Connector system, offered in 3 to 30 circuits, is available for straight PCB, right angle PCB, panel or cable mountings, offering maximum design flexibility.
Anderson Power Products (APP), a leader in high power interconnect solutions, offers the high density PowerMod connector family. The connector system, offered in 3 to 30 circuits, is available for straight PCB, right angle PCB, panel or cable mountings, offering maximum design flexibility for a variety of system packaging. The high performance PowerMod family is rated for 30A and features mechanical polarized UL94V-O housings for proper circuit mating.

Additionally, the connectors have up to four sequential pin mating options available for mate-first/break-last and make-last/break-first circuits.

The APP PowerMod design offers stainless steel positive retention latches and optional back shells that provide additional safety and security for the user.

APP PowerMod connectors are available in 13 different sizes: single row 3, 4, 6 and 8 circuit, two row 6, 8, 12 and 16 circuit, and third row 9, 12, 18, 24, and 30 circuit connectors.

In addition, the connectors are UL and TUV recognised and CSA certified.

* About Anderson Power Products - Anderson Power Products is a leader in developing high quality, low cost, power interconnect solutions for several industries, including: Back Up Power Systems, Electrical Recreational Vehicles, UPS Systems, Telecommunications and High-Technology Devices.

Headquartered in Sterling, Massachusetts, USA, Anderson Power Product's facility is ISO 9001:2000 certified and uses automated manufacturing to offer uncompromising quality.

In addition, APP operates a manufacturing and assembly facility in Fermoy, Ireland to provide support for their European customers, as well as three Asia Pacific facilities: Shenzhen, China, Shatin Hong Kong and Taichung City 407, Taiwan (R O C).

Sealing boots feature a soft feel to facilitate prehension and provide stringent protection to IP67; i e, immersion under one meter water for 30 minutes without water ingress.
APEM Components, a leading manufacturer of high quality miniature and industrial switches, introduces two new sealing boots to its extensive line of durable sealing boots for switches. These unique sealing boots feature a soft feel to facilitate prehension and provide stringent protection to IP67; i.e, immersion under one meter water for 30 minutes without water ingress. Recommended applications include optical line termination units, control handles, vehicular intercom systems, and talk switches.

These new sealing boots are designed for front panel mounting next to joysticks.

The smaller of the two, U2252, can be mounted on the standard levers of APEM's 12000, 3500, 3600 and 600 toggle switches, while the larger one, U2197, is intended for APEM's X2243 long lever of the 3600 and 600 series.

These sealing boots can be fitted to more than 10,000 switch part numbers.

Each boot is supplied with a sealing ring or washer to provide for maximum protection.

Neoprene models are available in black, and silicon models are offered in a wide variety of colors, such as black, white, green, red, and transparent.

Each color represents a particular function: red signals danger, green can indicate priority or absence of danger, white offers better visibility in semi-darkness, and transparent boots allow visual access to the marking, color or position of the actuator on which they are mounted.

Additional options include nickel-plated or matte black finished brass.

* About APEM - since 1952, APEM has been a leader in the manufacturing of high quality miniature and industrial switches.

Offering one of the broadest product lines on the market, APEM's switch line includes pushbuttons, rockers, slides, DIPs, rotaries, tacts, keylocks, pushwheels and snap-action switches.

APEM also provides a wide range of industrial controls, membrane switches, panels, and keypads.

Is enough consideration given to the protection rating of circuitry and switchgear enclosures? Graham Fox looks at the areas of an enclosure that can make the difference.
Protecting circuitry, electrical connections, wiring for displays, manual switch gear, sensors and breakers are the basic functions of an electrical enclosure, but is enough consideration given to the protection rating of that enclosure? The difference between an electrical enclosure offering IP54 and IP65 protection can make the difference between a well specified junction box that meets cost pressure and protection requirements and a failed installation due to moisture ingress, condensation or dust build up in a relatively normal working environment. The IP rating of an enclosure is dictated not only by the enclosure itself, but also by its fixing method, lid sealing and cable entries.

