DX-3HF Three-Axis Helmholtz Geomagnetic Compensation System

1 geomagnetic compensation coil 2 Magnetic field intensity:-1mT~1mT 3 Resolution:1mA, Stability:0.05%; 4 with RS232 interface

DX-3HF Three-Axis Helmholtz Geomagnetic Compensation System

1. Coil Size

Coil frame processed and spliced by non-magnetic hard aluminum alloy LY12. Then it is sealed by sealing plate after coiling. The width of coil frame is 30mm × 20mm. The width of slot is 12mm and the depth is 10mm. The size of inner frame is 320mm × 320mm. The middle is 360mm × 360mm, and the outer is 400mm × 400mm.( Following diagram shows)

1) Along the front-to-rear direction, side length of the designed coil is 400mm × 400mm;

2) Along the horizontal direction, side length of the designed coil is 360mm × 360mm;

3) Along the left-to-right direction, side length of the designed coil is 320mm × 320mm;

4) The Intermediate is platform processed by non-magnetic hard aluminum alloy LY12. The size of the platform is 100mm×100mm×15mm;

5) Reference coil images (size 800mm)

 2. Coil Homogeneity Area

1) Requirement of the coil homogeneity area: 50mm × 50mm × 50mm;

2) Homogeneity (calculated by the smallest group of the square coil): 0.5%; (if the homogeneity requirements are higher, the coil must be enlarged)

3) Magnetic field intensity: -1mT~1mT

4) Resolution of the magnetic field consistent with the power, reaches 500nT, stability and accuracy are better than 1μT;

5) If need higher resolution, a more precise power or the auxiliary coil with more than one power supply should be adopted.

3. Power Description

1) The power suppluy with 232 serial communications is adopted, to achieve full computer program controlles constant current output and directly reach the desired magnetic field;

2) Power: 30V/3A, Resolution: 1mA, Stability: 0.05%;

3) Output: programmable constant current output;

4) External serial AD / DA can be controlled and operated by software on the Laptops;

5) Design of corresponding: 2A corresponds to the full-scale 1mT.

4. Measurements of Environmental Magnetic Field

Environment magnetic field is measured by three-dimensional magnetic fluxgate. Magnetic field measurement range: ± 99999nT, resolution 1nT, noise 1nT, accuracy < ± 1.0% FS. Products meet GB6944-2005 and constant weak magnetic field calibration standard NIM-04-03-2003 technical requirements. Liquid crystal display, conversion rate is 1.5 seconds / second. RS-232 communication interface is full-duplex.

Explanation: Fluxgate magnetic field is only used to measure the environment. It can transfer the three-component magnetic field digital to the PC by serial port conversion card, and can maximize the effective compensation of the geomagnetic field. If need compensate fully, please give the relevant technical requirements to be convenient for the selection of a more precise power or auxiliary coil with power supply to realize. Fluxgate Instrument limits the measurement range. If magnetic field exceeds the measurement range, the valve of magnetic field depends on the completely linear coil and power’s guarantee.