Control Engineering Motors, Drives, & Motion Control Newsletter for January 2002

By Frank Bartos June 4, 2002

In this issue:

  • Update on contactors, motor starters
  • Readers surveyed on motion control
  • Chip-based motion developer’s kit for PCI bus
  • Rare-earth magnets in ring form
  • Motor controller for $100
  • New Technical Working Group for SERCOS N.A.
  • Exhibitions, seminars
  • Control Engineering in January
  • Companies in motion
  • Control Engineering News

Update on contactors, motor starters

Less publicized than other technologies, products for starting and protecting electric motors continue to make refinements that might interest you.

Siemens Energy & Automation, Inc. (Alpharetta, Ga.) recently introduced three sizes of large-frame contactors with ratings in the 115-500 A range for ac or dc motor control. The new product line fits into and expands Siemens’ Sirius 3R system of modular, compact contactors, overload relays, motor starter protectors, and associated devices beyond the previous 100-ampere level. These contactors feature a system of ‘Universal Current’ coils that allow coverage of control voltages from 24 to 600 V (ac and dc) with just 13 coil ranges. This helps cuts users’ inventory from the more typical 50 coil ranges.

Coil options for Sirius 3R contactors offer a choice of standard coil plus three electronic coil versions. The latter options include 1) an interface for direct switching of a PLC without adding relays or PLC interfaces 2) ‘Remaining Lifetime’ indication for estimating contact erosion by a quick visual inspection, which eliminates down time due to worn contact tips, and 3) AS-Interface to accommodate digital communication.

To visit Siemens E&A’s website, click

Also new from Eurotherm/Barber-Colman (Leesburg, Va.) is a solid-state contactor and power controller combo. The second member in the new Series 7000 range of power products, Model 7100S Solid State Contactor/SCR Power Controller is a single-phase unit rated from 16 to 100 A (100-500 V ac). It includes ac logic, dc logic, or 4-20mA control input. Optional diagnostics features, such as monitoring of SCR failure, total load failure, and partial load failure add value to the product, allowing faster user response to emergencies and maximizing production downtime. Model 7100S carries the CE Mark for use in Europe; UL/cUL approvals are in planning.

To visit Eurotherm’s website, click

A ‘simple, compact alternative to traditional combination starters’ is how Sprecher + Schuh (Houston, Tex.) refers to its newly introduced CX7 combination enclosed starter. CX7 needs only two major elements: a motor circuit controller (KT7) and a contactor (CA7) for remote operation. Separate traditional items, such as an overload relay and short-circuit protection, are said to be eliminated by combining multiple functions into the KT7 controller. Fewer parts and smaller dimensions translate into a smaller enclosure and lower unit cost. Sprecher + Schuh’s CX7 starter handles motors up to 30-hp size (at 460 V ac). It supplies current limiting short-circuit protection up to 65 kA, along with Class 10 thermal overload protection.

To visit Sprecher + Schuh’s website, click

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Readers surveyed on motion control; care to comment?

Recently, I was involved in generating the questionnaire to an extensive ‘Motion Control Trends Survey’ of readers of Control Engineering and Design News magazines, conducted by Cahners Research. The collaborative survey explored the views of users and specifiers of motion technology. This and later newsletters will share some of the results with you, along with my analysis.

Among several types of motion controllers available, survey results found programmable logic controller (PLC)-based controllers still dominate the scene, with 81.5% of survey respondents indicating current use. However, little growth is seen in the next 18 months (4.3%). Personal computer (PC)-based motion controllers are moving up. More than half of respondents (55.3%) currently use them; another 14% contemplate near-future usage. Hybrid controllers, combining PLC- and PC-based features, drew relatively low response for present and future use (37.5%), again over the next 18 months.

Nearly 44% of respondents use board-level motion controllers and will in the near-term future. Chip-based motion controllers came in at 24.1% response. However, this youngest motion controller technology indicates the highest projected growth rate over the next 18 months.

Additional details from this comprehensive survey will appear in the March 2002 issue Control Engineering and Design News .

Do you have comments on these findings? Email

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Chip-based motion developer’s kit for PCI bus

Performance Motion Devices Inc. (PMD, Lexington, Mass.) offers a ‘Motion Control Developer’s Kit (DK) for the PCI bus’ priced at $995 for immediate delivery. PCI DK allows users to develop and evaluate single- or multi-axis motion control applications based on a variety of motor topologies — for example, brush dc, brushless dc, and stepper (including microstepping). The kit contains a PCI motion control board, with either a PMD Pilot [single-axis motion] or Navigator [multi-axis motion] chipset, suitable cabling, manuals, and a CD-ROM with PMD’s C-Motion Library and Pro-Motion graphical interface.

The Developer’s kit supports the chipset’s full features, such as s-curve motion, electronic gearing, advanced PID filter, limit switches, and I/O points on each axis. For example, a kit with Navigator MC2340 chipset installed can control up to four brushless motors and provide on-board commutation for each axis, as well. ‘Multiple PCI boards can be installed and synchronized to within 10 microseconds,’ says the company. For programming the developer’s kit, Pro-Motion interface provides convenient dialog boxes and point-and-click functions.

