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Articles from 1998 In July


Shock absorbers

Heavy-duty industrial shock absorbers feature a self-compensating design to provide smooth deceleration under changing conditions. The 2- and 3-inch bore models are targeted for use where velocities or loads may vary within the same application or across a range of equipment. Product catalog provides technical information including deceleration principles, product construction and function, time and force advantages, and self-compensation. A shock-absorber selection is also included.

ACE Controls Inc., 23435 Industrial Park Dr., Farmington, MI 48335, FAX (248) 476-2470.

Composites

MPC(reg) moldable phenolic composite material is for molding components that must endure high heat cycling and stress, yet provide resistance to cracking. This glass-reinforced material is targeted for molding powertrain and electric motor components where these components need to resist creep, maintain high strength and elastic stiffness, withstand high temperatures, and provide resistance to the chemicals found in automotive environments.

Rogers Corp., Box 188, Rogers, CT 06263.

On the cutting edge

Just like two heads are better than one, The Gillette Co. (Boston, MA) is betting that three blades on your razor are better than two.

The MACH3(TM) razor from Gillette, which hits stores this month, features three blades in a progressive configuration for "a better way to shave," according to Thomas Gallerani, vice president of the shaving technology laboratoryat Gillette.

The shaver evolved from a number of design approaches over a 20-year period, most notably the SensorExcel(TM) and other predecessors. After Gillette launched the first twin blade, Trac II(reg), in 1971, the thought was, "If two blades are good, why not three?" Gallerani adds.

The first prototypes of the three-blade approach in the 1970s meant an uncomfortable shave, with excessive pull and nicks. However, the MACH3's difference is that it evolved from older, established razors like the Sensor, Atra Plus, and Trac II and brought their existing technologies together in a whole new way, Gallerani says.

MACH3 features an ergonomically designed handle, and fits into a carrying case. The razor takes replacement cartridges, which are sold separately.

Gillette engineers prototyped and tested the razor, then converted it from prototype using Unigraphics CAD software from Unigraphics Solutions. Gillette then consumer-tested the product on men, who found the razor reduced the need to reshave because of the progressive alignment and diamond-like coating of the blades. The razor also removes 40% more hair than a two-blade system. The need to reshave is the biggest problem for the majority of men.

Cartridge

MACH3's cartridge is a plastic-molded component made from Noryl(TM), a proprietary blend of polystyrene and polyphenylene oxide. The cartridge features an open architecture to allow debris, such as hair and soap, that might otherwise clog the head, to flow freely through it. A forward pivot is built into the cartridge rather than the blade handle, which allows the three blades to stay in progressive alignment as they move across the face.

Indicator(TM) lubricating strip

The lubricating strip at the razor's top is composed of polystyrene and polyethylene oxide (PEO), which are blended and co-extruded, and aloe and vitamin E. The strip delivers PEO lubricant during the shave, dissolving and wearing with use to let the user know when shaving quality is no longer at its highest. Gillette tested the strip on men, and calculated the average rate of wear to determine when the blue stripe would dissolve.

DLC(TM) comfort edges

The blades' DLC coating is a non-metallic, semiconductor-like deposit of carbon, which has been converted to a diamond-like, non-crystalline material. The material is two to three times harder than steel, and is applied in an 800-angstrom-thick layer.

Blades

MACH3's cutting edges are positioned in a progressive configuration and made from stain-resistant carbon steel, which Gillette buys directly from suppliers in Japan, Sweden, and England. The blades are about 10% thinner than Gillette's regular blades, their thinnest yet, and are the first major blade innovation in this category since the 1960s, the company says. The blades are independently spring-mounted, like the predecessor MACH3 borrows much of its technology from, the SensorExcel(TM).

Microfins

The razor's microfins on the cartridge's guard element help urge hair out of follicles and provide a masking sensation to the shaving process, which, Gillette's laboratories found through research, contributes to overall shaving satisfaction.

