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November 2018: GMW will be at IEDM, December 1-5, San Francisco

GMW will be exhibiting at the IEEE International Electron Devices Meeting (IEDM) at the Hilton San Francisco, Union Square. The meeting runs December 1 to 5, with the Exhibition open on Monday 12pm to 4pm, Tuesday 8am to 4pm and Wednesday 8am to 12pm. In addition to Exhibition hours, Tom King will be attending the entire IEDM meeting.
We will be featuring GMW Projected Field Electromagnets with open access above the surface of the magnet for the sample under test, including:

  • 5207 Vertical Projected Field Electromagnet, which allows for greater vertical field where size and weight are less of a constraint. Fields to +/-1T at 4mm above the pole surface are obtainable using standard 1kW bipolar supply and standard poles. The 5207 allows for interchangeable custom pole geometries, and there for custom field profiles, for ease of transitioning from one experiment to the next with minimal down time.
  • 5203 Vertical Projected Field Electromagnet is widely used for MRAM test. Standard configurations allow for +/-0.5T with uniform vertical parallel field over a 5mm region of interest outside the body of the 5203 electromagnet. Mounting of the 5203 in a probe station can be above or below the wafer and custom pole geometries enable field optimization for different 5203 to wafer separations. The 5203 can be run with water to 63A, and for applications where water is undesirable, chilled, forced air can allow for operation to significant fraction of this.
  • 5204 Vector Projected Field Electromagnet, now in production, generates a field of up to +/-150mT in any direction at a location 4mm from the 5204 outside face. An axial hole through the Magnet enables optical alignment of the sample and associated probes.
    Applications include:
    • Nitrogen Vacancy (NV) center in diamond.
    • Biological sensitivity to magnetic field to simulate environmental fields or vector fields in organisms under microscope.
    • Spin Dynamics Studies
  • HTS-110 2T Projected Field Magnet with vertical projected fields to +/-2T in a compact, fast-ramping, cryogen-free superconducting electromagnet. 

In addition, we will also have information on C-Frame Dipole Magnets, including:

  • 3470HFAC for High Frequency AC Magnetic Fields. Using exotic materials for the core and Litz wire coils,  the 3470HFAC operates at frequencies from DC to 25kHz using commercial amplifiers. DC fields are to ±70mT. At 25kHz frequency, peak fields of 20mT are obtainable at an air gap of 35mm with direct drive and ±70mT at a comb of frequencies when resonantly coupled. For fields to +/-1T at modest frequencies (DC to ~100Hz), the 5403AC Electromagnet is stocked at GMW. 
  • 3480 Dipole Electromagnet is a higher power, higher field, version of the 3470 electromagnet that can generate over 3.5T at a 2mm Pole gap and over 2T in a 10mm Pole gap with a 1kW Bipolar Power Supply. The 3480 has the same physical footprint and external dimensions as the 3470 and weighs only a little more at 35kg. It is easily mounted on an optical table. For MOKE applications, a new Open Geometry version is available. This allows for both longitudinal and transverse MOKE in convenient geometry allowing greater access to sample.  An Extended Throat version allows for large diameter wafers to be inserted to gap, allowing for full coverage of 300mm wafer.

If you are in San Francisco for IEDM, please stop by.

October 2018: GMW is at Applied Superconductivity Conference in Seattle, October 29 to November 1

GMW is at Booth 28 of the exhibit at The Applied Superconductivity Conference (ASC) at the Washington State Convention Center in Seattle.
Philip Keller from Metrolab will be with Brian Richter showing the new MFC2046 Magnetic Field Camera system. The MFC2046 extends the PT2026 NMR Teslameter with a multi-probe array for rapid, high-resolution mapping of MRI or spectrometer magnets, while still supporting single-point probes with customizable field ranges, e.g. a single wide-band probe with range from <1.5T to >3.0T. Multi-point probe arrays for the MFC2046 for spherical or elliptical maps can include many fixed-frequency probes with an optional single wide-band probe integrated into the array to measure at ISO-Center to track the field as the magnet is ramped. Also shown from Metrolab are the FDI2056 precision digital integrator and 3-component USB Hall probes, available as instruments with USB interface and in IC form for high position resolution mapping of uniform or non-uniform fields.
Joey Aguas from Group3 Technologies is at ASC with the Group3 DTM-152 High Resolution (1uT in 3T), touch screen digital teslameter. Newly available from Group3 are also NIST-Traceable, Calibrated high field probes, with measurements to 9T.
Dr. Donald Pooke, CTO of HTS-110, will also be in Seattle  and prepared to discuss the CryoSaver Current Leads with nominal current ratings to 2kA. Donald can discuss the HTS-110 capability for specialized system design and manufacture of systems based on high temperature superconductors.
WeI will also have examples of:

  • Bartington Fluxgate Three Component Magnetic Field Probes (Bx, By, Bz) with analog outputs for low fields to +/-1mT. Single Component cryogenic versions are available for fields to +/-2mT and are being permanently installed in cryostats to monitor residual magnetic fields prior to cooling to avoid significant trapped fields in cryogenic cavities.
  • Senis Analog Hall Transducers with very small very small One-, Two- and Three-Component Integrated Circuit Sensors are applicable to high resolution field mapping and magnet control. Multichannel systems are available for multi-point monitoring of magnetic machines. Also from Senis, the NV1 Nanovoltmeter, suitable for flux change measurements, stretched wire or rotating coil magnet field measurements.
  • Danisense DC/AC Current Transducers with very high absolute accuracy and stability for magnet and machine test and control with current ranges from +/-50A to  +/-11kA full-scale.
  • GMW clamp-on current transducers with current ranges from 250A to 12kA full-scale. The CP series features frequency response from DC to 75kHz and +/-1% accuracy. With no magnetic core, the transducers can withstand high current overloads without damage, and recover immediately when primary current is within range.
  • High frequency current measurements can be made with the Magnelab CT (to 500MHz) and Bergoz FCT (to 1.7GHz) current transformers.
  • GMW Resistive Electromagnet Systems, including the Projected Field series for device characterization. The Projected Field Electromagnets are small enough to be located within a re-entrant tube to provide a controllable field within a vacuum chamber. Traditional C-Frame and H-Frame geometries are available with fields to 5T.

If you are attending ASC, please stop by.

