The conventional single core or two core saturable reactor or transductor used for dc busbar current measurement may suffer from errors due to the magnetisation component of the dc flux and the asymmetry of the core materials. In the present paper a feedback technique of this type of dc current measurement has been developed. In this technique, the output signal has been used to send a feedback current through a feedback winding in order to nullify the magnetisation component of the dc flux and thus the measurement may be assumed to be more accurate with respect to other similar instruments. The developed network has been studied up to a dc busbar current of 50 A and the output characteristic has been found to be quite linear. The design of the network, its principle of operation and experimental data are reported in the present paper. © 2003 Elsevier Ltd. All rights reserved.