MACH3 vs. SensorExcel

Here's a look at the new razor, as compared to its predecessor, the SensorExcel:

MACH3 SensorExcel

Dimensions: 51/4 inches long (cartridge to end of handle) 5 inches long (cartridge to end of handle)

11/2 inches wide, 1/2 inch long (cartridge) 11/2 inches wide, 1/4 inch long (cartridge)

Blades: Three, individually spring-mounted Two, individually spring-mounted

Microfins: Yes Yes

Lubricating strip: Indicator(TM) with Vitamin E and aloe Lubrastrip(reg) with water-activated moisturizers

Handle: Ergonomically shaped metal, with three rubberized, crescent-shaped grips Flexgrip(TM) handle with soft grips

Cartridge: Open-architecture cartridge with pivot Open-back, flow-through cartridge built in and single-cartridge docking

Cost: $6.49-$6.69 (razor) $6.79 (four-pack of cartridges) $4.49 (razor) $5.29 (five-pack of cartridges)

An electric challenge to hydraulic steering

July 20, 1998 Design News

AUTOMOTIVE ELECTRONICS

An electric challenge to hydraulic steering

Microelectronics and software make an old concept newly competitive

Geoff Nairn, Contributing Editor


Electric power-assisted steering (EPAS) has tempted automotive engineers since the 1950s. Even so, the promise of smaller, lighter, and more efficient systems never quite matched the low cost and performance of hydraulic power-assisted-steering (HYPAS).

Advances in microelectronics, however, have rekindled interest in EPAS. Motor drive stages, electronic control units, and torque sensors can now be manufactured relatively cheaply. These components, coupled with complex control algorithms implemented in software, can rival or better the performance and functionality of conventional hydraulic steering systems. In addition, software can be fine-tuned to deliver the desired mix of stability, robustness, and steering "feel."

So says Tony Burton, control engineer with automotive component supplier LucasVarity plc (Solihull, England). The company is presently working on an EPAS system that offers a lower component count than HYPAS, is three to five kg lighter than a comparable HYPAS system, and consumes 4 to 5% less fuel. Attached to the steering column, the self-contained unit is said to be easy to install and particularly cost-effective on smaller vehicles.

"There are often considerable difficulties fitting HYPAS to a small car," Burton explains. The LucasVarity system, he estimates, could be installed in four minutes on a production line.

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Control algorithms, implemented in software, help EPAS challenge HYPAS in performance and functionality.

How it works. Operation of the LucasVarity EPAS is straightforward. An optoelectronic sensor measures driver torque applied to the steering wheel. The electronic control unit takes this measurement and, through the control software, drives the motor.

The brushless dc motor generates an additional torque which acts through a reversible gearbox to the steering mechanism, assisting the driver. This assistance torque varies from about 15 Nm in a small "city" car, to 75 Nm in a larger car such as a Ford Taurus, and diminishes with road speed.

14f1648d.gif (12631 bytes)
EPAS optical torque sensor meets reliability, fault tolerance, and electromagnetic compatibility requirements while low enough in cost to mass produce.

A frequent complaint made of HYPAS systems is their tendency to "over assist" the driver at higher speeds. In poorly designed systems, this can result in the vehicle oscillating or "yawing" around the center line as the driver attempts to correct the oversteer.

In the new EPAS system, software allows precise control over steering behavior. Algorithms programmed into the system define speed sensitivity, yaw damping, and steering self-centering. Added algorithms can give steering a "sports" feel or offer light load settings.

A safety relay incorporated into the design improves fault tolerance, while the electronic control unit includes diagnostic functions for fault detection and management. If the system fails, its "fail stop" design cuts all torque assistance and returns the driver to manual steering.

For a torque sensor, LucasVarity incorporates a dual-channel optical device. Its non-contacting design and mechanical simplicity provide system reliability, while the use of optics offers immunity to EM interference.

To operate, two patterned disks mount on either end of the torsion bar separating the steering wheel and steering column. Torque applied to the steering wheel creates a relative movement between the two discs. Light intensity reaching the photodetectors varies in proportion to torque.

Because either detector can be used to measure light intensity and thus torque, the system is redundant. Offset patterns on the two discs, furthermore, allow the software to calculate the steering wheel's relative position and velocity by comparing the two sensor signals.

Motor design. Achieving a smooth, progressive feel at the steering wheel requires a motor with low levels of ripple and cogging torque. LucasVarity, therefore, uses a three-phase inverter to control motor phase currents, and hence torque. An array of power MOSFETS make up the circuitry; pulse width modulation (PWM) regulates switching time and sequence for the MOSFET stages.

Since the power-switching stage encompasses the most complex dynamics of the whole EPAS system, optimization requires computer simulation. Lucas uses the Saber simulator program from U.S. software house Analogy Inc. to analyze alternative PWM strategies, and to model the complex patterns of secondary currents induced when the MOSFET stages are switched.