September 2018: GMW is Exhibiting at SPE-ATCE, Dallas, TX, September 24-26, Booth 521

GMW will be exhibiting at the SPE-ATCE Conference in Dallas, TX from September 24-26.
The exhibition runs all day Monday and Tuesday, and 9am to 2pm on Wednesday the 26th. Brian Richter of GMW will be at Booth 521 and showing:

  • From Bartington Instruments, single and three axis fluxgate magnetometers featuring high temperature operation up to 215°C with low noise, small footprint and low profile applications in MWD Tools or Tools for pipeline inspection. For applications requiring fast measurements, the MAG639 features frequency response from DC to 12kHz. Packages for deep-sea operation to 5km depth are also available as part of the new MAG-13 line. The MS3 Magnetic Susceptibility system allows comparison of magnetic nanoparticle concentrations in liquid or slurry samples.
  • We will also have three-axis Helmholtz coils on display – the HC series allows for one, two or three axes, with orthogonality better than 0.1° and large homogenous volumes for calibration and test of fluxgate magnetometers prior to or post installation into tools. Reference magnetometers with accredited calibrations can be delivered with systems.
  • The TFM1186 Magnetic Field Probe with USB Digital output from Metrolab Instruments utilizes a Bartington MAG649 fluxgate magnetic field sensor. New models to ±2G full-scale have resolution to ±4nT, and orthogonality better than 0.5°. Three-component Hall-effect probes are available (with discounted pricing for multiple-probe purchases) with ranges from ±7.5mT to ±20T. Frequency for all probes is dc to 1kHz.
  • From Power Electronic Measurement (PEM) Rogowski Coil flexible, clip-around, AC Current Probes with full-scale primary currents of 30A to 1MA. The new MiniHF50 series extends the range of frequency response to 50MHz (-3dB), with models also available with low frequency response to <0.05Hz. Coils can be made to many meters in circumference for current measurement in large-scale installations. PEM Common Mode Current Probes with specially tailored frequency response are designed to measure the high frequency current from variable speed motor drives that can cause damage to bearings of large motors.
  • GMW DC/AC Clip-On and Clamp-On Current Probes for industrial current monitoring with better than ±1% accuracy to ±16kA and dc to >40kHz (-3dB) frequency response.

If you are attending ACTE, please stop by.

September 2018: GMW is Exhibiting at the IEEE Energy Conversion Congress, ECCE, Portland, OR, September 24-27 2018

The IEEE Energy Conversion Congress is at the Oregon Convention Center from Monday through Thursday, September 24 to 27. GMW is at Booth 403 in the associated Exhibit.
GMW will be showing Sensors, Probes and Instruments for the galvanically isolated measurement and control of electric current from uA to MA and dc to over 1GHz frequency response. We will be introducing new products:

  • AKM Semiconductor CZ370X pcb mounting Analog Current Sensors with peak current ranges of ±5A to ±180A, 5V Power Supply, +2.5V ±2V Linear Differential and Ratiometric Output Signal,  Response Time of 1us, dc to 400kHz (-3dB) Frequency Response, 1% accuracy, -40 to +105C Operating Temperature, 3kV Voltage Isolation, External Magnetic Field and dV/dt Rejection. These features are all available in a 12.7 x 10.9 x 2.25mm surface mount package for demanding switch mode applications like Variable Speed Motor Drives. 
  • DaniSense DM1200ID Fluxgate based, Closed-Loop (Zero-Flux) Current Transducer with ±1500 Peak Current, 1us Response Time, dc to 300kHz (-3dB) Frequency Response, ±7ppm Absolute Accuracy at DC, 45mm aperture. The DM1200 is appropriate for high accuracy current control of dc and ac current sources or sinks and high accuracy power analyzer measurements.
  • PEM CWTMini50HF Clip-Around, Flexible Rogowski Coil AC Analog Current Probe available in ±600A and ±1200A Peak Primary Current with ±6V signal output. This adds to the popular CWT Mini AC Current Probes to provide; Frequency Response to 50MHz(-3dB), 12.5ns Rise Time, up to 80kA/us Slew Rate, 100mm long Coil with 3.5mm Cross-section including an Electrostatic Screen for dV/dt rejection.

Ian Walker will be there with Ben Hartzell. If you are attending ECCE, Portland please stop by, we would like to take the opportunity to catch-up.

September 2018: GMW is Exhibiting at EV Tech And Battery Show, September 11-13, Novi, MI

GMW will be exhibiting at the co-located Battery Show and Electric & Hybrid Vehicle Technology Show in Novi, MI, September 11-13. GMW will be in Booth 426.
Conference details are available at: and
A free exhibition-only pass is available from either link above. 

GMW will be showing:

  • CPCO and CPC Clamp-on Current Probes featuring current ranges from ±250A to ±16000A and frequency response from dc to 75kHz (-3dB). The small size, light weight plus vibration and water resistance enables electrically isolated, long-term, sub-system current monitoring in test cells or vehicles, including long-duration, continuous testing at -30°C. 
  • Clip-around, Rogowksi Coils AC Current Probes from Power Electronic Measurement (PEM), with Coil cross-section down to 1.6mm and Coil lengths to many meters with full-scale current ranges from 30A to 1MA. Newly available are probes with response to 50MHz (-3dB), making these Probes applicable to a wide range of isolated current measurement on switching device leads, on leads from VSD to motors and in resonant wireless charging coils. Also available from PEM are the CMC Common Mode Current Probes with a frequency response tailored to reject the nominal drive current frequencies but have high sensitivity in the high frequency common mode current region.
  • IPCT Zero-Flux DC Current Transducers from Bergoz Instrumentation have ranges from 10mA to 5A full-scale. The IPCT features a large 82mm (3.2”) aperture, dc to 4kHz frequency response and current resolution to 10uArms and can be used for dc or ac, differential or leakage current measurements on complete cables for ac-dc chargers, PV to dc battery storage, variable speed drive to motor assemblies. The very high stability and reproducibility of these Transducers enable applications to product development, production quality control or long-term condition monitoring. 
  • DC/AC Current Transducers from Danisense, with very high resolution and accuracy, wide dynamic range with full-scale current ranges to 10kA and dc to 500kHz(-3dB) for charge-discharge measurements of batteries or motor drive efficiency measurements using power analyzers or high-resolution data loggers.

Our partners from AKM Semiconductor will be showing Low Noise, Coreless Hall-effect Current Sensor ICs, with the new CZ-37xx series featuring ranges from ±5A to ±180A and typical accuracy of ±0.5% (Ta 0 ~ 90°C) .Chris Baltar and Yuko Nishikawa from AKM will be exhibiting at the Asahi Kasei booth 2319.

For current instrument calibration, GMW is now ISO-17025 accredited from 40A to 8kA at both DC and 60Hz. Sandro Renteria, Calibration Manager at GMW, will be with Brian Richter at the GMW Booth. If you are attending, please stop by.

August 2018: GMW is at AMEREM 2018, Santa Barbara, August 27-31

GMW will be exhibiting at Amerem 2018 in Santa Barbara. The exhibition runs from Tuesday August 28th through Friday the 31st – GMW will be in Booth #4. 

Richard Leonard from Pulsed Power & Measurement (PPM) will be with Brian Richter. We will be showing:

  • Sentinel3 Multichannel Analog Signal Fiber Optic Link with adjustable input signal gain, temperature compensation and frequency response up to 3GHz enables accurate time domain and frequency domain measurements. A long-life Battery that can be recharged from the main chassis allows for long-life testing of High Power Electromagnetics.  Single and 8-channel Shielded Transmitters and multichannel Receivers provide for up to 288 channels to be monitored from a single chassis. Applications include low level swept current and frequency for aircraft and MIL-STD-188-125 testing.
  • point2point (p2p) Single Analog Signal Channel Fiber Optic Links come in AC or DC-coupled versions, with bandwidth from DC-40MHz and to 3GHz for AC coupled links. Compact, EMP-Shielded enclosures allow for high e-field gradient applications. Remote control of Battery power On/Off is possible, allowing for single shot measurements to be set up well in advance. p2p links have been used extensively for MIL-STD-461-RS105.
From Bartington Instruments, we will show: And from PEM:
  • Rogowski Coil AC Current Probes for pulsed current measurement to over 1MA for applications in lightning testing and power system transients. A new version of the CWTMini50HF with frequency response to 50MHz (~12.5ns risetime) is now available.