After the 'IP' (Ingress Protection) part of an enclosures protection rating, the first number equates to the protection offered by the box as regards solid objects from screwdrivers and fingers through to fine particulate dust.

Most plastics and metal enclosures offer a 4, 5 or 6 rating (objects under 1mm diameter), a 4 is suitable for a basic wiring junction protected by a wall, ceiling, cabinet or similar in a dry environment, but a 5 or 6 is the preferred option should the enclosure be exposed in any way and this covers most industrial applications where the box can be seen or is accessible as part of routine operation or maintenance.

Pressed metal enclosures offer the poorest protection and are generally a 4, cast (usually aluminium) and most polystyrene and virtually all polycarbonate enclosures fall into the 5 or 6 categories.

There is a third number that refers to impact protection, but is not often quoted; the second number is where a decision has to be made and where several clear variables come in to play: When mounting an enclosure inside a cabinet, fixing to a machine wall, a building wall or a post, the method of attachment can either maintain or instantly downgrade the IP rating of the enclosure assembly.

For example, in an industrial environment that may include water sprays, wash downs or atmospheric moisture, a screw fixed IP65 enclosure with IP68 cable glands can be rendered IP64 or lower simply by not employing grommets between the screw or bolt heads and the enclosure wall when fixing the enclosure in place.

Fixing to posts or uneven surfaces is more problematic and an external fixing of some sort such as cable-tie brackets can be very useful.

Gluing or gun applied sealant is also an option.

The lid sealing of an enclosure is the next major element to affect the sealing, basic 'click' fit lids are generally IP54 or lower.

Pressed metal enclosures are the worst, allowing either dust or moisture in reasonably easily, whereas plastic 'click' fit enclosures generally offer IP54, which provides limited protection from both dust ingress and liquids.

Cast metal enclosures or industrial plastics such as moulded polystyrene and tougher polycarbonate generally offer much higher levels of protection.

Lid fitment of IP54 and above generally requires an additional compressible seal to achieve higher protection.

Machine applied polymer seals are generally more reliable than gasket types as they are not prone to movement during fixing and a seal that runs inside the lid fixing screws is normally required for IP65 and above.

Cable entries are present in virtually all sealed enclosures offering a significant IP rating; they vary from basic cable clamps through to independently rated waterproof cable glands.

Basic cable clamps and open holes offer some protection, but where moisture is present to any degree the cable entry must offer a complete seal around the cable sheath.

Recent developments in push-fit seals have seen both the grommet type and the moulded-in version offering high ratings up to IP65 in some instances, providing protection from drips to low power water sprays and suitable for general above ground outdoor applications.

Underground use, temporary immersion, wash downs in the food and processing industries or exposure to the sea requires IP65 and above, this generally requires cable glands fixed to the enclosure wall and high quality compression seals.

An IP65 rated box is not IP65 when the cable entries do not offer the same protection.

The harmful effects of both dust and moisture to sensitive equipment, circuitry and switchgear can cause electrical shorting, component corrosion and greatly reduced reliability hence proper sealing is crucial.

Other considerations such as ambient atmospheric moisture combined with large temperature fluctuations can also cause condensation problems, in situations where this situation is likely, it always pays to fit breather valves (or grommets) to allow the enclosure humidity and pressure to equalise without compromising the intended IP rating.

Advice on specifying enclosure ratings, what is appropriate for any given application and how to avoid compromising the intended IP rating should be provided by all dedicated enclosure suppliers and specialists, in addition to carrying a range of enclosure types and accessories to provide the ideal solution no matter what the challenge.

EAO is offering what it described as crisp blue and white LED illumination options for its Series 84 range of pushbutton switches.
EAO is offering what it described as crisp blue and white LED illumination options for its Series 84 range of pushbutton switches. The options are supplementary to the current options of single-chip or multi-chip LEDs in red, yellow and green. The low profile, flush mount illuminated Series 84 pushbuttons are available in either aluminum or plastic construction and in a standard 22.5mm cut out.

