Products

Reference Magnets

Data Sheet Datenblatt

Description Reference Magnet VM 4

For the simple calibration of flux meters and field strength meters MPS has several reference magnets available. The field range from about 0.05 T to about 1 T is covered with the "transverse" reference magnets.

One model which stands out in the product range is surely the reference magnet VM 4, developed especially for maximum measuring accuracy. This magnet system for the calibration of transverse measuring systems produces an air gap induction of 0.2 T or 0.25 T in an air gap of 10 mm. The homogeneity of the magnetic field in the air gap is so great that the calibration of the system is carried out with a nuclear magnetic resonance measurement (NMR).

The reference magnets are available in the following standard configurations:

Article- Number	Article- description	Air gap	Air gap Ø	Field strength in air gap	Induction in air gap
100 612	VM-4-2mm-1T	2 mm	20 mm	800 kA/m	1 Tesla
100 613	VM-4-5mm-0,5T	5 mm	35 mm	400 kA/m	0,5 Tesla
100 614	VM-4-10mm-0,25T	10 mm	50 mm	200 kA/m	0,25 Tesla
Dimensions (length x width x height mm): 120 x 80 x 90 Weight: 2,2 kg ATTENTION: fixed air gap distance!

MPS can issue DKD or proprietary calibration certificates for the reference magnets so that customers can check their measuring equipment themselves on site.

Description Reference Magnet VM 5

The reference magnet VM 5 is suitable primarily for the calibration of axial probes. These can have a diameter of up to 6 mm. A side insertion allows additional testing of transverse Hall probes.

The VM 5 has extraordinary good homogeneity for an axial reference magnet, so much that the field strength can be given to 0.3 % exactly.

The reference magnets contain highly stable permanent magnets that have low temperature coefficients.

The flux densities and field strengths given in the tables are approximate values. The exact values are determined when the reference magnet is calibrated shortly before delivery.

Axial acceptance	Transverse acceptance	Field strength	Flux density
6 mm	5 mm x 10 mm max.	80 kA/m (1 kOe)	0.1 Tesla (1 kGauss)
Dimensions: Diameter: 68 mm, Height: 55 mm Weight: approx. 1 kg ATTENTION: fixed air gap distance!

A proprietary calibration certificate is issued free of charge on purchase. A calibration can also be carried our in our accredited DKD calibration laboratory. Periodic recalibration is recommended and can also be carried out by our laboratory, of course.

To preserve the calibration accuracy over a long time, we recommend to observe the following precautions:

• Keep standard magnets away from magnetic fields.
• Do not insert magnetic or magnetizable parts, e.g. tools, into the air gap.
• Avoid magnetic pollution in the air gap.
• Store the standard magnets in a safe place and take them out only for the calibration of your measuring instruments.
• Do not expose the standard magnets to mechanical shock or extreme temperatures.