If you are in Santa Barbara for AMEREM, please stop by.

July 2018: Three Component Magnetic Field Measurement Probes with USB Digital output available from GMW

GMW offer a unique range of Magnetic Field Measurement Probes with USB digital output for direct connection to the USB port of PDA, Tablet or Laptop devices for the measurement or mapping of the Bx, By, Bz components and calculation of the total field, B. All digitization and correction is within the Probe. Power is derived from the USB Host.

For low fields to +/-100uT (+/-1G) and dc to 1kHz (-3dB) frequency response, the Metrolab 1186 utilizes a Bartington Fluxgate Sensor to provide 4nT field resolution with better than 0.5 degree angular alignment. The 1186 is appropriate for site surveys of magnetically sensitive equipment and for checking field amplitude and angle of test equipment for magnetic compasses and sensors.

For measuring magnetic fringe fields from magnets, motors, transformers and inductors the Metrolab 1176LF has a +/-8mT (80G) field range, 2uT (20mG) resolution and better than 0.2 degree angular alignment with dc to 1kHz frequency response.

For very high accuracy magnet qualification or magnet field mapping, the Metrolab 1176MF has selectable field ranges of +/-0.1T (+/-1kG), +/-0.5T, +/-1T and +/-3T with a field resolution of 0.1mT. The active volume of the integrated Three Component Field Sensor is 0.15x0.15x0.01mm enabling very high position and angle resolution. The Metrolab 1176HF is similar but with +/-0.1T, +/-0.5T, +/-3T and +/-20T ranges.

The Senis 3MTS Probe has selectable field ranges of +/-0.1T (+/-1kG), +/-0.5T, +/-3T and +/-20T with 12-bit resolution and dc to 500Hz frequency response. The field sensor active volume is 0.15x0.15x0.01mm located 0.5mm from the tip of the very small, 0.9mm thick by 4mm wide, Probe enabling high position and angle resolution field measurement very near a surface or in a thin slot. Two versions are available: the 3MTS-1 is a Hand-held, 100mm long, carbon-fiber Probe for field surveys; the 3MTS-2 has a 0.9mm thick, 4mm wide, 8mm long field Sensor with a Cable length of 1, 2 or 5m and is suitable for field mapping or magnet control.

July 2018: End of Fiscal Year Inventory

About this time of year, GMW starts to get enquiries from customers about products being delivered and invoiced before the end of the September 30 fiscal year. GMW products in stock are listed on the appropriate product price page by highlighting in yellow. GMW generally are stocking:

  • Low-Noise and Compact Fluxgate Magnetometers from Bartington Instruments for high resolution magnetic field measurements to +/-2mT.
  • Hall Effect measurement probes from Metrolab, Group3 and Senis with one and three component probes to +/-20T.
  • Clamp-on and Clip-on DC Current Probes (GMW) and High Accuracy Fluxgate DC Current Transducers (Danisense, Bergoz) for current measurement from +/-1mA to +/-10kA.
  • Rogowski Coil AC Current Probes from PEM for clip-around current measurements up to 30MHz.

Most products not stocked can be delivered within about 6-8 weeks.

June 2018: New Product Announcement

New from Bergoz Instrumentation is the CWCT and BCM-CW for measurement of the average current of CW or macropulse beams up to 500MHz RF with resolution <1uA and dc to 100kHz output bandwidth independent of bunch shape/width. The CWCT is ideally suited to sub-relativistic proton/ion beams, to measure loss along the accelerating path.

Read More..

May 2018: Building Your Magnetic Field Mapper with LEGO® by Philip Keller of Metrolab

May 2018: GMW will be at the IPMHVC Conference, Jackson Hole, WY June 3-7

GMW is exhibiting at the International Power Modulator & High Voltage Conference in Jackson Hole, WY from June 3rd through 7th. For details please see:
GMW is at Booth 21, and we will be showing examples of the PPM Fiber Optic Links for analog signals:

  • The Sentinel 3 Intelligent Fiber Optic Link system, now in full production with over 100 channels deployed world-wide. With bandwidth to 3GHz, Senitnel 3 improves upon existing Fiber Optic Links systems with faster set-up times, reduced measurement times, greater testing endurance and increased confidence in test data. Up to six Receiver modules with one, two or six inputs can be mounted in a single 19” chassis, each module with a different programmable configuration as needed. Each Receiver module can be connected to a single channel or eight channel Transmit head, thereby allowing up to 288 channels within a single rack. 
  • The p2p fixed gain Fiber Optic Link system for high voltage isolation, transmission over long distances and/or very high EMP shielding effectiveness. The p2p system offers DC links with frequency response to 40MHz and AC links with frequencies from 40Hz to 3GHz.

Phil Surman of PPM will be with Brian Richter at the GMW booth and would be pleased to review recent development efforts at PPM.
GMW will also show measurement sensors and transducers for electrically isolated current measurements including:

  • PEM Clip-On AC Rogowski Current Probes with frequency response to 30MHz, current ranges to over +/-300kA and Coil lengths to over 30m. Applications range from ac power measurements, through power semiconductor switching waveform characterization to lightning current discharge monitoring. The MiniHF versions include electrostatic shielding of the Rogowski Coil to reduce capacitive coupling from very high dV/dt on the primary conductor and extend the frequency response to 30MHz.
  • Passive AC Current Transformers from Bergoz and Magnelab with frequency response extending to 1.5GHz and with sensitivities as high as 5.0V/A. The Bergoz FCT complies with MIL-STD-188/125, standards for high-altitude electromagnetic pulse (HEMP) hardening of fixed and transportable ground-based facilities which perform critical, time-urgent command, control, communications, computer, and intelligence (C41) functions.
  • CQ-330x series board mount Current Sensors from AKM Semiconductor feature frequency response from DC to 1MHz, full-scale currents from 4.5A to 35A with 3kV of isolation.
  • DaniSense Fluxgate DC Current Transducers  have very high accuracy and resolution for current measurement and control covering currents from 50A to 10kA and frequency response from dc to 1MHz;
  • VAC 464x series Closed-loop Current Transducers with 0.5% accuracy and currents to 2,500A and frequency from DC to 100kHz.
  • GMW CPCO and CPC Clip-on Current Transducers featuring DC-75kHz response and current ranges from 250A to 16kA. Diameters from 27mm to 160mm are available in a variety of output signal options.

Examples of Magnetic Field measuring instruments  will include Bartington Fluxgate sensors for low fields to 2mT (20G), Senis One- and Three-Component Analog Hall Transducers available with frequency response from DC to 75kHz.

