Which Probe should I use?

With Hirst Gaussmeters, there are several probe options. Depending on your application, you may need a different probe to the TP002 Standard Transverse probe, which comes with every new GM07, GM08 and GM09-1 Gaussmeter.


The GM09-3 uses the 3DHS-1 probe.

If you are looking for probe specifications, please see our range of probes here.


Axial or Transverse?

These two simple animations show the correct use of each probe.


Transverse Probes

TP002 (Standard Transverse Probe), TP002HS (High Sensitivity Transverse Probe), TP002R (Rugged Transverse Probe), TP002SP0.6 (Extra-Slim 0.6mm Transverse Probe)



Axial Probes

AP002 (Standard Axial Probe), AP002HS (High Sensitivity Axial Probe)


Do I need an AFG100 Fluxgate Probe?

The AFG100 Fluxgate Probe is specifically for detecting and measuring very 'low' magnetic fields. Unlike the Axial and Transverse probes, which are best used in direct contact with the surface of a componenet, or in air gaps or coils, the Fluxgate probe is designed to be pointed at the item under inspection from a distance. 

This is why it is ideal for applications, such as:

  • Material and package inspection in line with CAA policies
  • Measurement of local magnetic fields. 
For the measurement ranges of the Fluxgate Probe, please see below.


Sensitivity and Ranges

Each probe has a specific capability to detect magnetic field strengths and magnetic flux density within a certain range of measurements. To decide which probe is best for your application, make sure you have an estimate of the measurement you expect. If it is likely to be a high reading, as standard sensitivity probe should be appropriate. 

See the tables below to compare the ranges of each probe type.


Standard Probes (TP002 and AP002)

Please note that the TP002R (Rugged Transverse Probe) and the TP002SP0.6 (Extra-Slim 0.6mm Transverse Probe) have the same ranges of measurement as the TP002.


TeslaGaussAmp/mOersted
Range 13.000 T30.00 kG2388 kA/m30.00 kOe
Range 2300.0 mT3.000 kG238.8 kA/m3.000 kOe
Range 330.00 mT300.0 G23.88 kA/m300.0 Oe
Range 43.000 mT30.00 G2.388 kA/m30.00 Oe


High Sensitivity Probes (TP002HS and AP002HS)


TeslaGaussAmp/mOersted
Range 130.00 mT300.0 G23.88 kA/m300.0 Oe
Range 23.000 mT30.00 G2.388 kA/m30.00 Oe
Range 3300.0 µT
3.000 G238.8 A/m3.000 Oe


Fluxgate Probe (AFG100)


TeslaGaussAmp/mOersted
Range 199.99 µT999.9 mG79.60 A/m999.9 mOe
Range 29.999 µT99.99 mG7.960 A/m99.99 mOe
Range 3999.9 nT9.999 mG796.0 mA/m9.999 mOe
Range 499.99 nT999.9 µG79.60 mA/m999.9 µOe