' Smartmeters' | Model Engineer
.....please enlighten me how these work ? Its all done in an integrated curcuit (IC). Voltage measurement is straightforward, simply a potential divider across live and neutral. Current measurement is done using a current transformer. These are a toroid with a multi-turn secondary. The primary, carrying the current to be measured, is a single wire through the centre of the toroid. A load resistor (usually a few tens of ohms) is connected across the secondary. The current in the load resistor is...
Source: model-engineer.co.uk