April 2018: GMW is Exhibiting at International Particle Accelerator Conference (IPAC), Vancouver, April 29th - May 2nd

GMW will be exhibiting at IPAC18 in Vancouver, Canada. The conference opens with a reception Sunday Evening April 29th in the Exhibit Hall. The exhibition remains open all day Monday through Wednesday.  GMW is in booth 703. Metrolab Technology will have the booth adjacent, number 701. For details see:

GMW will be showing:

  • From Bergoz Instrumentation, accelerator beam diagnostics for beam current, position and profile. Featured is the new CWCT and BCM-CW for measurement of the average current of CW or macropulse beams up to 500MHz RF with resolution <1uA and dc to 100kHz output bandwidth independent of bunch shape/width. The CWCT is ideally suited to sub-relativistic proton/ion beams, to measure loss along the accelerating path.
  • From Bartington Instruments, Cryogenic Fluxgates for magnetic field monitoring in cryocavities, as well as  3-axis room temperature Fluxgates for environmental field measurements with mG resolution and response from DC to 12kHz.
  • From Danisense, very high accuracy, ultra-stable, DC Current Transducers from 20A to 12kA with optional built in full-scale calibration windings and options for current or voltage output.
  • From GMW, clamp-on current probes for currents from 250A to 16kA. Frequency from DC up to 75kHz and accuracy of +/-1% are suitable for redundant dc or ac current monitoring or troubleshooting of magnet power supply outputs.
  • From Group3, sub-mG resolution digital magnetic field probes for DC fields with electrical and fiber optic outputs. Calibrated probes to 9T are available.
  • From HTS-110, High Temperature Current leads for superconducting magnet applications.
  • From PPM, DC-40MHz DC-coupled and 40Hz to 3GHz AC coupled fiber optic links for signal transmission and EM immunity and/or isolation.
  • From Senis, single and three-axis analog Hall probes in a wide range of geometries. Also from Senis, the NV1 Nanovoltmeter, suitable for stretched wire and rotating coil output measurements, particularly for fringe field end-effects.

Tom Delaviere from Bergoz Instrumentation will be with Brian Richter from GMW. Philip Keller from Metrolab will be showing their range of NMR and Hall Measurement Instrumentation as well as Precision Digital Integrators in the adjacent booth. Both new NMR and Hall arrays for precision mapping will be shown.
If you are in Vancouver, we hope to see you at IPAC18.

GMW will be at Booth 827 at the American Physical Society (APS) March Meeting. For details, please see:
The Exhibition Hall is open Monday Evening March 5th at 6:45pm for a Welcome Reception and all day Tuesday to Thursday. GMW will feature:
GMW Resistive Electromagnet Systems for spintronics, biological studies, thin films, magnetic materials, and magnetic devices.

  • Model 5405 Electromagnet, has the same dimensions and weight of the Model 5403. This C-Frame electromagnet can reach 2T at 2cm gap with 6kW-rated coils.
  • The BPS-85-70 [pdf brochure] from IECO is 6kW true bipolar power supply, with parallel operation possible for up to +/-140A excitation. When matched with the Model 5405, B-H loops of +/-2.6T over 1cm gap are possible at ~1Hz operation.
  • GMW projected field electromagnets, available as optimized for parallel or perpendicular field. The new model 5207 [pdf brochure] provides fields of over 1T vertical field at 5mm above pole face with single 1kW bipolar supply. The Model 5204 is true vector magnet, with ability to generate fields in any direction above top surface of the magnet at frequencies to 200Hz.
  • Model 3480 Electromagnet, has the same dimensions and weight as the well-known GMW Model 3470 table-top electromagnet. Through higher current density coils and shaped poles, the 3480 can reach fields of over 2T at a 1cm gap. Customized poles for EPR, MOKE and customer-specified geometries are possible.  GMW will have the Model 3480-OG, designed to allow for 60 degree incident angles over 1cm gap, on the booth for display.
  • Model 3470HFAC dipole electromagnet generating ±70mT peak fields from dc to 25kHz in an air gap of 35mm.

Bartington HCx-3, three-axis Helmholtz Coils with fields to +/-1mT on each axis and frequencies to 5kHz. The MAG-13 series reference magnetometers and field cancellation software allow for applications requiring cancelling of background fields, including at AC Mains power frequencies.
HTS-110, manufacturers of High Tc Superconducting Magnet systems, will be in booth 106. Dr. Taotao Huang, Magnet Design Engineer at HTS-110, will on the HTS-110 stand.
Magnetic Field Measurement Instrumentation

  • Senis Hall effect Magnetic Field Transducers, Instruments and Mapping Systems with one- and three-component Integrated Field Sensors available in field ranges to 20T and frequency response from dc to 75kHz. These are particularly appropriate for very high position resolution field mapping of magnets and magnet arrays. Very small probe package geometries are available. We will have on the stand the new 3MTS digital Hall probe from Senis. The 3MTS is an ultra-compact (less than 1mm thick), three-axis probe with USB output and +/-1% accuracy, all while fitting comfortably in the palm of one’s hand.

Mr. Brian Richter, GMW President, Dr. Tom King, Lead Magnet Scientist, and Mr. Lalo Guitron, GMW Sr. VP of Operations, will be available for detailed technical discussions and applications support. If you are in Los Angeles, please stop by.

January 2018: Senis, Newsletter January 2018

October 2017: New developments in GMW dipole electromagnets

GMW is continuing to update its electromagnet product offering and is pleased to announce the new 5405. This magnet is a direct fit, form and function upgrade for the earlier 5403 system with identical poles, mounting holes and weight. The 5405 offers significant increase in field strength above the 5403; across a gap of 20mm the 5405 generates continuous 2T with the 5403 generating 1.6T.

The 5405 provides a peak continuous field of 4.3 Tesla across a gap of 2mm. The 5405 has been optimized to operate in conjunction with an +/-85V, +/-70A true Bipolar power supply. When coupled with this supply the 5405 will operate up to 70A. When operated with a unipolar power supply the 5405 can operate up to 100A for short periods.

The 5405 is designed with many options and configurations. A standard range of brackets allow the magnet to be oriented to provide magnetic field horizontally, vertically, at 45° or any orientation as a custom option. The design also allows for the yoke to be split allowing for elongation of the magnet at 25mm intervals, it is very simple to modify the magnet to fit around any working environment. The magnet is protected by a temperature interlock that removes power in the event of over-temperature. A further safety option includes a water flow switch that can be included in the interlock circuit. Yellow alert status can also be included by an additional water flow meter to indicate when maintenance is required. Similarly, a temperature based yellow alert can be added to show that the magnet is operating warmer than usual but within acceptable range; indicating maintenance is required.

Preliminary Specifciations: 5405 Brochure, October 2017

September 2017: High-Temperature Fluxgate Magnetic Field Sensors and Metrology-grade Helmholtz Coils from Bartington Instruments

GMW Associates and Bartington Instruments would like to update you on the latest product development in area of magnetic field generation, measurement and control for fields to 20G and frequencies from DC to 12kHz.

For more information please click here

August 2017: GMW is Exhibiting at the Electric & Hybrid Vehicle Technology Conference, Novi, MI, Sept 12-14, 2017; Booth 826

GMW will be showing Sensors and Instruments for magnetic and electrical measurements used in motor and battery development and test.

