Abstract: A coating thickness measuring instrument comprising: a magnetic induction probe comprising at least one drive coil and at least one pick-up coil; a driver for driving an alternating current in the or each drive coil; and a detector for detecting the output of the or each pick-up coil; and a processor configured to: apply a transfer function to the detector output to produce an output which corresponds to a measured coating thickness; and, scale both the drive current and detector output simultaneously in response to the output. The scaling may be changed in a step-wise manner. The scaling applied to the drive current may be inversely proportional to the scaling applied to the detector output. The scaling may be defined by a first and second scaling factor, stored as a pair. The instrument may store two or more pairs of scaling factors and select a pair in response to the measured coating thickness.

Abstract: A coating thickness measuring instrument comprising: a magnetic induction probe comprising at least one drive coil and at least one pick-up coil; a driver for driving an alternating current in the or each drive coil; and a detector for detecting the output of the or each pick-up coil; and a processor configured to: apply a transfer function to the detector output to produce an output which corresponds to a measured coating thickness; and, scale both the drive current and detector output simultaneously in response to the output. The scaling may be changed in a step-wise manner. The scaling applied to the drive current may be inversely proportional to the scaling applied to the detector output. The scaling may be defined by a first and second scaling factor, stored as a pair. The instrument may store two or more pairs of scaling factors and select a pair in response to the measured coating thickness.

Abstract: A surface profile measuring instrument has a means for measuring the profile of a surface and a means for storing measurements produced by the means for measuring the profile of a surface. The instrument may have a tip physically coupled to a sensor. The instrument may also have means for processing the measurements and/or for analysing the measurements. The instrument may be connected to an external device such as a printer and/or to a display unit.

Abstract: A dual-mode coating thickness measuring probe for determining the thickness of a coating on ferrous and non-ferrous substrates. The probe has a first winding assembly including an induction winding and two search or pick-up windings and a second winding assembly including a search winding disposed on a non-magnetic and non-conductive former. A magnetic cylindrical pin of a material with a high resistance to impact and abrasive wear passes through the first and second windings. A conductive non-magnetic coaxial screen through which the pin extends separates the first winding from the second winding. The position of the screen is such that it has a minimal effect on the second winding while shielding its field from the first winding. The first and second windings are connected to signal conditioning circuitry which produces outputs representing the coating thickness measured.