Current distortion after 1A? (powermeter project)

Discussion in 'The Projects Forum' started by Jonesy, Jul 27, 2011.

  1. Jonesy

    Thread Starter New Member

    Jul 7, 2010
    Hi everyone, I've been working on a power meter for a long time, and its the finishing step.

    A problem arises when load above 1A are not accurate. below 1A, everything is measure nice and clean.

    I am using Atmega644p and the analog front end is a 0.1 resistor 15W connected at the neutral to an isolation transformer to a 4th order LPF then to myMCU to measure and calculate data.

    Could it be the isolation 1:1 transformer? i cant find any rating on it.