14f1648e.gif (9175 bytes)
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Low-cost components mean EPAS systems can be engineered to cost the same as HYPAS while offering additional advantages.

The aim, Burton explains, is to ensure smooth control of the switching stages and also reduce the ripple currents fed into the battery harness. "These currents have to be filtered out to protect the electronics in the EPAS control unit. By minimizing the ripple current, we are able to use filter components with lower ripple specifications and, therefore, lower cost."

LucasVarity's Electric Power Assisted Steering system is targeted primarily at the European market where smaller cars dominate and the advantages of EPAS offer the greatest potential. "But there is no reason why the system cannot be scaled up to larger cars," Burton adds. The company claims to have negotiated a development contract with a leading European carmaker which could see EPAS installed on production models in the year 2000.


EPAS prospects, pros and cons

by Anna Kochan, UK

EPAS technology is new to Europe but has been available on small (600 to 800 cc) Japanese cars for more than 10 years. First systems to arrive in Europe were adaptations of Japanese park-assist units, such as the one incorporated in the 1996 Renault Twingo.

Developed in collaboration with the Japanese company Koyo, the Twingo EPAS provides assisted steering up to a speed of 65 km/hr. "EPAS know-how is now being transferred from Japan to France where production of EPAS systems will start within six months," claims Yannick Lacour, director of strategic planning at SMI, the Koyo subsidiary in Irigny (near Lyon, France).

Another Japanese manufacturer bringing EPAS into Europe is NSK. Its systems have been fitted into 1-l Opel Corsas since 1997. NSK EPAS is also likely to be introduced on the 1.2-l version of the Corsa, and is offered as an option on the new Fiat Seicento.

For more powerful vehicles, some manufacturers are starting to develop a hybrid approach to EPAS technology. These are electro-hydraulic steering systems, which use an electric motor to drive the hydraulic pump, rather than driving it off the engine.

As a result, the hydraulic pump runs independently from the engine, and needs only run when power support is required at the steering wheel. It gives a fuel savings of 0.2 litre per 100 km, claims Karl Mauer, Opel spokesman, whose company is adopting a hybrid system on the new Astra being released this year. The suppliers are TRW and Delphi Saginaw.

Many vehicle manufacturers are, however, not satisfied with current EPAS performance. "Right now they don't give the comfort and safety we want to provide our customers with," remarks Marc Boucque, R&D spokesman at PSA. He talks of a "sticking" phenomenon, meaning that the steering wheel does not go naturally back to its original position after it has been turned. However, Boucque expects EPAS performance and cost to reach an acceptable level by 2000 when PSA will incorporate it widely into their models.

Ford, like PSA, is not satisfied with current EPAS performance. "We are not dismissing the technology, but we have evaluated 12 of the systems that are currently being developed or in production and none provided a satisfactory dynamics performance," reports Ulrich Eichhorn, manager, vehicle dynamics, advanced vehicle technology and small and medium car vehicle center, Ford Automotive Operations.

"They feel artificial because they suppress feedback from the road. Vehicle response is not what we would like it to be," he adds. Ford will probably use electro-hydraulic technology as a first step towards EPAS because it works with existing hydraulic systems, Eichhorn indicates.

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Motors/drives

Motion drive catalog provides information on Vector Drives(reg), Servo Drives, and MINT(TM) motion control products. The catalog is divided into sections, the first providing an overview of products available for motion control applications.In addition, MINT motion controllers, operator interfaces, and programming software are introduced. The second section defines MINT technology, and the third details motor controls. Technical data, specifications, dimensions, and other options are provided.

Baldor Electric Co., Box 2400, Fort Smith, AR 72902, FAX (501) 648-5792.

Miniature fittings

Miniature pneumatic fittings feature a leak-tight O-ring face seal design to prevent compressed air losses. Seals are available in Teflon, Viton, Silicone, EPDM, AFLAS, and Buna-N O-ring seals to meet temperature and chemical compatibility requirements. M3, M5, and M6 threaded fittings are available, and applications include semiconductor production machinery, medical equipment, factory automation, among others. Catalog describes miniature O-ring face seal fittings, valves, quick disconnects, tubing, pressure regulators, and cylinders. Specifications, diagrams, and information are provided for each product.

beswick engineering Co. Inc., 2384 Ocean Rd., Greenland, NH 03840, FAX (603) 433-3313.

