Helmholtz Coil Systems
Bartington Instruments has now added Helmholtz coil systems to its range. These generate precise magnetic fields ideal for calibration of magnetometers and compasses, and are currently used at Bartington’s own calibration facility.
Helmholtz coils are available in several diameters, from 350mm to 2m. These are supported by a power amplifier and complete control system compatible with every coil in the range. Operating in DC and AC, the three-channel power amplifier delivers up to 29A at DC and frequencies up to 5kHz. Amplitudes and frequencies are coil-dependent, with smaller coils achieving fields exceeding 1mT at DC, and in excess of 100µT at 5kHz.
The control system can be expanded to include a closed-loop control module. This provides active feedback for cancellation of external field variations, making it possible to use the coils in a manufacturing environment. A precise fluxgate sensor is also used as part of the closed-loop system to monitor field disturbances within the coil, achieving field stability of a few nT.
The system may be computer controlled via the addition of a National Instruments™data acquisition card and LabVIEW™ software. By using source code that we provide, you can adapt the software to your exact requirements, enabling seamless integration into your testing and manufacturing procedures.
These systems benefit from reduced orthogonality errors, which facilitates precise calibration of optical range-finding equipment, magnetic field sensors and compasses inside consumer electronics, and magnetometer packages found in oil and gas industry directional drilling tools. The larger coils in the range are suitable for calibration and testing of satellite subassemblies and CubeSats.
In addition to Helmholtz coil systems, Bartington Instruments also provides equipment for magnetic field surveys of proposed installation sites, in order to achieve the best possible system performance.