They are said to be robust, benefiting from protection up to IP67.

Complementing EAO's Series 84 range, the illuminated pushbuttons can be connected by either 300mm ribbon cable or plug-in terminals, which enables the pushbuttons to be safely adapted to PCBs of different heights.

A double-blade, slow make switching system ensures pleasing tactile operation and guarantees reliable switching, even of very light loads.

With a maximum rating of 42VAC/DC, 100mA, the switches are suitable for PLC level signals, said EAO.

Featuring a minimum low back panel depth and being 2.0mm from the front, the ergonomic design of EAO's Series 84 pushbuttons also makes them appropriate for contemporary control panel designs where space is restricted.

Ease of working and accessibility are major factors in the installation of electrical systems in enclosures, which is why an electrical cabinet supplier says simple door removal is important.
Ease of working and accessibility are major factors in the installation of electrical systems in enclosures. Consequently EMKA (UK), as the premier suppliers of enclosure furniture to specialist manufacturers has made a point of featuring simple door removal in the design and fitment of their many ranges of hinge styles. The comprehensive EMKA programme covers many standard types for prominent (lay-on) doors or flush fit doors.

For example concealed hinges are available to suit both door types with a selection of lift off features.

Similarly with external hinges for traditional prominent doors.

Door removal by simple lift off or pin removal is a great advantage in the workshop when instrument holes have to be punched in doors or the ability to lay a door face down can speed wiring of graphics panels, meters, pushbuttons etc.

Hinges which come apart in this way are available in many styles - for example weld-in with lift out pin or external torpedo type either for weld-on or bolt-on fitment.

Yet others have the added security of removable circlips on the hinge pin.

Responding as they do, to customer demand, EMKA provide many fixing options with each half screwed on, one half screwed/one half welded, both halves welded or perhaps most cleverly of all a simple drop-in concealed pin fix so that no tools are required to fit or remove the hinge at all, even further reducing assembly time.

Materials of these clever designs are predominately zinc die (finished in black or chrome) with increasing interest in moulded black polyamide.

Stainless steel - especially specified for food industry or unusually corrosive applications, is also an option for many lift-off hinge types.

Medium sized cable manufacturing group has much experience in the design and production of power, control, electronics, machine tool and custom cables for low voltage applications.
With a shrinking base of indigenous cable producers, In2Connect is helping to alleviate UK cable supply problems by introducing for the first time to engineers, OEM buyers and distributors the extensive products and services of G C E Cavi Elettrici of Italy. G C E Cavi Elettrici is a medium sized cable manufacturing group with much experience in the design and production of those power, control, electronics, machine tool and custom cables for low voltage applications popular in the UK whilst In2Connect is a company with over 40 years experience of UK cable and interconnect manufacture. Together they provide the highest levels of service and quality associated with experienced staff, new production plant and quality assurance to ISO 9001 and holds numerous approvals and certification by VDE, IMQ, HAR and DESINA.

As well as european standard cables, UL and CSA listed, approved and certified types are manufactured.

As a major supplier to the European machine tool industry the G C E factories support the DESINA concept of decentralized cabling as a basis for factory standards.

G C E has already adopted the European directive on the use of hazardous substances, EU RoHS Directive 2002/95/EC as a standard across all product ranges.

Cable insulating and sheathing materials used are many and various ranging from PVC to TPR and PUR, and braided copper and/or Aluminium foil screens.

Control and power cables: * PVC control cables 300/500V * YSLYZ * YSLCYZ * YSLYCYZ * H05VV-F * LSF control cables with enhanced flame retardance 300/500V.

* UV resistant PVC control cables 0.6/1kV.

* Oil resistant PVC control cables 300/500V.

* Flame retardant non corrosive control cables 300/500V.

* polyurethane control cables 300/500V.

* Zero halogen PUR control cables 300/500V - 450/750V.

Electronics cables: * PVC Electronics cables.

* LiYY.

* LiYC.

*LiYCY paired.

* PVC electronics cables, individually screened pairs.

* FRNC electronics cables.