Safety light barrier

The SAHD safety light barrier defines a safety perimeter to protect operators working with or around dangerous machines. This can involve such working environments as a robotised installation, or access to a handling or automatic palletisation system. Equipped with one, two, or three 20m beams, depending on the variant, the SAHD safety light barrier satisfies European standards EN 50100 and EN 61496, and has been awarded a Type 2 EC examination certificate.

Jay Electronique, 176, rue Lavoisier--BP5, F-38330 Montbonnot St. Martin, France, FAX +33 4 76 41 44 41.

Guest Commentary 7-20-98

July 20, 1998 Design News

GUEST COMMENTARY Exclusive interviews with technology leaders

New opportunities for MCAE

Thomas C. Curry President and Chief Executive Officer The MacNeal-Schwendler Corporation


"Analysis-driven" design, Curry states, is close to a reality at some advanced manufacturers.

Global Design News: What advantages can a specialist company like MSC offer customers that seek a single source for their CAD/CAM/CAE and even PDM needs?

Curry: The answer is in the question: We are "specialists." As much as they may want to be, or even claim to be, the CAD companies can't be everything to everybody. Presently, most of the major CAD vendors are focused on PDM and even ERP because their customers have told them they need better workflow, data management, and integration. They are also providing more CAE as simulation to their design customers who are usually influenced by the engineering analyst. We support this migration of simulation upstream in two ways: We provide tools for the professionals to capture their knowledge and corporate methodology and make it available to their design colleagues, and we "OEM" our technology to companies like UG Solutions and CoCreate for inclusion in their simulation products.

Q: How will industry trends like digital mock-ups and simulation-based design affect the implementation of MCAE in the design process?

A: The use of MCAE in simulation-based design is probably our most exciting area. Our current work centers on a collaborative program, the Robust Design Computation System (RDCS), that uses a parametric version of our MSC/-PATRAN modeler, various solvers including MSC/NASTRAN, as well as deterministic, probabilistic, and Taguchi methods for design scans. We have no doubt that analysis-driven design is close to a reality at some advanced manufacturers and we are collaborating with them in this activity. As for digital mock-ups, they create new needs and opportunities for MCAE. Our aerospace experience, where contractors routinely provide large sub-assemblies for combination and execution by the prime, gives us confidence that MCAE technology is ready to work with digital mock-ups.

Q: Web-enabled CAD, with applications featuring JAVA as the primary programming language, appears to be just around the corner. What strategies does MSC have for the Internet?

A: To date, the best uses of the Web we have seen are in the area of data-management and data communication. We are developing a client-server version of our material properties data management capability we call Enterprise MVISION and we have Web-enabled our pre/-post for results viewing. You can expect a stream of Web utilities from us in the year ahead.

Q: What does MSC say to engineers who may regard MCAE solutions as appropriate for large projects like the design of automobiles and aircraft, but overkill when applied to smaller products such as medical devices or white goods?

A: As to the question of MCAE "overkill" for certain products, we don't see that at all. Any manufacturer concerned with time to market can benefit from simulation in place of prototypes and physical testing. We have both white goods and medical products users in our installed base. In fact, I suspect the highest growth rates in MCAE are to be found in new industries coming to the technology for the first time.

Q: Many analysis products seem to fall into one of two categories: those that are very basic, or complex analysis tools difficult to understand and implement. What are the functionality limits on the lower-end programs?

A: We find that the limits on "low-end programs" are not so much a matter of functionality (linear statics, steady-state heat transfer, etc.) as it is the ability of the user to properly synthesize loads and interpret results. However, there is a great deal more work for the CAE industry to do to automate these tasks.

Q: What kind of training and support does MSC provide to guide, customize, and otherwise manage the analysis activities of design engineers?

A: We have organized by industry (aero, auto, and growth) and expanded our scope from standalone software products to comprehensive solutions to better serve the changing needs of our customers. For example, our new multi-media training program for MSC/PATRAN goes far beyond just instructions on how to use MSC/MSC software--it is a tutorial and finite element analysis theory and application that attacks the very questions that a design engineer has about what possible directions are offered and how to approach engineering problems. In addition, we offer the MSC Institute, on-site training, and hotlines.

