List-Magnetik Ferromaster Permeability Meter

List-Magnetik Ferromaster Permeability Meter

Determines the Relative Magnetic Permeability Easily with a Measuring Range of µr = 1.001 to 1.999

Easy Measurement

The FERROMASTER is a compact, hand-held instrument made for easy measurement of relative magnetic permeability of materials and workpieces with µr between 1.001 and 1.999. The relative permeability is measured by touching the workpiece with the sensor tip and reading the result on the LCD display. The permeability probe contains a small permanent magnet which magnetizes the sample by the probe tip, which then gets read by two sensitive magnetic field sensors and measures the distortion of the magnetic field introduced by the magnetized sample. Calibration can be easily readjusted. The FERROMASTER comes in a robust waterproof case (protection IP65) and is well suited to applications in harsh environments. The built-in battery serves for approximately 50 hours of operation.




  • Easy to Use
  • Measuring Range µ = 1.001 to 1.99
  • Permeability test in conformance with ASTM A342 and EN 60404-15.
  • Calibrated to reference standards of the National Physical Laboratory, UK.
  • Calibration material supplied
  • 31/2" digit LCD Display
  • Automatic zeroing
  • Waterproof enclosure (protection IP-65)


  • Quality control of stainless steel
  • Non-destructive testing of materials and workpieces.
  • Material selection for electron / ion beam equipment and NMR instruments.
  • Detection of ferromagnetic inclusions in materials.
  • Investigation of magnetically anisotropic materials.
  • Detection of material defects induced by stress.

How it Works

The magnetic permeability of a material generally depends heavily on the strength and frequency of the magnetizing field. The probe head of the Ferromaster contains a permanent magnet that generates a constant magnetic field of around 35 kA/m (440 Gauss) at the test probe. Ferromaster works with a saturation core and 2 alternating field coils according to the fluxgate principle and can measure permeabilities in the measuring range between 1.001 and 1.999. Above this measuring range, the saturation cores are too saturated and no longer result in a linear measurement. The measured value of the permeability depends on the dimensions of small samples. The sensitivity of the device is effected by the thickness of the sample. From a sample thickness of about 5 mm (0.200") and a lateral extent of around 2 cm (0.800"), the measurement is independent of the size.

Meter Comparison Chart

Specification FerroPro FP-5 Ferromaster
Range μr = 1.000 to 5.000 µ = 1.001 to 1.999
Accuracy High Standard
Memory / PC Interface Yes No
Rugged Probe and Probe Cable Yes No

Technical Specifications

FERROMASTER Specifications

Measurement Range µ = 1.001 to 1.999
Resolution 0.001
Display LCD 3 1/2 Digits
Accuracy of Calibration @ 20 °C (µ-1) x 5%, reference to NPL calibration standards, can be readjusted
Operating Temperature 32 °F to 122 °F / 0 °C to 50 °C
Field Strength at Probe Tip ~35 kA/m
Battery 9V (PP3, Alkaline)
Operation Time with 1 Battery ~50 hours
Unit Dimensions 6" x 3.2" x 1.3" / 151 x 82 x 33 mm
Length and Diameter of Probe 1.3" x 0.7" / 35 mm x 19 mm
Environmental Protection IP65
Connection Cable Length 59" / 1.5 m
Weight 0.6 lbs. / 280g


(Dimensions of the permeability probe in mm (subject to alterations)

Kit Includes


  • Ferromaster Magnet Permeability Meter 
  • Probe
  • Calibration Standard (Available in Ranges: μr = 1.03, μr= 1.11 or μr = 1.35)
  • Case
  • Calibration Certificate
Description Part # Saved Price Select Option Add to
Magnet Permeability Meter / Ferromaster with Probe, Calibration Standard and Case (Old PN: 7350)(Specify Calibration Standard Range)
Model #
MI-LM-3110-Master $2,150.00
Calibration Standard for Ferromaster and FerroPro FP-5 (Old PN: 7353)(Specify Range)
Model #
MI-LM-3170-Master $335.00
Ferromaster Factory Recalibration (shipping not included) MI-LM-FERRO-CAL $275.00