The present disclosure includes a power measurement, circuit breaker or integrated protection system including isolated analog-to-digital modulators for measuring current using current sensors, such as, for example, current shunts, in a single or multiphase power system. In one embodiment, the modulators are divided into a line-side device with an analog-to-digital modulator and a host-side device including a decimation filter and a processor. In one embodiment, an isolation barrier, such as, for example, a pulse transformer, divides the lineside device from the host-side device.