Motor

Suppressed GMRG dc motor of the 43 mm motor diameter series is excited by permanent magnets. The armature shaft rotates in both directions in sintered metal sleeve bearings. Two spade connectors with brush holder plate on the rear side are available for connection to the power supply system. Additionally, friction losses in the two-stage spur gear unit have been minimized. Applications include home automation and medical, agricultural, and mechanical engineering.

ITT Automotive Europe GmbH, Presseabteilung, Guerickestrabe 7, D-60488 Frankfurt, Germany, FAX +49 69 7603 3945.

Product News 7-20-98

July 20, 1998 Design News

Product News

Latest and greatest offerings in the engineering marketplace


Loop Calibrator

The mAcal loop calibrator measures mA, V, or flow in a compact package. The calibrator's output range is 0 to 24 mA with an input range of 0 to 24 mA or 0 to 45V. This pocket-sized device also offers stepless setting of the current in the entire measuring range. The loop calibrator features a large LCD display with five characters and status information, and measuring mode resolution is 0.001 mA. The display can shift to reading in percent of full scale and to percent of flow, which means the user can avoid difficult calculations in such instances as flow measurement.
AMETEK Denmark
Gydevang 32-34, DK-3450
Allerod, Denmark
FAX +45 4816 8080.

Motors

Variable-speed drive combines a geared motor and the intelligent frequency inverter 8200 motec, and can be installed without an additional control cabinet or wiring. The frequency inverter construction allows a separate assembly in the machine wall, and the compact geared motor can be integrated into the machine. The speed can be set via a switch/potentiometer unit, a manual terminal, or a RS232 interface. The whole drive can be connected to a superimposed host, using fieldbus modules.
Lenze GmbH & Co. KG
Postfach 10 13 52, D-31763
Hameln, Germany
FAX +49 5154 82 2800.

Chokes

Compact ISDN common-mode chokes surface-mount technology (SMT) are inductive components for telecommunications applications. The chokes are designed in the compact package 5024 and are for SMT. The use of amorphous cores can increase the dc load current up to 0.6A.
Vacuumschmelze GmbH
KB-PM B 2, Dr.
Lehmann, Germany
FAX +49 61 81 38 8 26 29.

Thermometer

Marathon MR1F fiber-optic ratio thermometer measures temperature in hot, hostile environments; in high electromagnetic fields; and in other difficult applications where the line of sight to the target may be obscured. The MR1F consists of a small, rugged optical head; a field-replaceable, fiber-optic cable; and a separate electronics enclosure with built-in user interface. Proprietary signal processing electronics support advanced features such as remote sensor set-up, real-time display of target temperature, and field-calibration software.
Raytek Corp.
Box 1820,
Santa Cruz, CA 95061
FAX (408) 458-1239.

Assemblies

Miniature instrument bearings are assembled with matching LinearRaceTM shaft, guaranteeing a fit of 0.0001 to 0.0003 inch clearance. Smoothness is assured by finishing the working surfaces of the bearings and LinearRace shafts to better than 4 microinches. Precise positioning is enhanced with the virtual elimination of stick/slip by the bearings' low coefficient of dynamic friction. Bearings are available in 1/8, 3/16, and 1/4 inch bore sizes, and their stainless steel and brass construction makes them highly corrosion-resistant. The bearings can be used where lubricants cannot be tolerated, and applications include those requiring extremely precise and smooth motion
Thomson Industries Inc.
2 Channel Dr.
Port Washington, NY 11050
FAX(516) 883-9039.

Bus cables

Bus cables for the INTERBUS are available as system-conform cables, both as remote bus cables as well as installation remote bus cables. The cables are targeted for use for permanent installation, high-flexible applications such as power chains, as well as for outdoor installation and direct burial.
U.I. LAPP GmbH & Co. KG
Schulze Delitzsch-Strabe 25, D-70565
Stuttgart, Germany
FAX +49 7 11 78 38 412.

Switches

Center-off switches are capable of up to 100,000 switching cycles and are watertight in compliance with IP67. The switches measure 13 3 5.5 3 25.5 mm, and feature a contact rating of 5 to 100 mA at 12V and a repeat accuracy of 10 degrees ±5 degrees. When the switch is in its center position, both circuits are open. If the actuator is tipped left or right, the circuit on the opposite side is closed. In the automotive sector, the switch is targeted for lock-barrel interrogation or devices controlled by cams or connecting rods.
Cherry Electrical Products
3600 Sunset Ave.
Waukegan, IL 60087
FAX (847) 360-3566.