For more information please click here

August 2017: GMW & Bergoz Instrumentation at IBIC, Grand Rapids, MI Aug 20-24

GMW will again be exhibiting at the upcoming International Beam Instrumentation Conference (IBIC), hosted by FRIB and held in Grand Rapids, MI at the Amway Grand Hotel and Conference Center.  The Conference opens with a Sunday evening reception, with exhibition stands open from Monday through Wednesday afternoon.

For more infrormation please click here

August 2017: Compact HTS Magnets for Neutron Scattering Sample Environments

Since establishment in 2004, HTS-110 successfully designed and manufactured many challenging magnet systems around the world, using HTS technology.

For more infrormation please click here

August 2017: GMW is exhibiting at The 2017 Symposium on Electromagnetic Compatibility, Signal and Power Integrity, Washington, DC. August 7-11

For more infrormation please click here

June 2017: Fermilab 50th Anniversary Symposium & June 8th Annual Users Meeting

GMW will be participating in Fermilab’s 50th Anniversary Symposium and Users Meeting next week. The Symposium is June 7th and Users Meeting is June 8th. For details, see:

Read more >

May 2017: High Speed, High Resolution Magnetic Field Mapping System

The SENIS Magnetic Field Mapper can map dc and ac magnetic fields associated with permanent magnets and electromagnets.

Read more >

May 2017: Senis, Newsletter May 2017

SENIS AG provides magnetometers, mappers, current sensors and corresponding services .

Read more >

April 2017: GMW is exhibiting at ISMRM, Honolulu, April 22-27, Booth 411

Eddy Current Detection of Mechanical Faults in Permanent Magnets and in Magnet Blanks Prior to Magnetization

March 2017: AKM, VAC, DaniSense, PEM and GMW Current Sensors and Probes at APEC, Tampa, FL

March 2017: Working at low temperatures?

March 2017: GMW is Exhibiting at APS March Meeting, New Orleans, LA, March 13-17

GMW CPC Clip-On DC/AC Current Probes with Current ranges to +/-2000A

February 2017: GMW 3480 Electromagnet Systems for FMR Spectroscopy and EPR Measurements

January 2017: Presentations Magnetics 2017

November 2016:History of PEM Rogowski Coil AC Current Probes

October 2016: GMW introduces 3480 bench-top lab magnet
3480 vs. 3470 Comparison

August 2016: Metrolab launches the PT-2026 NMR Teslameter (Gaussmeters)

June 2016: GMW Extends AC Electromagnet Capabilities with 3470HFAC High Frequency AC Magnet

GMW magnets are designed for DC operation and AC operation up to a few Hz and have been operated up to tens of Hz. GMW is now offering the higher frequency 3470HFAC system which operates up to 30 kHz. This new system is configured as a C-frame dipole and delivers field up to 70mT across a 35mm pole gap. The system has been used for neutron studies, and is also suited for Fine Particle studies . Full specifications can be found on the 3470HFAC Preliminary Datasheet (pdf).

GMW has also extended its line of projected field magnets, offering the original 5201 in-plane magnet, the 5203 projected vertical (perpendicular) field, 5205 vertical (perpendicular) field large area, low profile magnet, and 5204 (pdf) projected 3-axis vector magnet to be completed late 2016. This complementary family of magnets serves many areas of spin dynamics whether the architecture is based on in-plane or out-of-plane spin, or if an AC or rotating field is required. Peak fields range from ±300mT for 5204 to ±0.8T for 5203. All 520x models allow for customized poles or pole tips to optimize peak field vs. uniform field area or for field shaping. 5204 is being offered as a central tool for FMR studies as it can provide both the DC bias field and the AC sweep with both the DC and AC components oriented in any direction. For higher projected fields to >2T, GMW offers a Projected Field High Temperature Superconducting magnet (pdf) from HTS-110.

Additional magnets from HTS-110 include low-profile (height < 35mm) solenoids to ±3T, high-field large bore (54mm) solenoids to ±14T, and fast-ramp (360s + 40s dwell over 4 quadrants) dipole magnets to ±8T.

May 2016: GMW is at SpaceTech/Aerospace Engineering, May 24-26 in Pasadena, CA

GMW is in booth 1012 at the combined Space Tech and Aerospace Electrical Systems Expo. For more information, see: and
Note that complimentary registration for free sessions and Expo is available from either link.

The Expo moves this year to The Pasadena Convention Center in downtown Pasadena, opening on Tuesday the 24th at Noon and running through Thursday afternoon. GMW will be showing instrumentation for measurement and mapping of magnetic fields and calibration of magnetic sensors.

GMW will have details on the new PPM Sentinel 3 Fiber-Optic Link system specifically designed for aircraft test. With touch screen monitoring and capability to link up to 288 channels into single 19” rack-mounting chassis, the Sentinel 3 is ideal for NEMP testing (MIL-STD 188-125) as well as Low Level Swept Field and Low Level Swept Current tests. Transmit heads are electrically shielded to 100kV/m, well-suited for Full Threat Environments.

GMW will also be showing instrumentation for the measurement of current in electric power conversion systems.

If you are at Space Tech or Aerospace Electrical Systems please stop by.

Thank you,
Brian Richter

GMW Associates

March 2016: Bartington Newsletter

Bartingon Instruments is launching two new OEM products: the Mag646 single axis sensor and the Mag651 low power three-axis sensor.

Download the Newsletter

January 2016: New Magnets from GMW: High Frequency and High Field

January 2016: New High Temperature and Low Noise Bartington Three-Axis Fluxgate Magnetic Field Sensors from GMW

December 2015: Systems for Visualizing and Mapping Magnetic Fields in Space and Time

December 2015: GMW Extends Project Field Electromagnet Capabilities

November 2015: Article: The Future of NMR Magnetometry.

August 2015: Magneto-Optic Films From Matesy
New Product Line: Magneto-Optic Films From Matesy. Matesy magneto-optic films allow real time visualization of magnetic fields.

For more information, click here

December 2014: Bartington Newsletter

New magnetic field probe for customer-designed elctonics. 1 metre Helmholtz Coil now available and real world application updates.

Download the Newsletter

October 2014: Senis Field Mapper Video

The High-end All-in-One Magnetic Field Scanning System SENIS MMS-1A-RS enables a user to quickly map the magnetic field around an permanent magnet or electromagnet with highest resolution and accuracy.

Watch Video Directly.

September 2014: Senis Newsletter

Overview of ManaChip Semiconductor and Senis sign patent Licence agreement. Senis at IEEE 29th International Conference on Microelectronics(MIEL 2014) and other conferences

Download the Newsletter

July 2014: Senis Magnetic Field Measurement Catalog

New products: Probes as thin as 0.25mm, Next-Generation Magnetic Field Mapper, Defectoscope for crack detection.

Download the newsletter >

June 2014: Bartington Newsletter

Mag566 launched in satellite for attitude sensing and VLF wave measurement; New high temperature probes up to 175°C; Compact Sensors for Security Applications.

