There is loss because of the coil, called coil power. There can be significant losses depending on the relay type. Of course these parameters can vary for different devices from different manufacturers but roughly the scale is the same. In case of RX the consumption rises to 56 mA and in case of TX to 270 mA maximum. The CC3200 for example consumes 12 mA if the application MCU is in Sleep mode (not deep sleep) and the Network Processor is in idle connected state. The Wi-Fi will add some more consumption, a couple of mA in its idle state. Most of the time the application processor will be in low-power mode with a current consumption between μA and mA. On the top of these comes the efficiency of the AC/DC power supply, there will be a certain amount of power loss on these elements. The main consumers are the Wi-Fi enabled microcontrollers, the relays and I believe that the LEDs consume more than the metering parts. Some feedback LED and buttons to interface the plug locally.īasically the power consumption of the plug itself is the total power consumption of these parts.A relay to be able to switch the mains lines.There are some dedicated hardware for power measurement.There is a "brain", a Wi-Fi enabled microcontroller unit.There is an AC/DC power supply which provides the DC voltage for the sub-circuits.To do so let's see some smart plug reference designs.Īs you can see the parts of these two different designs are quite the same. To understand better the power consumption of smart plugs it's worth peeking into them.