Sensor electricity counter


I have 3 phases without N at home. According to another thread it's impossible to correctly measure the current with the clamps. I was wondering if there doesn't exist a sensor that can be attached to the electricity counter. In Belgium there is a wheel whith silver stripes that moves according to the energy consumption. An example can be found at


icarus75's picture

Hi Stijn,

I have been doing some calculations wrt the 230V without N configuration that's still quite common in Belgium and the Netherlands. When the line voltage is set to 133V it will measure a three-phase load correctly (disregarding a cos phi < 1). A single phase load will be read 15% high, and for two-phase loads (e.g. two different lighting circuits active on different phases) the reading will be 8% too high. In view of these numbers, I'd recommend reducing the line voltage parameter by 5 to 10%, so set it between 127V and 120V. While not 'billing grade', the measurements should result in fairly accurate readings that can be used to obtain a good grasp of your electricity consumption.