a higher power output without purchasing a new motor?

A: This can be approached in two ways, either by increasing the voltage being applied or increasing the current being supplied to the Brushless DC Motor. The equation:
Power = (Oz – in x ω)           Power = Watts (W)
           1351.2           ω = Speed (RPM)

Q: What is the difference between a DC Brushed Motor and a DC Brushless DC Motor?

A: A DC Brushed Motor needs physical contact to pass current through its motor windings to allow commutations. A Brushless DC Motor needs a driver to commutate.

Q: Do Hall Sensors need to be used to drive a Brushless DC Motor?

A: No, Hall sensors are only needed for feedback systems requiring a Hall Effect Sensor. A Brushless DC Motor may be sensorless where the back EMF is used to run the motor.

Q: What is Stall Torque?

A: Stall Torque is the amount of torque where the shaft ceases to move.

Q: What is Rated Torque?

A: Rated Torque is where the motor can operate continuously at a safe level.

Q: What is Peak Torque?

A: Peak Torque is where the motor can operate at a brief moment in time or until the motor self-destructs.

Q: Can I run a Brushless DC Motor off of a battery?

A: Yes, with a driver/controller.

Q: Can I run a Brushless DC Motor off of 110 VAC?

A: Yes, with a driver/controller.

Q: Will a Brushless DC Motor slow down when the load is increased?

A: No in closed loop it the torque of the motor is strong enough, but always in open loop.

Q: Is it possible to burn up a Brushless DC motor giving it too much load?

A: Not if the drive current limit is set correctly.

Encoders FAQ

Q: What is an encoder?

A: An encoder is a sensor of mechanical motion that generates digital signals in response to motion.

Q: What is the difference between absolute and incremental encoders?

A: Absolute and incremental encoders are different in two ways:
Every position of an absolute encoder is unique
An absolute encoder never loses its position due to power loss or failure. Incremental encoders lose track of position upon power loss or failure

Q: What is a channel?

A: A channel is an electrical output signal from an encoder.

Q: What is a quadrature?

A: A quadrature has two output channels, with repeating squarewaves, which are out of phase by 90 electrical degrees. From the phase difference, the direction of rotation can also be determined.

Q: What is an index pulse?

A: The index pulse, also referred to as a reference or marker pulse, is a single output pulse produced once per revolution.

Q: What other types of encoder technologies are there?

A: There are two types of encoder technologies.
Optical: This type of technology uses a light shining into a photodiode through slits in a metal/glass disk.
Magnetic: Strips of magnetized material are placed on rotating discs and are sensed by Hall-Effect Sensors or magneto-resistive sensors.

Q: What types of applications are encoders implemented in?

A: They are frequently utilized in stepper motors, automation, robotics, medical devices, motion control and many other applications requiring position feedback.

Q: Does any encoder disk (codewheel) work with any encoder module?

A: No, each resolution and each disk diameter works with a different encoder module.

Q: What is PPR?

A: PPR stands for pulse per revolution in rotational motion for rotational motion and pulse per inch or millimeter for linear motion.

Q: When can a single output channel be used in an incremental encoder?

A: A single output channel for an incremental encoder can be used when it is not important to sense direction. Such applications make use of tachometers.

Q: Will Anaheim Automation mount an encoder to motors?

A: Yes, a special part number would be created for including the encoder attached to a motor.

Gearbox FAQ

Q. Are planetary and spur gearboxes bi-directional?
A. Yes, planetary and spur gearboxes are designed to be used for bi-directional operation. The direction the input shaft rotates and gear arrangement of the gearbox will determine the rotation of the output shaft.

Q. Can Anaheim Automation's motors be combined with a gearbox?
A. Anaheim Automation's motors can be assembled with a gearbox to meet the necessary requirements of an application. Motors and gearboxes can be purchased separately or be purchased as an assembled unit. Customization is available. Minimum purchase requirements and a Non-Cancellable/Non-Returnable agreement will apply.

Q. What is the lifetime of Anaheim Automation's motors and gearboxes?
A. Yes, planetary and spur gearboxes are designed to be used for bi-directional operation. The direction the input shaft rotates and gear arrangement of the gearbox will determine the rotation of the output shaft.

Q. What type of gearbox would be used for right angle applications?
A. A bevel and worm gearboxes are mainly utilized in right angle applications. They offer high efficiency and low gear ratios. A straight bevel gearbox with straight cut teeth are utilized in slow speed applications, whereas spiral bevel gearboxes with curved teeth are utilized in high performance, high speed applications. Worm gearboxes are also available with right angle configurations. They are able to sustain high shock loads, low in noise, maintenance-free but are less efficient than bevel gearboxes.

Q. Can gearboxes be backdriven?
A. Some gearboxes, such as spur gearbox can be backdriven, while some, such as the worm gearbox cannot be backdriven.

Q. How many planet gears are there in a gearbox?
A. The amount of planetary gears in a gearbox differs based on specific application requirements. Most planetary gearboxes consist of two or more planetary gears.

Q. What is the difference between straight cut gears and helical gears?
A. Straight cut gears have straight and tapered teeth, and are used for low speed applications. Helical gears are cut at angles to allow gradual contact between the gear teeth. This allows for smooth and quiet operation. Helical gears are applicable in high horsepower and efficient applications.


Q: Do HMIs have printing capabilities?

A: It varies depending on the manufacturer. Some HMIs will come with specific printers that are compatible, while others will not have printing capabilities. Some HMIs have the capability to install the user's own drivers for the printer of choice.

Q: How does one program an HMI?

A: There are a few third party programs that can be used to create an HMI graphical user interface, such as CodeSys and EV5000. Some HMIs come standard with their own proprietary software, which provides the functions specific to that HMI. Lastly, some HMI's come with SDK packages so the user can program the HMI in his/her native language.

Q: What does an HMI do?

A: With an HMI the user will have a centralized unit of control, which allows for decisions based on real time events in a visual manner. That HMI must be in constant communication with a controller so the HMI can receive real time data from controller. The HMI accesses specific registers on the controller and makes decisions based on the state of those registers. Most controllers deal with heavy wiring, and without a user interface they require manual input (wiring) to toggle certain registers. This is accomplished through software and makes the application simple and easy to perform.

Q: How does the HMI communicate with other devices?

A: The HMI must be connected to a device, whether it is through Ethernet (RJ45), serial communication (RS232, USB or RS422), or wireless. The two devices baud rates must be in sync, so that no miscommunication occurs.

Q: What if my controller is not supported by this HMI?

A: If the software that came with the HMI does not have a universal controller option, then third-party software may be used. Most software has a generic universal controller, in case the controller being used is not considered compatible with the HMI.

Q: What are the benefits of an HMI over a desktop?

A: An added benefit of an HMI is that it is application-specific. In other words, a panel will not allow for internet browsing, solitaire game play, or update reminders unless it pertains to the task at hand. HMIs provide absolute control; meaning that you may give the user limited access to specific features, or full access depending on how the interfaces are created. (See Advantages of an HMI).

Q: What is the AC Servo Motor Efficiency?

A: Generally, 95%.

Q: Can the SRMD support ladder logic?

A: Yes.

Stepper FAQ

Q: Why is the step motor size important? Is it possible to just choose a large motor size?

A: The step motor size is important because if the motor's rotor inertia predominately consists of the load, resonance increases and poses issues. Also, larger rotors require more time to accelerate and decelerate and therefore it is important to choose a motor size dependent on the criteria for user applications.

Q: While increasing speed, why do step motors lose torque?

A: Inductance is the leading cause for motors losing torque at high speeds. The electrical time constant, τ, is the amount of time it takes a motor winding to charge up to 63% of its rated value given a resistance, R, and inductance, L. With τ = R/L, at low speeds, high inductance is not an issue since current can easily flow through the motor windings quickly. However, at high speeds, sufficient current cannot pass through the windings quick enough before the current is switched to the next phase, thereby reducing the torque provided by the motor. Therefore, it is the current and number of turns in the windings which determines the maximum output torque in a motor, while the applied voltage to the motor and the inductance value of the winding will affect on the speed at which a given amount of torque can be produced.

Q: Why does increasing the voltage increase the torque if step motors are not voltage driven?

A: Voltage can be viewed as forcing current through the coil windings. By increasing voltage, pressure to force current through the coil also increases. Therefore, this vast amount of current being forced through the coil causes it to saturate which results in loss of torque and increase of speed.

Q: What temperatures are step motors able to run at?

A: Most step motors include Class B insulation. This allows the motor to sustain temperatures of up to 130° C. Therefore, with an ambient temperature of 40° C, the step motor has a temperature rise allowance of 90° C allowing for step motors to run at high temperatures.

Q: Is it possible to get more torque by running the step motor at double its rated current?

A: It is possible to increase torque by increasing the current but by doing so, it weakens the motor's ability to run smoother.

Q: What is the difference between four, six and eight leads in motors?

A: Stepper motors have the capability to run in either parallel or series modes. In a parallel mode, only a four lead motor can be run while in a series mode a six lead motor can be run. Eight lead motors can run in either parallel or series configurations. In applications where more torque is required at higher speeds, a lower inductance value given from a four lead motor is better choice.

Q: What is the difference between Unipolar and Bipolar motors?

A: A unipolar wound motor has six lead wires with each winding having a center tap. Most applications implementing unipolar wound motors require high speed and torque. On the other hand, a bipolar wound motor has four lead wires with having no center tap connections. Most applications implementing bipolar wound motors require high torque at low speeds.

Q: What is the difference between a closed-loop step motor controller and an open-loop step motor controller?

A: In an open-loop step motor controller, no feedback is going from the motor to the controller. This type of controller is effective when the motor is carrying a constant load at a steady speed. A closed-loop motor controller is more applicable in applications where load or speed varies. In comparison to the closed-loop controller, the open-loop controller lacks complexity and is more affordable.

Q: When should I use microstepping?

A: Microstepping is typically used in applications which require the motor to operate at less than 700 pulses per second.

Q: What do brakes do on a Stepper Motor?

A: Brakes do not slow the shaft of a motor, they only hold it in place. If 24V is supplied to the brake, the brake is "released" and the motor shaft is free to spin. If 24V is not supplied to the brake, it locks position, and holds the motor shaft in place.

Q: What is the difference between a round and square stepper motor?

A: A round (D and W series) motor is an older style design with a flatter T/S curve. They offer more torque at a higher RPM than the square (Y or L series) motors. The square motors offer more torque at lower RPM.