* Interface cables for industrial us.e * UL/CSA listed PVC electronics cables.

* UL/CSA listed 'Low Capacitance' PVC electronics cables.

Trailing cables: * Trailing cables for cable chains 300V - 300/500V - 600V - 0.6/1kV.

Cables for Factory Automation: * Heidenhain measuring systems, Bosch controls, Indramat controls and tachymeter systems, Siemens controls, Sinumerik cabling, Baumuller controls and Berger Lahr motion controls.

* Sensor actuator cables for M12 connectors.

* Valve plug cables for M12 connectors.

* Composite cables for M12 actuator sensor boxes.

* Power and Servo cables.

Special copper: * Braided square copper ropes.

* Circular section plaited copper.

* Multi-wired copper strands.

Schneider Electric will present its offers for material recycling facilities (MRF) and energy from waste (EFW) sites on stand 772 at RWM 2005 at the NEC, Birmingham on 13 - 15 September 2005.
Schneider Electric offers free audits Schneider Electric will present its offers for material recycling facilities (MRF) and energy from waste (EFW) sites on stand 772 at RWM 2005 at the NEC, Birmingham on 13 - 15 September 2005. The company's comprehensive range of electrical and control products and services enables end users to improve processes, reduce energy consumption, reduce costs and lessen the environmental impact of their plants. With this in mind, at RWM 2005 Schneider Electric will be offering customers the opportunity to win either a power quality or an energy audit.

These audits will investigate either the condition of the site electrical supply or the energy efficiency of the site and process.

By providing users with detailed information about the quality and consumption of energy on site, potential improvements could be identified, leading to a reduction in energy costs and improvement in site efficiency.

Schneider Electric's engineering team has extensive experience in the waste and recycling industry and works with major plant operators throughout the world.

The range of Schneider Electric products for use in the waste and recycling industry is extremely broad.

Through its world class brands, Merlin Gerin, Square D and Telemecanique, Schneider Electric offers a range of products from simple pushbuttons through to process controllers, and from energy meters to complete medium voltage electrical systems.

Small, low cost, plastics bodied, non-contact, infrared sensors, which require no external power source, monitor electrical equipment temperature inside the cabinets.
Temperature is one of the best indicators of a fault or malfunction in virtually all electrical or mechanical equipment. However, key electrical switchgear has proved very difficult to monitor, being inaccessible within metal enclosures. Over the last decade, the accepted preventative method of reducing the risk of key electrical switchgear failure, has been periodic thermal imaging, but it is not the ideal solution.

Firstly, thermal imaging inspections are normally only periodic, (typically once or twice per year), due to the high costs/time involved.

Secondly, thermal imaging is carried out externally to the switchgear enclosure, thus only components immediately adjacent to the external panel can be inspected.

Thermal 'windows' improve the situation, but still require direct line of sight to the target.

The answer is to have a predictive system, actually inside, directly and continuously monitoring all key components.

ExerTherm is a unique system, based on patented, small, low cost, plastic bodied, non-contact, infrared sensors, which required no external power source, so allowing the sensor to be placed inside the enclosure, to continuously monitor any component, irrespective of location.

Because the non contact infrared sensors require no power, (just like a normal contact thermocouple), they do not require an amplifier.

As a result they have lifetime calibration.

All other IR sensors require power, requiring panels to be opened regularly and sensors accessed for re-calibration.

ExerTherm sensors also have unsurpassed reliability, with over 1,000 year MTBF, and require no maintenance.

Put all these features together, and it means a true 'fit and forget' product Though originally designed to monitor electrical switchgear, virtually all key plant (anything which increases or decreases in heat as a symptom of fault or malfunction), can also be continually monitored Sensors are linked back via data acquisition cards to a PC or server, to provide on-going trend analysis, graphs and reports.

Further protection is provided via two separate alarm levels per sensor (warning and alarm), which automatically activate in the event of pre-set temperature levels being exceeded.

