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Glossary of terms for the magnetics industry Select a letter: A-B-C-D-E-F-G-H-I-J-K-L-M-N-O-P-Q-R-S-T-U-V-W-X-Y-Z C CGS System Centimeter-Gram-Second system, the oldest system of units and the one used for presenting powder core data. Only the units for magnetizing force, magnetic flux density, length, mass and time are utilized. Statvolts and abamperes can be avoided by using the simple conversions and the magnetizing force equation provided in the Arnold Powder Cores catalog. Calibration (of a permanent magnet) The process of reducing the magnetic output of a saturated permanent magnet to a precise value. Usually achieved by applying a reverse magnetic field in stepped increments until the desired output is achieved. Also referred to as "tuning". Camber A measurement of edge curvature or "bowing" of a flat strip. Camber needs to be minimized in product used in stamping applications. Capacitor A device that stores electrical energy in a manner similar to the way an inductor stores magnetic energy. The unit of capacitance is the farad. Carbonyl Iron A relatively expensive iron powder used in low-permeability, high-frequency powdered iron cores. Case The enclosure surrounding a toroidal tape core, which protects it from being stressed by the environment of the application. Sometimes called a core "box." Standard materials are nylon, glass-nylon, and aluminum. Chemical Etch A process for making laminations from thin-gauge sheet. The lamination design is silk-screened onto the magnetic material, and light-sensitive chemicals are used to etch away the excess. This process is popular for low-volume laminations where tooling costs normally would be prohibitive. Choke An inductor. Closed Circuit Condition Exists when the external flux path of a permanent magnet is confined within high permeability material. Coercive Force, Hc The value of demagnetizing force that reduces residual induction to zero. The maximum coercive force, as measured on a saturated magnet, is proportional to the remanent flux density. See "flux density." It is expressed in oersteds or kiloAmps per meter (kA/m). Coercivity, Hci or iHc The resistance of a magnetic material to demagnetization. It is equal to the value of H where the intrinsic curve intersects the H axis in the second quadrant of the hysteresis loop. It is expressed in oersteds or kiloAmps per meter (kA/m). Coil Base Tube, or Coil Form For larger cores, where injection molded bobbins are not available, fabricated coil base tubes are used on which to wind the turns of wire. Coil Set A measurement of curl or set of a coiled strip; a measurement of the coiled configuration. Common Mode Filter An often-used type of EMI filter, which is wound with both conductors of the power source in such a way that noise not common to both conductors is filtered. The desired signal passes through the common mode filter unimpeded. Control Winding The winding on a mag amp or a saturable reactor used to control the amount of magnetic energy the core will absorb before saturating. Cooling Plate Usually Copper in design, a means to allow water to flow through the material in effect cooling down the surfaces in contact. Core Loss Power lost in a magnetic material when flux density changes. Also called iron losses or excitation losses. Crossbow A measurement of the deviation of a strip from a flat surface transverse to the rolling direction (across the width). Cruciform A core cross-section that has been "stepped" so it approximates a circle. This is desirable on high-voltage devices because it allows the use of circular cross-section coils without the loss of coupling that would be apparent if the core had a squared cross-section. The round coil is preferred because of corona. Current The rate of flow of electricity in a circuit. The practical unit is the ampere, which is one coulomb per second. Current Density The ratio of a current to the cross-sectional area of its path in a plane perpendicular to the direction of the current or the amps per unit of cross-section in the conductor. Curie Temperature, Tc Tc or Tc: The temperature above which ferromagnetic materials become paramagnetic, losing substantially all of their permanent magnetic properties. Some references state materials become non-magnetic above the Curie temperature. Cut Tape Cores Cores that are impregnated for mechanical rigidity. Please send all web related questions/comments to the Webmaster. TOP | BACK | HOME | HELP | MAP | CONTACT |