Download the newsletter >

May 2014: Powerguru Article
Next Generation Current Probes for High Speed Power Density Appliations.

Read Article

March 2014: Bartington Newsletter
1-metre Helmholtz Coil under development and Price Changes.

Download the newsletter > 

April 2014: Senis Newsletter

Senis conference schedule update.
Download the Newsletter >

Mar 2014: GMW features current measurement instruments and sensors at APEC, Fort Worth, TX

The Applied Power Electronics Conference, APEC, is in Fort Worth, Texas, March 16-20, 2014. For details please see:
Note that Exhibit Only Registration is available at No Charge. Please see:

GMW is at Booth 606 and will present Instruments and Sensors for the voltage isolated measurement of electric current:

  • From DaniSense: DC/AC Current Transducers with full-scale current ranges of 300A, 900A and 3000A and primary/signal current ratios of 500:1 to 1500:1. New zero-flux, closed-loop design gives improved amplitude and phase accuracy for demanding applications like current range extension for power analyzers or current feedback in low noise, high precision power supplies and amplifiers. Each Transducer is provided with the Factory Calibration measurement of amplitude and phase response versus frequency to 300kHz. Options include current or voltage signal output, and calibration winding. Henrik Elbaek, CEO of DaniSense, will be at the GMW Booth.
  • From Power Electronic Measurements (PEM): Rogowski AC Current Probes with matching Integrator in a wide range of Coil cross-sections and lengths. Very thin Coils are appropriate for isolated current measurements to 6kA peak and 30MHz on the leads of power devices. Larger Coils are available in current ranges to 1MA and Coil lengths to many meters to provide signal inputs to waveform and power analyzers. Options are available for three phase measurement, instantaneous or rms output, voltage or 4 – 20mA signal. Modified versions are available for specialized applications such as 13.56 MHz industrial rf current monitoring. Dr Chris Hewson, President of PEM, and Joanne Aberdeen, Director of Engineering, will be supporting the PEM products.
  • From Magnelab: Passive Current Transformers (CT) with high sensitivity to 5V/A and high frequency to 500MHz for demanding pulse and cw rf current measurements.
  • From GMW: Slip-On and Clamp-On Current Probes to provide convenient, reliable DC/AC high current monitoring to 16kA in high magnetic field environments such as electrochemical and electrowinning applications. Analog and wireless output options.  
  • From Senis: High sensitivity pcb mounting Current Sensors with full-scale ranges from 0.25A to 10A for current present monitoring or use with sensing resistors for isolated high voltage measurement. Compact Multichannel Current Monitors with DIN Rail or panel mounting with full scale ranges to 50A for condition monitoring of electric heaters, lamps and motors. We will have Nebojsa Radosevic from Senis at the GMW Booth.
  • From AKM: Miniature pcb mounting current sensors to 80A fs with very low noise and dc to over 400kHz frequency response for linear and high frequency pwm power converters and motor drives. Low noise Linear Hall IC for current and position sensing.

Lou Law and Eric Mueller will  also be with me at the GMW Booth. If you are attending APEC, please stop by. Thank you.
Best wishes,

Ian J. Walker
VP Engineering,
GMW Associates

Nov 2013: Senis Newsletter

Ceramic hall probes as thin as 0.5mm; High Frequency Hall Probes up to 0.5MHz.
Download the Newsletter >

Nov 2013: Metrolab: Measuring Magnetic Field Transients

High resolution, fast digital integrator (FDI) for measuring magnetic flux. Published in Magnetics Technology International. Author: Phillip Keller, Metrolab Technology SA
Full Magazine, Magnetics Technology International, 2013 Annual>
Measuring Magnetic Field Transients (article only, PDF)>

Prior Metrolab Articles in Magnetics Technology International
Recent Advances in Hall Magnetometers, 2012 Annual (article only, PDF)>
NMR Magnetometers, 2011 Annual (article only, PDF)>

Oct 2013: Bartington Newsletter

Mag-13 Fluxgate Magnetometers; Helmholtz Coil System; Gradiometry site survey locates Roman villa.
Download the Newsletter >

June 2013: Danfysik Newsletter

Danfysik Green Magnet Accelerator Magnets; MW Range Power Supplies for ISIS and INFH.
Download the Newsletter >

May 2013: Senis Newsletter

Digital Teslameter (Gaussmeter) with 1ppm resolution and 0.001% accuracy; SENIS at Sensor + Test in Nurnberg, Germany and CWIEME in Berlin, Germany.
Download the Newsletter >

February 2013: Bartington Newsletter

Bartington Collaboration with Metrolab Teslameters (Gaussmeters); New Digital 3-axis Gradiometer; New Degaussing Wand and Magnetic Shields; Magnetic Susceptibility in Banknote Security
Download the Newsletter >

October 2012: Metrolab Developments in Hand-Held Magnetic Field Measurement

Recent developments expand range of hand-held 3-axis magnetic field measurement from nanotesla to 14 Tesla. Published in Magnetics Magazine. Author: Phillip Keller, Metrolab Technology SA.
Read Full Article >

September 2012: Bartington Newsletter

New 3-Axis Helmholtz Coil System; Down-Hole Magnetic Susceptibility Measurement; Autonomous Underwater Navigation via Magnetic Anamolies. Download the Newsletter >

May 2012: Bartington Newsletter

New Low-Noise Magnetometer (Mag628), Earthquake Prediction, Magnetic Susceptibility in Forensics. Download the Newsletter >

January 2012: Bartington Newsletter

New Fluxgate Magnetometer products (Spacemag, Mag634), MS2/MS3 for QC and more. Download the Newsletter >

November, 2011: GMW ISO 9001:2008 Certification

GMW Associates is proud to announce achievement of ISO 9001:2008 Certification. Certification was conducted by Perry Johnson Registrars, whose accreditations include UNAB (ANSI-ASQ National Accreditation Board) and UKAS (United Kingdom Accreditation Service).

ISO 9001:2008 Certification is an internationally recognized set of standards for quality assurance, quality management and continuous improvement. The standards represent best practices, policies and procedures to ensure that GMW will continue to consistently meet our customers' needs for superior products and technical support.

. Download the Certificate >

September, 2011: Bartington Newsletter
New Fluxgate Magnetometer prodcuts, updates to Bartsoft for MS2/MS3 Magnetic Susceptibility Meter and more. Download the Newsletter >

April, 2011: AKM Magnetic Sensors 2011 Product Guide
New product guide. AKM (Formerly Asahi) has a new guide to their magnetic sensors product range, covering Hall Elements, Hall Switch ICs, Hall Two Axis IC, Hall Arrays and Semiconductor Magneto Resistive Sensors. Download the Guide >

December, 2010: LEM Current and Voltage Transducers
As well as the LEM IT series of Current Transducers and Instruments, originally developed by Danfysik ACP Division, GMW is now stocking selected LEM Hall Current Transducers for test and measurement applications. These are appropriate for production testing of electrical appliances, motors and vehicles where the very high accuracy of the IT series is not necessary but ohmic isolation and high reliability are crucial. With the addition of LEM Voltage Transducers covering 500V to 6000V and frequencies from DC to over 100kHz for lower voltage units, GMW can now offer the capabilityto convert high level current and voltage to isolated low level signals for product performance and/or power test and measurement.

