Checkline FH Series User Manual

Page 5

1. Introduction

Designed for non-destructive thickness measurement, the portable MiniTest 7200 / 7400 FH

measuring systems are suitable for in the field or laboratory use. Working on the magneto-static

principle, the gauges enable quick and easy measurement on non-ferromagnetic materials.

The measuring system consists of a handy sensor, which is connected via a cable to the base and

display unit for visualization and processing of readings. For measurement, specially treated target

balls made of a ferromagnetic material are used as a reference. For measurement, a target ball is

placed on the material to be measured so that the material thickness between target ball and

sensor will be measured. The measuring system comes with sensor stand (available as an option)

to add additional comfort of handling during measurement.

For documentation a portable data printer is available. The measuring system may also be

connected to a PC for data communication.

For taking readings, the sensor is placed on the surface of the measuring object, the target ball is

placed on the opposite side of sample. The sensor is placed on the opposite side of sample.

Equipped with a strong permanent magnet, the sensor attracts the target ball and holds it exactly

over its sensor tip. When moving the sensor, the target follows accordingly. The presence of the

target ball will change the magnetic field near the sensor tip. The magnetic field changes according

to the distance between target ball and sensor tip. The change of magnetic field increases with the

distance between target ball and sensor tip getting smaller and can be taken as a reference for the

material thickness of the sample to be measured. The sensor incorporates a Hall element to

capture the change of magnetic field and to translate it into thickness.

For measuring hollow parts, a target ball is placed into the interior of sample and the sensor is

placed on the opposite side in order to attract the target ball exactly over the sensor tip. For taking

readings, the sensor is moved over the surface of sample. For measuring sheets, the sensor is

placed on the surface of sheet and the target ball is placed near the sensor on the opposite side of

sheet. The target ball will automatically center on the correct measuring position and the

measuring processes can be started.

For measuring large-sized parts, the sensor can be guided manually over the sample to be

measured. For measuring small parts, it is recommended to use the sensor stand supplied with the

sensor.

Suitable for use in industrial production areas, the measuring systems MiniTest 7200 / 7400 FH

measure hollow parts, containers and sheet material of all kinds such as bottles, cans, injections

moldings, car bodies, glass, SMC components etc made of non-magnetic (non-ferrite) materials.