Inductive pulse inputs, together with an L.C. combination that is built into a meter, form an oscillating circuit. Pulses are generated when this circuit is periodically dampened by a wing wheel that is installed on the meter axis.

IEI Modules are active inputs and supply the detectors in the meter. The signal detector must be isolated (isolated from all ground and all potential voltage connections).

Because the highly sensitive oscillating circuit can be affected by a wire's inductivity and capacity, and by the influx of foreign signals in and around a wire, the secure function of this input can only be assured with a wire length of up to 30cm. For this reason inductive pulse detectors are, for all practical purposes, no longer used.