June, 2010: Asahi Magnetic Sensors
Asahi have a new summary of their magnetic sensor product range covering Hall elements, Hall Switch IC, Hall Linear IC, Hall Two Axis IC, Hall Arrays and Semiconductor Magneto Resistive Sensors. Applications include non-contact sensing of proximity, linear position, angle position, rotation, and electric current. Please contact GMW for applications engineering support. Download the Brochure >

October, 2009: Asahi EM-3242 Magnetic Angle Sensor
The Asahi EM-3242 is a very small, 6 pin, SOIC IC which enables non-contact, low wear, full 360°, angle sensing utilizing a simple two pole magnet. Operation is from a nominal 3V source with a ratio metric, analog output of 0.3V to 2.7V. Power draw is 8mA in wake mode and 1µA in sleep mode. Contact GMW for Engineering Kits and support to apply the EM-3242 to remote readout of valve, arm, vane and meter position; gas and fluid metering; non-contact operator controls; or servo position control. More >

May 18, 2007: GMW introduces new magnetic field sensors products at Sensors Expo
At Sensors Expo, June 11-13, 2007 Rosemont, IL, Booth 406, GMW will be showing magnetic field sensors that are particularly suited for non-contact measurement of:

Machine Condition: The Ametes MFS-3A is a high-sensitivity, three-axis, Magnetic Field Sensor with linear analog outputs for Bx, By, and Bz. With a bandwidth if dc to 100kHz, the MFS-3A can be located outside electric motors, generators, transformers, or actuators to monitor the external magnetic field magnitude and or frequency components. These parameters will change with electrical or mechanical loading to give an isolated, non-contact indication of the “machine condition” in a manner analogous to vibration monitoring of rotating machinery.

Electric Current: The Sentron CSA-1V is a high-sensitivity, high-stability, linear Hall-effect IC with magnetic field sensitivity in the plane of the device and frequency response dc to 100kHz. These features enable the CSA-1V to be used as a compact, low cost current sensor, particularly for circuit protection applications. It can be mounted directly over a current trace on a PCB or on the surface of a high current bus bar. GMW offer Engineering Kits to cover full-scale current range from 250mA to 4000A Ametes CS Current Sensors are available with high-sensitivities of 10V/A, 1V/A, and 0.25V/A. High voltage isolation of 5kV is achieved by mounting the CSA-1V to measure the magnetic field inside a small coil carrying the primary current.

Rotation Angle: With no programming and no calibration requirement the Asahi Kasei EM3241 provides a linear, analog output directly related to the angle of the magnetic field in the plane of the device. High magnetic sensitivity field sensitivity enables the use of small, low-cost permanent magnets for angle sensor or rotation sensing with better than 0.7° angle resolution over a full 360° at rotation speeds well in excess of 200Hz (12000rpm). Very small size (3.6 x 3.0 x 0.95mm) and a low-power sleep mode (<1µA) suggest the EM2341 will enable new portable and wireless applications.

April 28, 2006: Spallation Neutron Source, located at Oak Ridge National Laboratory, generated its first neutrons.
One of the largest and most anticipated U.S. science construction projects of the past several decades has passed its most significant performance test. The Department of Energy's Spallation Neutron Source, located at Oak Ridge National Laboratory, generated its first neutrons on April 28, 2006. GMW has supplied SNS with instrumentation including: Group3 Control system and Bergoz Fast Current Transformers for use in the Front-End Systems; Bergoz Fast Current Transformers and Low Level RF analog front end for use in the Linac; Danfysik Magnet Power Supplies for use in the Accumulator Ring; and Danfysik Power Supplies, Danfysik Current Transducers, and Group3 Digital Teslameters (Gaussmeters) for magnet system test.

June 6, 2005: GMW introduced new Angle Sensor products at the Sensors Expo in Chicago
GMW introduced new Angle Sensor products at the Sensors Expo in Chicago, June 6-8, 2005. When paired with the Sentron 2SA-10 Angle Sensor IC the GMW360A Sin/Cos to Analog Interpolator IC provides linear 0.4V to 4.5V and PWM signals proportional to angle over the 0 to 360degree range. An electrical "Zero Angle" can be set at any mechanical position after system assembly.

May 27, 2005: The AN_360KIT Application Engineering Kit is available for test and evaluation
The AN_360KIT Application Engineering Kit is available for test and evaluation. A combination of the 2SA-10 and GMW360A is offered as the GMW360ASM Angle Sensor Module. This is a cylindrical package of 0.5inch diameter by 0.2inch height (12.70 x 5.08mm). A single 5V supply is required with no other external components.

March 21, 2004: GMW introduces the Model 5751 HTS Short Solenoid
As an extension to it's Laboratory Electromagnet product line GMW introduced the Model 5751 HTS Short Solenoid at the APS (American Physical Society) Meeting in Los Angeles, California. With a 35mm diameter by 72mm long, room temperature bore the 5751 generates controllable magnetic fields between ±1Tesla (+/-10,000Gauss). This is 5 to 10 times the field readily generated by a similar size copper coil and is obtained by using a Coil wound with HTS (High Temperature Superconducting) wire operated at 50 degK. Priced at $49,000, a complete 5751 System includes the HTS Coil, integral Cryocooler, Compressor for the Cryocooler, Power Supply including polarity reverse and all interconnecting Cables.

February 9, 2004: Oxford Danfysik to build Beamlines for the UK DIAMOND Synchrotron
Oxford Danfysik have been awarded the contract for three complete Protein Crystallography Beamlines for the new DIAMOND synchrotron in the UK. This contract will include design, building and installation of all the main components including adaptive bimorph mirror systems, double crystal monochromators, diagnostics, other standard beamline hardware and an EPICS control system. This contract will be installed in summer 2005.

January 20, 2004: The Institute of Physics announce the publication of 'Hall Effect Devices' by Prof. R. S. Popovic
The Institute of Physics have announced the publication of Hall Effect Devices by Professor R S Popovic of the Swiss Institute of Technology (EPFL) Lausanne, Switzerland. It covers semiconductor physics, operation and applications of Hall devices, including Field-effect and Bipolar types. Professor Popovic is the Founder of Sentron AG, manufacturer of unique Linear Hall Elements and Integrated Circuits and Linear Hall Transducers distributed by GMW. Applications include magnetic field mapping, non-contact position and electric current sensing.

December 16, 2003: Danfysik awarded contract for Injector Assembly
Danfysik has been awarded the turnkey contract for the Injector System of the Australian Synchrotron Radiation Facility at Monash University. Included are: the 100MeV Linac, Transfer Line to the Booster, 3GeV Booster Synchrotron, Transfer Line to the Storage Ring with Injection Septum Magnets, Electromagnets, Power Supplies, Beam Diagnostics and Controls.