Other key features of the ExerTherm system include: suitable for new, retro-fit/expansion, easy and inexpensive integration with over 400 BMS/bus protocols, available via LAN, WAN, internet, intranet etc This new technology which provides the next significant step forward in reducing the risk of major failures in critical power or plant equipment, has already been successfully installed with many major blue chip organisations in, financial services, media, telecommunications, computer data centres, shipping, and large-scale manufacturing.

SOW coiled cords feature a highly-mobile and extremely durable Neoprene jacket and comply with RoHS and WEEE regulations for use in industrial equipment and tooling.
SOW rated coiled cords are designed for heavy-duty SOW coiled cords feature a highly-mobile and extremely durable Neoprene jacket and comply with RoHS and WEEE regulations for use in industrial equipment and tooling. Whitney Blake Company, the leader in interconnect solutions, offers its SOW rated coiled cords, designed for heavy-duty applications. Used throughout the wire and cable industry, Whitney Blake's SOW coiled cords comply with RoHS and WEEE regulations.

These rugged cords are ideal for use in industrial equipment, production line tools, material handling equipment, commercial vehicles, control equipment, and instrumentation and testing devices used by many Fortune 500 OEMs.

Whitney Blake's SOW coiled cords feature a highly-mobile and extremely durable Neoprene jacket.

These cords have an extension length of 10 to 20ft (2 to 4ft retracted) and are available in 12AWG through 18AWG.

These SOW cords reach a maximum of 600V and provide optimum retractile properties over a broad temperature range, giving the user the greater range of motion needed for demanding environments.

All cords are UL-listed and CSA-certified.

Its broad range of in-stock coiled cords are available for immediate delivery, however, Whitney Blake can develop custom-designed cords to meet most any requirement.

Various wire gauges and conductor counts are also available.

* About Whitney Blake Company - Whitney Blake Company is an industry leader in the design and manufacture of custom cable, cable assemblies and custom over molds for high performance, high flex applications.

Its services include contract assembly and plastic mold injection utilising its Mexican manufacturing capabilities.

Its cable assemblies are used by OEMs as a component in the manufacture of a variety of commercial and military communications, transportation, electronic data processing, medical electronics, durable goods and other equipment.

Novel, rugged, handheld, electrical tester determines 3-phase wiring rotation as well as contact-free indication of the direction of rotation of synchronous and asynchronous motors.
Fluke has introduced another rugged, handheld, electrical T and M product for professional electricians and industrial maintenance applications which is particularly useful during installation and servicing. The unique new tester determines 3-phase wiring rotation as well as contact-free indication of the direction of rotation of synchronous and asynchronous motors. The new Fluke 9062 Motor and Phase Rotation Indicator offers rapid indications for professionals.

The test probes supplied offer a variable clamping range for safe contact, even in industrial sockets, to indicate the direction of 3-phase rotation.

Particularly useful for 3-phase motors which are running but whose shafts are not easily visible, the 9062 provides direction indication without the connection of leads.

The Fluke 9062 measures just 22cm x 16.5cm x 6.5cm and weighs around 650g.

It is available from Fluke authorised wholesalers and distributors at a recommended price of GBP 105.

Additions to a general purpose, long-life, relay family feature optional green, non-polarised LED that provides enhanced visibility of power status from multiple directions.
IDEC is pleased to introduce the new RJ and RQ series to its General Purpose relay family. Boasting a long operational life and the industry's leading contact rating within this form factor, these relays ensure reliable performance when you need it. With a long operational life of 200K cycles at full AC resistive load, the RJ relay performs beyond expectations when put to the test.

Both the RJ and RQ series have contact ratings of 12A (SPDT) and 8A (DPDT).

In addition, the RQ series has a high-capacity 16A (SPDT) model available.

But what really makes the RJ relay outshine other relays is our attention to quality and design details.

An optional green, non-polarised LED is available providing enhanced visibility of power status from multiple directions.

In fact, IDEC uses a unique light guide to make this status indicator brighter and more noticeable.

Not only that, but the compact RJ blade relay is the perfect solution for saving space in your crowded control panel when used with its SJ socket.