To visit Performance Motion Devices’ website, click

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Rare-earth magnets in ring form

The performance benefits of high-energy, rare-earth magnets for motors, actuators, and other devices are well known by now. However, manufacturing magnet materials like Neodymium-Iron-Boron can be complex and costly. Here is one recent development to makes working with rare-earth magnets easier.

Magnetic Component Engineering Inc. (MCE, Torrance, Calif.), a manufacturer of permanent magnets and magnetic assemblies, now produces radially oriented, sintered Neodymium-Iron-Boron (Nd-Fe-B) magnets in ring form. The ring configuration opens cost-effective options for designers working on new products or improving existing ones. Because MCE manufactures the radially oriented rings in one-piece, all grinding processes-and surface treatment, if needed-can be done prior to the magnetizing and assembly steps. ‘Assembly costs are dramatically reduced, and assembly can be easily automated for mass production,’ says a company spokesperson.

In the past, these magnets were fabricated in segments (or arcs), and sets of magnet arcs had to be assembled to obtain a ‘ring’ with a radially oriented magnetic field. Eight to 12 arcs, oriented through a common centerline, composed a typical ring. While high-performance magnet assemblies could be produced, the process posed problems. ‘The cost of magnets and labor to assemble the arcs into a ring was prohibitive for large productions. Generally, the magnet assembly required in-process grinding operations to ensure tolerances after assembly,’ according to MCE. And, often, the grinding step had to be done after the magnets were magnetized, adding to cost.

MCE makes radially oriented rings from various magnetic materials with energy products — or magnetic field strength values — ranging from 28 to 40 MGOe [Megaoersted].

To visit Magnetic Component Engineering’s website, click

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Motor controller for $100

Are you looking for simple, low-cost control for brush dc motors? Yes, lots of dc motors are out there in active applications.

ICON H-Bridge module from Solutions Cubed (Chico, Calif.) may be what you need. This compact package simplifies digital control of brush dc motors with ratings up to 12 A continuous current (25 A peak) and 40 V dc supply. ICON H-Bridge contains four MOSFETs and is the core module of the company’s new dc motor control system. Parameters, such as system load current, board temperature, overcurrent and overtemperature trip points, etc., are programmed in configuration registers and monitored via the serial interface. Overcurrent and overtemperature are monitored by a microcontroller. And not least significant is the $100 single piece price of ICON H-Bridge.

To visit Solutions Cubed’s website, click

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New Technical Working Group for SERCOS N.A.

The North American Promotional Alliance for SERCOS (SErial Realtime COmmunications System) interface-SERCOS N.A., (Bloomingdale, Ill. )-announced in mid-December 2001 the formation of a technical working group (TWG). Group members consist of motion control engineers tasked to expand and improve the SERCOS protocol for motion control, according to Ronald Larsen, managing director of SERCOS N.A.

Present task of the North American TWG’s is to specify advanced conformance testing requirements for SERCOS interface products to ensure that various manufacturers’ products are compatible and interoperable at the ‘SERCOS Conformance Class A level.’ More than 70 suppliers worldwide currently offer SERCOS products. Mr. Larsen invites persons interested in the technical enhancement of SERCOS interface to join the working group at no charge, whether or not their company is affiliated with one of SERCOS’ trade associations.

SERCOS is the standardized, digital interface (IEC 61491) for communication among controls, digital drives, and I/O modules. It is based on a fiberoptic ring with transmission rates up to 16 Mbit/sec.

To visit SERCOS N.A.’s website, click

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Exhibitions, seminars

IFPE 2002-International Exposition for Power Transmission-is slated for a five-day run, March 19-23, 2002 in Las Vegas, Nev. Some 400 exhibitors are expected at this presentation of hydraulic, pneumatic, electrical, and mechanical products and systems used in motion control. A technical conference will take place during the first three days of the show (March 19-21). For more information, call 800/867-6060 or register online at .

The 1st International IEE Power Electronics, Machines and Drives Conference (PEMD 2002), will be held at the University of Bath (Bath, U.K.), April 16-18, 2002. This conference provides a forum for recent developments and trends in the areas of electrical machines, drives, solid-state motion control, and power conversion. A technology exhibition will be in session along with the conference. PEMD 2002 is organized by the Power Conversion and Applications Professional Network of the IEE and is cosponsored by the Power Engineering Society of the Institute of Electrical & Electronic Engineers. For more information, visit

In a related arena, the 3rd International Fluid Power Conference is set to run in Aachen, Germany, March 5-6, 2002. Dedicated to the exchange of knowledge and experience between industry and science, the symposium carries the theme of ‘Fluid Power Focused on Applications.’ Some 80 presentations by speakers, a poster session, and an exhibition comprise the conference, organized by the Institute for Fluid Power Drives and Controls (IFAS) at the RWTH Aachen. For more information, visit

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Control Engineering in January

Each in-print issue of the magazine contains information for your perusal on motors, drives, and motion control.