Module

IZD Profi 01 module permits wireless connections to any number of PROFIBUS stations. With a range of around 15m, it supports interference-free communications for all PROFIBUS protocols with multiple slaves. The IZD Profi 01 can connect individual stations in one segment and for connecting two segments, which permits communications to be established with changing stations.
Rheinmetall Elektronik AG
Zentralbereich Kommunikation
Postfach 10 42 61, D-40033
Düsseldorf, Germany
FAX +49 211 473 4157.

Sensor

Uproxr proximity sensor is available in a stainless-steel version, and the abrasion-resistant, stainless-steel sensing face can be used in machining applications and other abrasive environments without affecting the sensing integrity of the unit. The Uprox line can detect all types of metals, including steel, copper, aluminum, and brass, at the same sensing range.
TURCK Inc.
3000 Campus Dr.
Minneapolis, MN 55441.

Capacitors and filters

Capacitors and filters suppress conducted RFI and are available in ac and dc versions, with a wide choice of values, performance ratings, and operating currents to facilitate applications matching. These single-line components provide RFI attenuation at frequencies as high as 1 GHz, and are targeted for use in systems with multiple input or output power lines. Available with full-load current ratings from 10 to 200A, all feedthrough components can be used in ambient temperatures from -40 to 60C.
Schaffner Altrac AG
Mühlehaldenstrasse 6, 8953
Dietikon, Switzerland
FAX +41 1 744 61 61.

Power components

The MI family of power components is for use in non-development items and commercial off-the-shelf equipment. The range of modules now includes 11 standard input voltages from 10 to 400V dc and output voltages from 1 to 95V dc. A current share facility, which enables the paralleling of modules, gives a power range of watts to kilowatts.
Vicor
Coliseum Business Centre
Riverside Way, Camberley GU15 3YL
England
FAX +44 1276 681269.

Capacitors

Series PUK motor-run capacitors are UL-recognized to 10,000A fault current, and manufactured in a choice of five different terminations. Featuring a low dissipation factor and high insulation resistance, these long-lasting units have a 250 to 500V ac range, and can be used anywhere one- or three-phase induction motors are employed. Applications include ac ones such as motion control.
Seacor Inc.
123 Woodland Ave.
Westwood, NJ 07675
FAX (201) 664-8544.

Switches

Mechanical safety interlock switches detect the opening of guards, including doors, gates, and/or removable covers, that prevent access to dangerous parts of a machine. The switches also help deter tampering with the guards or the internal machine controls. All safety switches are equipped with positive opening contacts, which open whenever an unsafe condition is detected, causing the machine to automatically shut down.
Sentrol Industrial
12345 S.W. Leveton Dr.
Tualatin, OR 97062
FAX (503) 691-7563.

Converter

The ADS7841 four-channel, 12-bit sampling analog-to-digital converter features a synchronous serial interface. In applications where low power is critical, the ADS7841's power-down mode reduces supply current. This, in combination with high speed and an on-board multiplexer, targets it for use in industrial process control, remote data acquisition, test and measurement, and medical instrumentation.
Burr-Brown Corp.
Box 11400
Tucson, AZ 85734
FAX (520) 746-7401.

SRAMs

Pipelined IDT71V546 and flow-through IDT71V547 ZBT SRAMs are 3.3V devices targeted for use in performance-driven network products such as switches and routers. Operating at 100 MHz, the 71V547 features an 8 ns clock-to-data access time. The pipelined 71V546 operates at 133 MHz and achieves a 4.2 ns clock-to-data access rate. All crucial timing parameters for the SRAMs are referred to to the rising edge of the synchronous clock, which simplifies the design of high-bandwith switching systems.
IDT Europe
Prime House, Barnett Wood Lane
Leatherhead, Surrey, KT22 7DG
England
FAX +44 1372 378851.

Relay

Electronic Timer Relay (ETR) is a 22.5-mm narrow module which allows the user to adjust all timingfunctions via front potentio-meter and DIP switch array. The relay also features a broad time range of 40 msec to 2,500 sec, and "universal" input voltage of 18 to 285V ac/dc. The ETR's industrial housings are DIN-rail-mountable, and single lines are securely connected from a screw connection technology.
Phoenix Contact Inc.
Technical Service Dept., Box 4100
Harrisburg, PA 17111
FAX (717) 944-162