illinoiscentral posted:At least two things cause harmonic distortion on the power lines.
- Anything with a motor, and the iron is saturating. Basically a non-linear inductance. I have seen this on scopes when working with power tools, even when the power tool was operated from an electronic AC power supply that re-creates a smooth sinewave. The purpose of the power supply was to maintain 120Vac 60 Hz or 220, 230, 240 Vac 50 Hz at the outlet.
- Anything with a bridge rectifier and a capacitor afterwords, which is just about any modern electronic device. Once the capacitor charges up, until the voltage increases to the point the diodes in the bridge can start conduction, very little current flows. Then alot flows. So its like a non-linear resistor. Once the voltage increases to that point it sags from a sine wave. Same thing happens with our trains with modern electronics, even if a pure sine wave was at the outlet and an ideal transformer.
Wild guessing the cost of making or buying a suitable power low pass filter would exceed the cost of just buying bricks.
Never had a Z-4000, does it have a full on position? Some light dimmers have that, when in the position no triacs in the circuit.
An LPF is a tough one. As a circuit designer I went there immediately too.... but after a few seconds of thinking.... It's not just an RC or LC low pass on a breadboard.... the train draw amps of current, so whatever it looks like would be giant 10-100W rated components that cost a fortune. That time-domain measurement was done at the full position actually.
