exter Magnetic Technologies was founded as Permag Corporation in 1951 as the FIRST global magnetic materials distributor. Since then, Dexter Magnetic Technologies has grown to become the largest specialized magnetics distributor in the world, servicing all major market segments including medical, oil & gas, mil/aero, semiconductor and more. Dexter’s extensive inventory of ferrite cores, powder cores, amorphous cores, bobbins, thermistors, and specialty wire offers design engineers opportunities to design their product using off the shelf components. Dexter’s machining capabilities and their unique relationship with their vendors offers customers cost effective means for small volume custom cores through large scale production. After 65 years, Dexter continues to focus on what the customer needs, STANDARD PRODUCT, VALUE ADDED SERVICES, UNIQUE NEW PRODUCT.

STANDARD PRODUCT

Dexter’s is an authorized distributor for all the leaders in the magnetics industry.

Ferrite Cores: Ferrites are ceramic, homogeneous materials composed of various oxides with iron oxide as their main constituent. Depending on the application, there are two types of ferrite core material. Manganese-Zinc ferrite (MnZn) is used in applications requiring higher permeability and saturation levels. These power materials are generally used for high frequency transformer applications - important characteristics being high flux density and/or low core losses. Nickel-Zinc ferrite (NiZn) is used in applications needing higher resistivity and is more suitable for frequencies above 1 MHz. Applications are EMC, filtering, power, wireless transfer of power, etc. Cores can also be classified by shape: Toroidal cores, U core, E cores, I cores, Pot cores, cylindrical cores, etc. Core geometries can be modified by machining to meet specific magnetic and mechanical requirements. Core gapping, Toroidal slotting and custom machining available.

Manufacturers Represented:
Fair-Rite
Ferroxcube
Magnetics, Inc.
EPCOS/TDK
National Magnetics
Ferronics
ACME

Powder Cores: Powder Core products are distributed air gap cores primarily used in power inductor applications, specifically in switched-mode power supply (SMPS) output filters, also known as DC inductors. Other power applications include differential inductors, boost inductors, buck inductors and flyback transformers. Characteristics of Powder Core materials are high resistivity, low hysteresis and eddy current losses and excellent inductance stability under both DC and AC conditions. In addition, Powder Core materials are not pressed with an organic binder, therefore, there is no thermal aging.

Common names: MPP, Kool Mu®, High Flux, XFlux®, AmoFlux®

Manufacturers Represented: Magnetics, Inc.

Amorphous & Nanocrystalline Cores: Amorphous metals are produced by using a rapid solidification technology where molten metal is cast into thin solid ribbons by cooling at a rate of one million degrees C/sec. Amorphous magnetic metal has high permeability due to no crystalline magnetic anisotropy allowing smaller, lighter and more energy efficient designs in many high frequency applications for inverters, adjustable speed drives and power supplies. Due to the material having no crystalline magnetic anisotropy, amorphous magnetic metal has high permeability which makes it an ideal option for applications in the alternative energy sector. Amorphous iron (Metglas®) and nanocrystalline (FINEMET®) work well in mag amp and high efficient power applications while amorphous cobalt (Toshiba) works well in suppression devices.

Manufacturers Represented:
Toshiba:

AMOBEADS®
SPIKE KILLER®

Hitachi Metals:

FINEMET®
Metglas ®

Bobbins & Accessories: Bobbins, also known as coil formers, are used for efficient winding and termination of magnetic components. Dexter provides precision plastic injection moldings for use in electrical, automotive and medical sectors. In addition to the standard bobbin offerings, Dexter is able to configure customizations, including pin modifications, higher and lower profiles and custom stack heights. More than half of the products Dexter delivers are custom designs specific to application requirements. Dexter also supplies mounting clamps (clips), toroid mounts and toroid headers.

Manufacturers Represented: Miles-Platts
Magnetics, Inc.
EPCOS
Ferroxcube

VALUE ADDED SERVICES

Dexter Magnetic Technologies offers many value added services to our abundant inventory including complete machining. From standard gaps to complete new designs from block stock, Dexter can machine ferrites to exacting standards. Dexter also can test, sort, fabricate, assemble and Kanban to meet your needs.

Engineering & Design Assistance
Up Screen
Inductance Testing
Special Packaging
Custom Fabrication
System Assembly
Inventory Management
Material Warehousing
Bar Coding
Bag and Tag
Coating
Core Gapping
Toroid Slotting
ISO Capabilities

UNIQUE NEW PRODUCT

Dexter Magnetic Technologies has taken the next step with our customers, turning from a supplier into a true partner with the development of new products into the market. Over the last few years, Dexter has assisted in the creation of many new products including:

StackPack – This unique product, developed with TDK/EPCOS is designed to allow engineers to easily and cost effectively create their own “custom” cores for HV applications. Consisting of round legs, corners and spacers parts, customers can optimize their windows for creepage and clearance and not have to pay for excessive machining costs.

