4 ms·

I recommend getting a plug in energy meter. You can get an accurate reading for any device with it. I'm currently using mine to figure out why were still using

• jhoelzel 4y ago
  Maybe this wont help you much, but I am currently looking into the shelly 4 pm, which goes directly into the fuse box and can measure the power consumption on 4 fuses (and trigger them)
• hanche 4y ago
  I have been wondering about that. Are these meters built on the assumption of a purely resistive load, or will they give accurate readings even with a switch mode power supply? My very limited understanding says these draw current in a very different pattern than a resistive load. The meter would actually have to integrate voltage×current to be accurate, I think.
  • mrob 4y ago
    Most of them report power factor, which requires measurement of reactive loads.
    • hanche 4y ago
      Thanks, that is helpful to know. However, a switch-mode power supply is quite different from a reactive load. Cheap ones tend to draw power only near the voltage peaks, whereas better ones improve on that. See [1] and [2]. So the question remains how well these cheap power meters cope with such a nonlinear load. [1] https://en.wikipedia.org/wiki/Switched-mode_power_supply#Power_factor https://en.wikipedia.org/wiki/Switched-mode_power_supply#Pow... [2] https://en.wikipedia.org/wiki/Power_factor#Power_factor_correction_(PFC)_in_non-linear_loads https://en.wikipedia.org/wiki/Power_factor#Power_factor_corr...