Before I begin this project, I need to see if what I want it to do is actually possible. I have a wood shop in my basement. Stationary equipment includes: dust collector, table saw, router table, CNC router, miter saw, planer, and jointer.

An example of what I want to do; I turn on the table saw the dust collector turns on then sends power to a solenoid that opens an air switch to open the blast gate the table saw is connected to. Then when the saw is turned off the dust collector runs for 10 seconds longer then turns off and closes the blast gate. Pretty simple… but, here is an issue. Let’s say I have the CNC router working on a project. The dust collector needs to remain on and the gate open for CNC router even if I turn the table saw on. So, it needs to disregard the power on of the dust collector and the delay but still close the gate to the table saw when it turns off.

I know I will need something to see power usage from each piece of equipment (hoping someone could point me in the right direction) and use relays to control the dust collector and probably the solenoids for the air valves since they are 48v.

Is this something that is feasible or am I outside of the capabilities of an Arduino? I have limited experience with Arduino, I played around with some LEDs a few years ago but have done some other coding in other languages.

Thanks for any guidance, Matt

This is all entirely within the capabilities of your arduino.

And you won’t disregard the the power off of concurrent devices. You will use all inputs to decide what to do.
pseudo code might look like this:

-read all your inputs
-if any devices are running and the dust collector is not running, start the dust collector
–also clear any noted time used later for power off condition
-for each running device, if its blast gate is not already open, open it.
-for each non-running device, if its blast gate is not already closed, close it
-if all devices are off, and the dust collector is running and you have not already noted the time, note the time.
-if you have noted the time, and more than 10 seconds has elapsed and the dust collector is running, stop it.

Awesome, that does make sense. Thanks! I will delve further into this now that I know it is something that is possible.

Anyone know what would be best to use to "see" what equipment is on? I was thinking a split core sensor but I think I would run into problems with that if I am using a palm sander that is on the same circuit as say the miter saw since all those outlets are in series. Am I right? Plus, I don't think there is enough room in the outlet box since the core has to be around one wire.

I thought about using a smart plug that has IFTTT capabilities but in my experience with smart things in my house there can sometimes be a long delay with cloud based connections.


So you have two things to figure out (not counting CODE :-)

SENSE when a tool is turned on

CONTROL POWER to gates etc.

Easiest way to sense 120 VAC is to have it activate a small 120V AC coil relay. The use the relay contacts like a switch input to Arduino. If you want a more off-the-shelf solution see these: http://www.digital-loggers.com/ac.html |500x451

Control Power: Use opto-isolated relay modules. See: THIS LINK

Or use an off-the shelf solution like these if you need to control 120VAC: https://dlidirect.com/products/iot-power-relay |500x245

Depends on cost, how much you are willing to dig into the power stuff etc..

although it is fun to use an Arduino for this sort of thing, shop guys have been doing this with relays and switchs for a very long time.

all machines would have an on/off switch. all tied into the dust collector.
any one on will have it run
when the last one is off, the timer starts and shuts the unit down.
manual button on the wall for the floor mounted sweeping vent.

if you added a CT or current transducer to each unit, specifically the motor, you could monitor motor amps.
you could data log the run time and display voltage, watts, amps, etc and even alarm if out of range.

and if you don’t mind buying the parts.

I do not know how far you can run wires from a CT and if your shop has one machine 50 feet As The Wires Run.(ATWR) away from another, then you probably need to get one Arduino for every machine that is more than 6 feet (ATWR) from the next.

If every machine is run from a dedicated circuit breaker, then you can do the whole lot near the electric panel.

Thanks everyone for the help. I think I have a direction to go. I ordered one of the power sensors to try out and see if it will work for my needs before I order a bunch of them. Thanks again!