Help with Sound activated relay

I want my shop vac to turn on whenever I turn on a loud power tool in my shop. I thought it would be interesting to trigger it with sound using this microphone sensor.

It seems pretty straight forward to activate the shop vac with the sensor and a relay. I was thinking myself quite clever for the idea but then got stumped on how to deactivate the relay when the tool turns off. At that point the shop vac will also be making a ton of noise and the sensor won't know the difference.

Any ideas to make this work? I'm open to using another method as well.

I see it has an analog output. Does the level vary enough that you can tell the difference between tool and vacuum and just vacuum?

You might consider how long you run a tool for and just turn the vac off after say two minutes. You can always restart it after a short delay if there's noise.

As you probably know, most people do this by detecting that a tool is pulling power using a current detector.

Thanks @wildbill . I measured and my table saw runs at 83 db and the shop vac runs at 81db. Not sure if the sensor is sophisticated enough to differentiate that small of a difference. Maybe if the sensor were a lot closer to the saw.

Yeah, I may end up going the current sensor route. I liked the idea of activating the shop vac even if it wasn't plugged into the same thing as the tool. Then I could use it with multiple tools.

It would be nice to have it sound controlled - you could even turn it on yourself if you could shout loudly enough :grinning:

In the projects I've seen that do this, it's usually combined with automated blast gates. Sometimes there's one Arduino for each tool or two, others use a single Arduino and run wire to every tool. The one thing that doesn't vary is the use of current sensors.

When I get around to doing this, I'll probably use several ESP32s or Wemos D1 minis and let them use WiFi to talk to another unit that controls the cyclone.

Or sneeze...fart. Could be quite a surprise. :sweat_smile:

"Alexa turn on the the vacuum please"
"I'm sorry I cannot turn on a perfect vacuum, please rephrase your request"
"Alexa turn on the fr%&%$ing vacuum!!"
"Oh the fr%&%$ing vacuum, okay"

Tom... :grinning: :+1: :coffee: :australia:

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