BLDC Motors Now Available from Lin Engineering

Lin Engineering, one of the technical leaders in Motion Control, are very pleased to announce the release of their new Nema 23 line of Brushless DC (BLDC) motors.  The BLDC motors are available in both standard torque and high torque versions and are best for applications where high speed and high dynamic torque are necessary for the user.

BLDC motors perform best at speeds between 300RPM to 3000RPM.  They provide extremely quiet and smooth operation regardless of speed range. Brushless DC motors are also great for those who prefer velocity control with an analog input, do not need holding torque and may be having reliability issues with an existing Brush DC motor.  BLDC’s are also a good choice for applications that do not have a lot of power and require a higher efficiency motor.

For more information on the Nema 23 BLDC motors available through Lin Engineering, please contact us at 408-919-0200 or sales@linengineering.com

SilverPak 17T - New Smart Motor at Great Low Price

Santa Clara, CA—March 2006—Lin Engineering, the Step Motor Specialist, is pleased to introduce the newest addition to their line of integrated step motor/driver/controllers: the SilverPak 17T.  The SilverPak 17T is a bipolar, 1.8 degree, NEMA 17 step motor integrated with a microstepping driver/controller in order to provide easy system integration for newly designed applications.  Additional benefits of the SilverPak 17T are it’s affordable cost and smooth motion capability. 

The SilverPak 17T is available in body lengths of 2.76”, 2.99”, and 3.31” and is capable of producing up to 85 oz-in of holding torque, depending on the stack size of the motor. Custom windings are available at no extra cost in order to Maximize Torque at your Desired Speed.

The SilverPak 17T features selectable step resolutions from full step to 16x microstepping, output currents of 0.1 to 1.5 Amps peak, input voltage of 7VDC to 28VDC, and 16kBytes of memory.  There are two digital limit switches, one general purpose input and one open collector output capable of outputting 100mA.  Once programmed, the SilverPak 17T is capable of stand-alone operation with no connection to a PC and because there is low power dissipation, no heat sink is required.  The driver/controller uses Trinamic’s TMC428 and TMC246 microchips and is incorporated with the TMCL programming language.  The SilverPak 17T also features StallGuard™ encoder less stall detection

New SilverPak 23C, an Integrated NEMA 23 Step Motor, Microstepping Driver, and Controller in one Compact, Sleek Unit.

If you are looking for a simple yet powerful integrated unit for your application then Lin Engineering, the Step Motor Specialists, have the ideal solution for you. Lin Engineering is pleased to release the new SilverPak 23C, an integrated NEMA 23 step motor, microstepping driver, and controller in one compact, sleek unit.

The SilverPak 23C is available in three body lengths: 3.41”, 3.85” and 4.78” and is capable of up to 294 oz-in of holding torque depending on the stack size of the motor.  The unit is capable of up to 3 Amps Peak of output current, operates from +12 to 40 VDC, and can reach speeds of 16.7MHz. Some of the fully programmable features include but are not limited to: stand alone operation with no connection to a PC; fully programmable ramps and speeds; software selectable hold and move currents; up to 256x microstepping resolution settings; and four user configurable digital I/O’s. Commands can be issued from the Windows® HyperTerminal® program or from the SilverPak 23C Windows® application. The commands are intuitive yet simple and can be preset to execute upon power up.

Please visit the company website at www.linengineering.com for more technical specifications as well as downloadable SilverPak 23C Windows® program, quick reference guides, SilverPak 23C Windows® application programming examples and SilverPak 23C manual.

Having Trouble Choosing the right Step Motor and Driver Combination?

When it comes to precision in the motion control industry, there are many important factors that contribute to inaccurate steps.  As a total system, engineers must become knowledgeable of their step motor as well as their driver/controller units.

Believing that all the inaccuracy lies within the motor is very common.  From the step motor’s perspective there are tolerances to meet—both mechanically and electrically.  Phase imbalance in Inductance is a large factor, as well as pole misalignment, rotor misalignment, inconsistent air gap between rotor and stator, stator and rotor tooth relationship, and torque stiffness to name a few.  Although the list may seem overwhelming, it is not difficult to achieve and maintain. 

Inductance relies on two factors: the coils and the rotor magnet.  It is proportional to the number of turns per coil squared, therefore consistent inductance between phases is easy to achieve through correct winding of the motors.  Most step motor manufacturers have automatic winding machines that can maintain this consistency.  A proper rotor magnet must be used in order to maintain even inductance throughout the motor.  As for the other specifications, most of it is mechanical and as long as manufacturers have reliable, high quality parts as well as consistent grinding of the rotor and stator, then an accurate step motor can be easily made.  Lin Engineering holds a +/- 5% difference in Inductance between the two phases in a 2-Phase bipolar step motor.  This tight tolerance will allow a step motor to perform with a +/- 1.5 arc minute error during 64 microstepping for a 0.9° motor.  When specs are met, a step motor will do exactly what you tell it to do.

It is very important to note that drivers have a significant amount of impact on a step motor’s performance as well. Every step motor has a certain characteristic in performance.  Some motors are made to perform well at low speeds resulting in high inductance values while other motors are specifically used for high speed applications resulting in low inductance values.  Step motors can accommodate for any motion profile by changing the windings in the coils to meet the mathematical formulas associated with speed, torque requirements, current, resistance, and inductance.  Therefore, one driver will not perform the same amongst many step motors, and vise versa: one step motor will not output the same amount of torque with many different drivers.  So what is an engineer to do?

Lin Engineering recommends the following five steps to matching a motor and driver accuracy in a motion control system:

1. Contact Lin Engineering
2. Choose the motor (based on application and speed torque requirements)
3. Ensure that specifications of the motor inductance can be limited to a +/- 5 percent difference between phases
4. Choose the driver.  If possible, obtain a current waveform diagram of the driver.
5. Determine the availability of special features or options that can provide smoother motion

A straightforward solution to step motor versus driver accuracy is an integrated unit.  Lin Engineering’s SilverPak series are available in either NEMA 17 or NEMA 23 frame sizes and can also be purchased with an optional internal controller as well.  Please visit http://www.linengineering.com/site/products/integrated_Series.htm for more information on Lin Engineering’s line of integrated products. 

Q: For the step motor 5609M-01 (0.9deg step and 80 oz-in), how much side force can it take? Dan from Michigan

A:Hello Dan, for the 5609M-01 motor, the side force this motor can handle is 100N @ 0.37” from the front face. 

Q: Will RoHS compliant motors perform better or worse than non-RoHS motors?  Jenny Y., Anaheim, CA

A:Good question Jenny, the motors should not perform any differently.

Q:What are base steps? And how are they calculated? Tiffany, Indiana

A:Base step is the maximum microstep resolution (step/rev) that can be accomplished on a driver.