Connect with us

Non invasively monitor AC backup generator power.

Discussion in 'General Electronics Discussion' started by BobS0327, Apr 29, 2013.

Scroll to continue with content
  1. BobS0327

    BobS0327

    5
    0
    Apr 29, 2013
    I'm putting together a home automation/security package and I want to monitor the power from a Generac automatic standby generator. I want to monitor the state of the power. That is, determine if the power is on or off using a SCT-013-000 non invasive AC current sensor. I would just clamp one of these devices around each leg of the generator power source.

    I would greatly appreciate any info on how to convert the output from these devices into a suitable input for a computer. I was thinking about using some type of USB ADC conversion. I only want to know whether the power is ON or OFF. I don't need to know any type of incremental values. Essentially, I want to verify whether or not the generator is producing power not the quantity of the power etc.

    I was thinking about somehow using this USB voltmeter.

    So, I'd greatly appreciate any info on how to convert the output from the SCT-013-000 to an input suitable to the USB voltmeter.

    Please keep in mind that I have a minimal understanding of electronics. So, please bear with me.

    TIA
     
  2. KrisBlueNZ

    KrisBlueNZ Sadly passed away in 2015

    8,393
    1,267
    Nov 28, 2011
    The voltage-output version will generate a signal representing the load current, which could be acquired by the sound card. It already has the right plug to connect to the line input. You might want to add a couple of diodes across the wires (e.g. two 1N4001 diodes, both connected across the two wires from the current transformer, one in each direction) to prevent possible damage to the sound card. Then run an audio recording application such as Audacity and see what amplitude your sound card shows. Just a suggestion.
     
  3. BobS0327

    BobS0327

    5
    0
    Apr 29, 2013
    That scenario would probably be good for testing purposes. But I'll be using the sound card to make various "security" etc. announcements throughout the home. So, I can't dedicate the sound card for this purpose. If I could translate the AC output voltage into DC voltage and then feed it into the USB voltmeter, this could possibly solve my problem. Thus, no voltage would be an "off" condition and any other voltage would indicate an "on". The problem is that I don't have enough electronics knowledge to design this basic rectifier circuit.

    Thanx for your suggestion.
     
  4. KrisBlueNZ

    KrisBlueNZ Sadly passed away in 2015

    8,393
    1,267
    Nov 28, 2011
    You won't be using the sound card input when you make announcements...
     
  5. BobS0327

    BobS0327

    5
    0
    Apr 29, 2013
    Duh. I guess I just wasn't using my head. I am at loss as to how to input to the sound card the two sensor outputs, (two legs of the generator "mains") since each leg of the generator has an independent circuit breaker. One breaker may be tripped and the other breaker may not be tripped.

    Also, writing .Net code (C#) to monitor the sound card input may be a little challenging.

    The ultimate goal of this project is to send text messages and emails to various people to inform them when the generator starts/stops and to verify that both generator legs are supplying power.

    Thanx for your response
     
  6. KrisBlueNZ

    KrisBlueNZ Sadly passed away in 2015

    8,393
    1,267
    Nov 28, 2011
    The sound card has two inputs - left and right. Yes, you would have to write some code. I'm not saying it's the best solution, but I think it could be made to work.
     
  7. BobS0327

    BobS0327

    5
    0
    Apr 29, 2013
    I checked my onboard audio card and I don't see any left and right inputs. I only have a line input and a microphone input. From what I can gather thru my internet searches is that the left and right output is combined into one PC line input. That is, I've seen cables on the internet with two RCA phone jacks merged into on 3.5mm mini jack for a PC line input connection.

    All three of my desktops only have a 3.5mm connection for Line input and Microphone input. All the other audio ports are designated as output ports.

    Maybe I'm missing something but I can't figure out how to make this work.

    Thanx
     
  8. BobK

    BobK

    7,671
    1,681
    Jan 5, 2010
    The jack has 3 connectors, left, right and ground.

    Bob
     
  9. BobS0327

    BobS0327

    5
    0
    Apr 29, 2013
    Bob, thanx for the clarification. Essentially, I have to merge the two sensors into one 3.5mm mini jack which isn't a problem.

    I'm just not sure I want to invest the time and effort into writing a basic "oscilloscope" application to monitor both sensors.

    Thanx everyone for your help.
     
  10. BobK

    BobK

    7,671
    1,681
    Jan 5, 2010
    You can get the oscilloscope software as freeware I believe.

    Bob
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-