With a compact profile of 15.5mm total DIN width, using a RJ relay and SJ socket will reduce your required DIN width mounting by 30 percent when compared to standard 2-pole relays.

The low profile RQ PCB relay also provides a high-quality relay for your printed circuit board relay applications.

With industry standard 3.5mm and 5mm pin terminal separation, this relay is only 15.6 mm in height, 12.6mm in width and 29.0 mm in depth.

Size equals value giving you a compact solution for your boards, while maintaining the contact ratings you expect from IDEC.

The RJ relay's socket, the SJ series, includes multiple features for ease-of-use.

The SJ socket can be DIN rail or panel mounted and comes with IEC finger-safe terminals, where the coil and contact terminals are on opposite sides of the socket.

Both come with a unique built-in lever for securing the relay.

This same lever will easily and quickly allow you to release and 'pop' out the relay for quick replacement.

An IEC socket is also available for the RQ PCB relay.

The SQ socket can be DIN rail and panel mounted, comes with a simple locking and release lever, marking strip and has the capability for plug-in LED modules.

IDEC RJ relays are UL recognized, CSA certified, VDE approved and CE marked in compliance with IEC 61810-1.

RQ relays are UL and c-UL recognized, TUV approved and CE marked.

Improve your control panel in a flash by replacing Omron's G2R series, Finder's 44 Series and Allen-Bradley's 700-HK series with the RJ or RQ relays, as direct plug-in replacements.

* About IDEC - IDEC designs and manufactures control automation products that are sold to original equipment manufacturers.

With products that direct processes and systems, IDEC components are used in a wide variety of applications.

Part of a global network, IDEC's parent company IDEC Izumi is known worldwide for its quality and reliability in the pushbutton industry.

IDEC Izumi has been in business for over half a century.

With a strong presence in Asia, North America, Central and South America, Australia and Europe, IDEC products are found all over the world.

Phoenix Electronics has introduced a new gasket that will reduce assembly time when using the Harting B series housings.
Phoenix Electronics has introduced a new gasket that will reduce assembly time when using the Harting B series housings. The gasket's innovative design allows it to cling to the housing during assembly, thereby reducing the assembly time and cost. The product is IP65 rated and works over the industrial temperature range of -40 degrees C to 125 degrees C.

To facilitate the new gasket design, a slight modification has been made to the Harting HAN B housings.

Samples and data on the product are available from Phoenix Electronics, which is an engineering distributor of Harting products and as such, is able to provide technical backup and stock availability on all of the Harting product range.

A new 22-page guide on EMC filters and their application has been just been published by REO.
A new 22-page guide on EMC filters and their application has been just been published by REO. It is available free on request or can be downloaded from the company's website. Topics covered include a definition of EMC filters and their design, typical filter components, choke design and issues affecting filter performance.

Selecting an EMC filter based upon typical test house protocols does not guarantee the connected product will not cause (or suffer) problems in the field due to conducted emissions (or immunity).

According to REO UK, such tests only provide a rudimentary method of assessing the relative merits of one filter range against another.

They do not provide an effective means of selecting a filter with the intention of ensuring compliance with EMC emission.

The test data should reflect a supply and load impedance mismatch, which is more typical of everyday operating conditions.

Furthermore, a better performance does not necessarily depend on the use of higher quality components, multiple stages and inherent, additional cost but it is more a question of careful design and manufacture.

With the electromagnetic (EM) spectrum becoming ever more densely populated due to the rapidly growing number of EM emitting devices (intentional and unintentional), that can both suffer from and generate EM noise, the selection of a correct filter for EMC (electromagnetic compatibility) has never been more important, said the company.

The Stix family of compact hand-held meters from Metrix Electronics offers a choice of instruments designed to measure a wide range of electrical and environmental signals.
The Stix family of compact hand-held meters from Metrix Electronics offers a choice of instruments designed to measure a wide range of electrical and environmental signals. Each instrument in the range is housed in a distinctive yellow case measuring only 170mm x 44 x 40mm. Common features include simple-to-use push button controls and a 3.5 digital backlit LCD screen.