September 25, 2002: Sentron's CSA-1V Current Sensor IC wins a Bronze Medal at Sensors Expo
The CSA-1V Hall-effect Integrated Circuit won a Bronze Medal for Sentron at Sensors Expo in Boston. An Integrated Magnetic flux Concentrator (IMC) enhances the CSA-1V magnetic sensitivity to effectively provide lower noise and offset in a CMOS Hall-effect device. Isolated electric current measurement from dc to 100kHz with smaller size, simpler assembly and lower cost than packaged current transducers is anticipated to lead to applications for the CSA-1V to power supplies and motor, generator and power controllers. The CSA-1V is available in SOIC-8 package or 1.9mm square dice form.

September 18, 2002: Danfysik Booster Accelerator commissioned at CLS
The Canadian Light Source (CLS) announced today that the 2.9GeV Electron Synchrotron "Booster" Accelerator has been successfully commissioned in Saskatoon approximately 30 months after the C$8.9M contract was awarded to Danfysik. Beam diagnostic instrumentation for the Booster, including Beam Position Monitors, DC Current Transformer, pulse Fast Current Transformer and Beam Loss Monitors was provided to Danfysik by Bergoz Instrumentation. Danfysik and Bergoz have also delivered equipment for the CLS Storage Ring scheduled for completion in 2003 with operations beginning in 2004.

  March 29, 2002: Bergoz beats the competition
Bergoz Instrumentation announced today the award by CERN for 300+ units of their sensitive Fast Current Transformer (FCT). These high performance FCTs are to be installed in critical locations on the Large Hadron Collider (LHC) accelerator as beam diagnostic monitors.

The specifications for the Bergoz FCTs include:

ID = 38mm
OD = 72 mm
H = 17 mm

Turns Ratio
Type 2 = 100:1
Type 3 = 35:1

Risetime = 30 nsec

Bergoz was selected for superior performance especially for vacuum operations, quality and price.
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  GMW Customer, AccSys Technology, announces delivery of
  PULSAR (TM) Linac for Rome, Italy
May 14, 2001
Dr Robert Hamm, President and CEO of AccSys Technology located in Pleasanton, California, announced the completed delivery of a Model-7E PULSAR (TM) Linear Accelerator to Italy. It will be installed in Rome at the Regina Elena Oncological Hospital to produce the F-18 radio-isotope for use in Positron Emission Tomography (PET) medical diagnostic imaging. In the future the Model-7E will be time-shared as the injector for a linac to produce high-energy protons for cancer therapy.

As well as extensive operational testing and the demonstration of F-18 production, the Model 7E received the European Union CE Certificate of Compliance from TUV Rheinland.

To help meet these demanding performance and reliability requirements combined with an onerous delivery schedule, AccSys implemented a control system based on Group3 Control fiber-optic isolated modules with LabVIEW software and GMW engineering support.
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  NMR Probe Array for fast magnetic field mapping
March 21, 2001
The Metrolab MFC Magnetic Field Camera from GMW Associates is appropriate for very fast, high accuracy magnetic field mapping of uniform field magnets as used in Magnetic Resonance Imaging (MRI), particle accelerator detectors, ion traps or mass spectrometers.

An MFC system consists of an MFC-3045 Control and an MFC-3048 Probe Array configured to the end-user's required geometry. Typically the Array consists of up to 32 proton NMR Probes arranged in a planar array on a semicircle or semi-ellipse. Rotation of the Array about the diameter generates a magnetic field map on the surface of a sphere or ellipsoid. Arrays delivered to date have had diameters of 200 to 600mm. Larger Arrays with up to 96 Probes are possible.

All Probes in the Array are monitored simultaneously and a field measurement is obtained in about 30msec. Normally measurements are averaged for about 2 sec. Then the Probe Array is moved to the next measurement position. A complete map of about 960 points (32 Probes x 30 positions) with about 0.3ppm field resolution can be obtained in less than two minutes.

Recently a new "flat coil" Probe with integrated rf amplifier has been introduced. This has resulted in improved tracking between Probes and an extension to higher fields. Probe Arrays for 3T fields have been delivered and the design is expected to operate to 7T.

  Danfysik announces 400A DC Current Transducer
March 8, 2001
GMW Associates is now offering a new addition to the Danfysik ULTRASTAB Current Transducer product range for ohmically isolated, precision measurement of electric current.

Operating on the principle of maintaining zero magnetic flux in a toroidal core, the 867-400 has a precise 2000:1 current ratio with an output of ±200mA for a ±400A primary current. The transfer linearity is better than 3ppm with a temperature coefficient of less than 0.3ppm/°C. Frequency response of the output current amplitude is from dc to 100kHz (-3dB) with a slew rate of ±200mA/16µs for a step change in primary current. Output current noise is less than 2ppm(rms) of full-scale from dc to 1kHz. Utilizing an appropriate external burden resistor enables voltage signal to be obtained e.g. ±1V full-scale with a 5 ohm burden resistor.

The 867-400 has a mechanical outline of approximately 76mm (3 inch) square by 43mm (1.7 inch) axial length with a large 26mm (1 inch) diameter central hole for the primary current conductor. A dual +15V, -15V (±5%), 250mA power supply is required.

Applications for the 867-400 include current control of particle accelerator corrector and focussing electromagnet power supplies, magnetic resonance imaging (MRI) gradient amplifiers, servo motor amplifiers and current measurement for precision power metering. Compared to resistive shunts or Hall effect current transducers the 867-400 provides greatly improved stability, lower common mode noise, much better linearity, reduced hysteresis and enhanced frequency response.

  Danfysik buys the Synchrotron Beamlines Group of Oxford
   Instruments plc
February 1, 2001
On January 25, 2001 Mr. Michael Russell (left), Finance Director of Oxford Instruments Superconductivity Ltd. and Dr. Bjarne Roger Nielsen, Managing Director of Danfysik A/S signed the final documents for the purchase by Danfysik of the Synchrotron Beamlines Group from Oxford Instruments.

The new company, which will trade under the name OXFORD DANFYSIK, is a wholly owned subsidiary of Danfysik and based at Osney Mead in Oxford.

  Danfysik to deliver Booster Accelerator for CLS

March 15, 2000
Danfysik have been awarded a C$8.9M contract to deliver the Booster Accelerator for the Canadian Light Source (CLS) being built at the Saskatchewan Accelerator Laboratory (SAL) in Saskatoon. The Booster Accelerator will inject 1.5 to 2.9 GeV energy electrons into the main synchrotron radiation storage ring.

  Bergoz completes testing of new FCT

March 15, 2000
Bergoz have completed factory testing of a new Fast Current Transformer FCT with 0.7ns rise time and 0.1%/µs droop. This prototype will be delivered to Brookhaven National Laboratory (BNL) for evaluation as a device to measure the proton beam current pulses in the Spallation Neutron Source (SNS) to be built at the Oak Ridge National Laboratory (ORNL).

  Group3 CNAs chosen for control of SNS H¯ Ion Source

March 15, 2000
At the front end of the SNS project, Group3 Control fiber optic isolated input/output modules (CNAs) are being used for computer control of the H¯ ion source developed at Lawrence Berkeley Laboratory (LBL). The fiber optic communication link enables reliable control and monitoring of electrical subsystems at high voltage and subject to electrical transients.

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