In the first issue of 2002, our ‘Technology Update’ department kicks off with a short article on how ‘observers’ can improve resolver conversion in motion systems. George Ellis, senior scientist at Kollmorgen (Radford, Va.), discusses the effect of an observer on servo system response and how the technique of resolver digital conversion comes into play.

To visit Kollmorgen’s website, click

January’s Online page summarizes four developments, two of which should have an appeal to our special audience. ASI Robicon’s (New Kensington, Pa.) modular medium-voltage, variable-frequency drive that has an ‘Advanced Cell Bypass’ feature with redundant capabilities to minimize production interruptions is presented in a refinery application . Use of constant-voltage transformers for power conditioning is described in a ‘ Back to Basics ‘ article from Sola/Hevi-Duty (Skokie, Ill.). The full articles can be accessed at / ; look under ‘More from January 2002.’

To visit ASI Robicon’s website, click ; for Sola/Hevi-Duty’s website, click

In this month’s Products & Software section, California Linear Devices Inc. (Carlsbad, Calif.) features its new direct-drive linear motor family with peak force ratings up to 1,200 lb and standard stroke lengths of 2-18 inches. Easy configuration, even for multiple motion axes, is the focus of new Modular Drive System (MDS) from Control Techniques (Eden Prairie, Minn.). MDS consists of up to three power modules and up to eight drive modules that operate in velocity, torque, or pulse type of control.

To visit California Linear Devices’ website, click ; for Control Techniques, click

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Companies in motion

In early December 2001, Cimetrix (Salt Lake City, Ut.) announced the opening of a new European office in Archamps, France, just outside of Geneva, Switzerland. Named Cimetrix Europe Inc., the office will expand global sales and support for the company’s recently introduced PC-based motion control software package. This is CODE 6 (Cimetrix Open Development Environment version 6) with Core Motion technology, which is said to eliminate the need for intelligent motion cards and drastically cut hardware costs.

To visit Cimetrix’s website, click

ABB (New Berlin, Wis.) has recently been awarded a $29-million order from the U.S. Air Force for large drives and motors at the Arnold Engineering & Development Center’s, (AEDC) Propulsion Wind Tunnel facility (Tullahoma, Tenn.). Most of the turnkey project’s value ($22 million) goes to two new 69,000 hp ABB Medium Voltage (MV) ac drives and motors, replacing two 40,000 hp motor/drives.

Wind tunnel facilities at AEDC can simulate flight velocities from subsonic to more than Mach 20 and conditions from sea level to altitudes up to 100,000 ft. Depending on test requirements, the new ABB drives can power the wind tunnel’s fans in 1) adjustable-speed mode or 2) start up and synchronize the two 83,000-hp, fixed-speed motors to run at a constant speed. These MV drives supply a maximum power of 304,000 hp at 600 rpm. ABB, New Berlin, is the main contractor on the project, with ABB Industrie AG, Switzerland, providing the power electronics, and Cutler-Hammer Engineering Services responsible for construction services.

To visit ABB’s website, click

Beckhoff Automation LLC (Minneapolis, Minn.) now offers direct sales and support for its PC-based control solutions — including software-based motion control. Among direct services provided are configuration support, application engineering, and honoring of warranties to existing customers. Six offices in the U.S. and one in Canada are involved in the expanded direct support effort. Beckhoff’s recent announcement coincides with the termination of the distributor relationship with Interlink BT (Plymouth, Minn., ). The parent company, Beckhoff Industrial Electronics (Verl, Germany), claims 15 years of expertise in PC-based control, including hardware and software products.

To visit Beckhoff’s website, click

Intelligent Motion Systems Inc. (Marlborough, Mass.) is expanding its integration of stepper motors with on-board electronics by adding a NEMA size 34 MDrive to its product lineup. MDrive34 combines a high-torque step motor and driver in a compact package. It follows earlier introductions of MDrive17 and MDrive23, which integrated similar packages around smaller size motors. More detail on these products is available in CE, Dec. 2001, ‘ Integrated, Intelligent Motors & Controls Will Be in Your Future .’ ( Control Engineering , December 2001 issue.) MDrive34 will make its debut in March at National Manufacturing Week 2002, in Chicago.

To visit Intelligent Motion Systems’ website, click

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Control Engineering News

  • Is your company involved in FDA’s 21 CFR Part 11 Electronic Records and Signatures regulation? Please take a survey at ; results will appear in an April 2002 Control Engineering article.

  • Register for a free Control Engineering -moderated webcast: ‘FOUNDATION Fieldbus: An Open, Integrated Architecture for Information Integration.’ See details at /webcast/archives/fieldbus.htm

  • Control Engineering Online includes eight topical e-mailed newsletters, Daily News, Control Engineering Europe , and searches of the site, Control Engineering Buyer’s Guide , and Automation Integrator Guide Online ; go to /

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