LEM Engineers Invent Unique Magnetic Coupling Technology
March 2, 2010 by CouplingTips
Filed under Magnetic
LEM has introduced the first of its AC current sensor families based on Perfect Loop Technology. After calibration, the new RT series achieves absolute accuracy of better than 0,65% – including position error – making them the first split-core Rogowski coils to be suitable for use in Class 1 power devices.
An imperfect coil structure induces an unbalanced geometry and increases sensitivity to the position of the measured conductor within the sensor, or to the proximity of external electric cables. The RT series of sensors overcomes the problem of asymmetry resulting from the discontinuity at the sensor opening, which is inherent in conventional split-core Rogowski coils. LEM engineers have invented a unique magnetic coupling technology that allows a perfect extension of the magnetic flux at the loop opening, which compensates for coil asymmetry.
The thin, light and flexible format of the RT sensors allows them to fit into applications in which traditional current transformers are typically too heavy and bulky, especially when measuring high currents. Their split-core construction allows them to be easily wrapped around the conductor without dismantling cables or shutting down operation. The benchmark accuracy of RT series sensors provides enhanced performance in current and power monitors as well as energy meters.
Inch & Metric Magnetic Disk Couplings
June 24, 2009 by CouplingTips
Filed under Disk, Magnetic
New Hyde Park, NY – A new series of magnetic disk couplings from Sterling Instrument (ISO 9001:2000+AS9100B Registered Manufacturer) features no friction or wearing parts, uses no electricity and no magnetic particles to leak. These units, identified as the S50DCM… (inch) and S50DCMM… (metric) Series are stocked in 8 different bore sizes ranging from .1875″ to 1.000″ (5 mm to19 mm).The couplings consist of two opposing disk halves with powerful rare earth magnets. The torque applied to one disk is transferred through an air gap to the other disk. Because of its simple flat design, one can have angular misalignment of up to 3o or parallel misalignment of up to 1/4″ and still transmit nearly full rotational torque.
These 416 Stainless steel couplings incorporate an NdFeB, nickel plated magnet. The hub sections are offered singularly and are offered with or without a keyway and are fastened to shafts with an included set screw. The coupling O.D. ranges from 1.72″to 2.86″ (43.7 mm to 73 mm).
Other features include being incredibly accurate, repeatable torque control, and easy to adjust, easy to apply, smooth with no friction since there is no physical contact between driving and driven parts.
Sterling Instrument
www.sdp-si.com
