METHOD OF COMPENSATING FOR TEMPERATURE-INDUCED ERRORS IN ALTERNATING CURRENT MEASUREMENT CIRCUITS, PARTICULARLY REMOTE CLEARANCE MEASUREMENT INSTRUMENTS, AND APPARATUS FOR CARRYING OUT THE METHOD

摘要

1. A method of compensating errors caused by temperature changes in A.C. measuring devices comprising measuring means with impedances, in particular for inductive distance measuring equipment with measuring coils forming part of a resonant circuit, characterized in that a constant current having a frequency far below the distance-measuring frequency is supplied to said measuring means additionally to said distance-measuring frequency, whereby a compensated signal (US ) being proportional to said distance is derived from an A.C. measuring signal (Ud ) corrected by correcting signal (Ukorr ) which in turn is achieved by a voltage (UT ) from the output of said measuring means.