All models meet EN61010-1 safety standards and are supplied complete with fabric belt-loop carrying case and batteries.

The Stix 67 Digital Multimeter incorporates full auto-ranging and data hold facilities and provides quick and accurate measurement of voltages, resistances, dioide and continuity in all types of electrical systems, claimed Metrix.

The model is currently available ex-stock from Metrix Electronics, with discounts available for bulk orders.

The Stix range also includes instruments specifically designed for measuring light intensity, atmospheric humidity, ambient temperature, thermocouple temperatures and surface temperatures using infrared sensing technology.

Stix Light Meters Models 630 and 631 are also currently available ex-stock from Metrix Electronics.

Datasheets and prices are available from the Metrix Electronics website.

Measuring just 65 x 65 x 57mm, a compact, polycarbonate enclosure is designed to be used as an accessory for EAO's low-profile Series 84 illuminated 22.5mm emergency-stop button.
A compact, Emergency-stop box is among the new range of polycarbonate enclosures introduced by EAO, the experts in Human Machine Interfaces. Measuring just 65 x 65 x 57mm, the compact enclosure is designed to be used as an accessory for EAO's low-profile Series 84 illuminated 22.5mm Emergency-stop button. It is available in grey with a bright yellow top.

There are a total of 11 new enclosures within the range, including options for mounting one, two, three, four or six 22.5mm switches.

There is also a larger 94 x 94 x 81mm Emergency-stop box for applications requiring a more prominent button.

In addition to Emergency-stop buttons, EAO offers a wide range of 22.5mm switches for use with these enclosures, including illuminated pushbuttons, indicators and pilot lights, and key-locks, rotary switches and multi-position lever/selector switches.

Most 22.5 products are available in either flush- or raised-mounting styles.

All EAO's 22.5mm switches and their accessories are built for demanding environments within process control, instrumentation and machinery, and lifting and handling industries.

Low voltage limiters combine a metal oxide surge arrester without gaps and a thyristor-based low voltage limiter ensure effective protection of personnel and equipment in DC traction systems.
ABB's new generation HVL (hybrid voltage limiter) low voltage limiters, that combine a MO (metal oxide) surge arrester without gaps and a thyristor-based low voltage limiter, have been developed to ensure effective protection of personnel and equipment in DC traction systems. They fulfil all the requirements for voltage limitation while reducing touch potentials to harmless levels. * The need for low voltage limiters - in DC traction systems stray currents can flow in the ground from the rails to other metallic structures (such as drainpipes, bridges, fences and so on) where they can cause corrosion and considerable erosion of the metal.

To avoid this problem, it is common practice not to have direct earthing of the rails where possible.

However, this can lead to unacceptable potential rises and too high touch voltages, both in normal train operation but especially in the case of a failure such as a broken overhead line or derailed pantograph.

In such installations, protection for personnel has to be provided by the use of low voltage limiters (LVL).

* The need for over voltage protection - in addition to the touch voltages caused by failure in the supply system, impulse over voltages caused by lightning or switching can occur on the rails.

These impulse over voltages can travel along the rails to the substations and damage the electrical equipment.

So in addition to personnel protection, reliable over voltage protection has to be provided for the electrical systems.

* The ABB solution - two devices in one - ABB's solution has been to develop a new device - the HVL (hybrid voltage limiter).

The HVL combines the required personnel protection against touch voltages with protection of electrical equipment against lightning over voltages.

The HVL contains a metal oxide (MO) varistor in parallel to two anti-parallel connected thyristors.

Over voltages generated by lightning with a duration of some 10 microseconds are limited by the MO-varistor.

Over voltages with a time duration of 0.4 milliseconds and longer are limited by the thyristors to a voltage below 3V.

The HVL is completely encased in silicon.

* About ABB - ABB is a leader in power and automation technologies that enable utility and industry customers to improve performance while lowering environmental impact.

The ABB Group of companies operates in around 100 countries and employs about 104,000 people.