CIRCUIT ARRANGEMENT FOR MEASURING THE EFFECTIVE VALUE OF AN ELECTRIC SIGNAL

摘要

A measuring arrangement for measuring the effective value of an a.c. signal. Said a.c. signal is applied to a first thermal convertor, while a d.c. output signal is applied to a second thermal convertor. The two thermal convertors differentially drive a differential amplifier, which at its outputs delivers the d.c. output signal. For values of the d.c. output signal which are smaller than a threshold value, a negative feedback signal which linearly depends on said d.c. output signal is applied via an additional negative-feedback network to at least one of the inputs of the differential amplifier. This facilitates zero-point adjustment, and also allows the measuring speed to be increased.