Author Topic: Power Meter for Variac  (Read 2271 times)

0 Members and 1 Guest are viewing this topic.

Online ledtester

  • Super Contributor
  • ***
  • Posts: 1434
  • Country: us
Re: Power Meter for Variac
« Reply #50 on: April 16, 2021, 09:06:11 pm »
The Peacefair units use the V98XX series of energy metering SoC chips:

Update: In section 18.3 (physical page 275) of the V98XX datasheet there are some tables showing the update and settle times of the metering registers along with this note:

... In 60Hz power grid, the time for updating and settling is 1.2 times of that for 50Hz power grid. ...
« Last Edit: April 16, 2021, 09:36:28 pm by ledtester »

Online coppice

  • Super Contributor
  • ***
  • Posts: 6306
  • Country: gb
Re: Power Meter for Variac
« Reply #51 on: April 16, 2021, 09:16:08 pm »
I also find the chinese power meters have very long averaging time in firmware, it takes a few seconds to get a settled reading with a constant load. They aren't useful for fast response unless you communicate directly with the IC.
I wonder if that's because they use cheap/slow parts and a low sample rate?
Its because they use the cheap, but quite accurate, devices made for the utility energy meter market. That market cares about accuracy over a wide dynamic range, but not about the update rate.

Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo