create and capture a transient

Discussion in 'The Projects Forum' started by chaosmc, Jul 4, 2012.

  1. chaosmc

    Thread Starter Member

    May 21, 2012
    Hi everybody,

    The title is my question! I have an ac-dc converter for example and it is working all right in the steady state! I want to create a voltage sag, spike or surge in my input voltage and see the behavior in my output.

    So, how can i create and inject this spikes or other transient phenomena in my input voltage and on the other hand how i capture them on my oscilloscope?

  2. WBahn


    Mar 31, 2012
    The capturing part depends on the capabilities of your scope. The creating part would depend on the kind of transient you are trying to do. For some of them I would imagine you could use a transformer, along with some switches and power resistors, to inject them. You can probably get spikes using some inductors.

    You might want to use an isolation transformer to get from your main power to your setup so that you aren't directly fighting the utility company -- they tend to win those battlres. If you want a significant excursion, you probably need to use more care.
  3. wayneh


    Sep 9, 2010
    +1 My favorite is to use free signal generator software on an iPod to generate square, triangle and sine wave tones in the audio range. Guitar tuners do much the same thing, although usually limited to square waves at fixed frequencies.

    if you just want a slight sag at "DC" (very low) frequency, I'd just set up a resistor voltage divider and switch between Vcc and 0.9Vcc, or whatever level of sag you need.