AMCC Cores and Bobbins – When Hitachi decided to expand their distribution network, Dexter stepped up to offer complete stocking on AMCC (AMorphous Cut Cores) as well as tooled bobbins for the parts through Miles Platts. This combination resolved historic issues of not being able to get product, as well as inconsistencies of bobbins through uncontrolled sources.

Bobbin for 3” Single Phase Laminations – Working with Miles Platts, Dexter has developed bobbins for larger single phase laminations, allowing cost effective molded product and multiple stack heights. This unique bobbin allows a designer to get the benefit of a bobbin wound product (over a core tube) and get the ability to modify his core stack height from 2” to 6” in ½” increments.

Finemet Cores - Dexter is the ONLY distributor that carries a full line of Hitachi Finemet (Nanocrystalline) cores. These cores, designed for line noise suppression, reduction of common mode noise, and high permeability applications come in various toroidal sizes.

Single, Double and Triple Stack Bobbins – board space is at a premium and power supply manufacturers are going taller in their designs, rather than wider. Dexter, along with Miles Platts has developed double and triple stack bobbins for E65, E70 and E80 cores (ferrites and Kool Mu) to help reduce manufacturing time.

Provided by Charles R. Wild, Business Manager Specialized Electronic Products, Dexter Magnetic Technologies

Leveraging decades of DC power engineering expertise in the telecommunications industry, Emerson Network Power has designed a unique and powerful energy solution for data rack applications. Inspired by the Open Compute Project, the modular NetSure™ 12V DC Power System delivers industry-leading power density and local energy storage ideally suited for scalable and high-performance computing applications.

This highly configurable 12V system is scalable from 250 amps to 6000 amps and utilizes high efficiency switch mode rectifiers as well as lithium-ion battery backup units (BBUs), both rated at 3000 watts. Each 3U shelf accommodates up to nine power conversion units that can be configured with any combination of rectifiers or BBUs to support specific IT loads and stored energy needs. A System Control Card (SCC) controls and monitors the rectifiers and BBUs while communicating to the rack management system.

Net Sure 12V DC Power Shelf with Six Rectifiers, Three BBUs and One SCC

The power system is designed to fit into a standard 19” EIA rack or 21” Open Rack and allows up to three power shelves in parallel for a maximum system capacity of 72,000 watts (6000 A) at 12V DC. Location of the power shelf or shelves within the rack is flexible and can be configured into single, dual or triple power zones. The power shelf also allows for various AC input configurations and can accommodate up to three inputs of either single-phase or three-phase AC.

Utilizing the lithium-ion Battery Backup Units (BBUs) eliminates the need to have an end-of-row or separate room filled with AC Uninterruptible Power Systems (UPSs), freeing up floor space for future capacity needs. This also increases overall system efficiency by reducing the number of power conversion steps in the network. The design and flexibility of the 12V DC power system allows it to be configured to solve issues such as stranded capacity and branch circuit limitations. If traditional AC UPS systems are employed, users can still capitalize on several advantages of the centralized 12V DC distribution.

Penguin Computing recently recognized the density advantages of the NetSure 12V DC Power System and turned to Emerson to architect a power solution for their HPC clusters. The resulting design helped them land a substantial national deal and continues to support the validity of open hardware and 12V DC architectures. Penguin Computing’s Tundra ES system builds upon the form factors that Facebook introduced with Open Compute, adapting them for HPC with the aim of increased density, efficiency and serviceability. While the Penguin Computing solution did not include the use of BBUs, the high power density of the NetSure 12V DC Power System enabled them to essentially double the standard rack density and accommodate up to 96 nodes per rack with the associated shared power infrastructure and fabric/networking switches.

To increase system efficiency and availability, advanced monitoring features like eco-mode technology and power boost functionality are built into the NetSure 12V DC Power System. Eco-mode enables rectifiers to operate at their peak efficiency by selectively enabling and disabling them based on IT load. The power boost feature caps power consumption from the source (utility, grid, generator, etc.). Rectifier output power can be limited to a preset value and the BBUs provide additional power as the peak load demands.

The NetSure 12V DC Power System meets the requirements of UL 60950-1, Standard for Information Technology Equipment, and is UL Recognized as a power supply for use in Telephone, Electronic Data Processing or Information Processing Equipment. Furthermore, it is constructed without the use of any hazardous substances or chemicals per RoHS and REACH specifications.

To learn more about this innovative solution from Emerson Network Power, visit http://www.emersonnetworkpower.com/en-US/Products/DCPower/ensys_12VDCSystems/Pages/NetSure-12V-DC-Power-Systems.aspx.

Provided by Mike F. Smith, DC Power Product Manager and Ben Pruitt, Director of Technical Sales, Emerson Network Power

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