I am in the process of building a dust collection system, or shop vac or whatever. Anyway I'm soon going to have suction to all my tools ( finally) but I'd love to have the suction to turn on when I turn on any tool!
I have lots of power tools, one phase tools are bandsaw, belt sander, bench grinder, planer and others. Three phase tools are circular saw and drill press.
So any idea how to acomplish this? Pic is related, there would need to be a switch somewhere downstream from such as lighting and handheld power tools that would turn on the suction automatically. With one phase and one plug it would be easy the 3~ seems to be a bit trickier. I tried to search but couldn't find anything for more phases than 3...
And I live in 230V-land, three phase motors use 400V phase-to-phase voltage. As 3~ needs phase-to-phase the sensing would be needed between those, not between phase and neutral...
Anybody have plans for my idea?
You need a current sensor on each phase. Like a clip on loop thing that goes around each wire somewhere. And a controller that operates a contactor when current is detected anywhere
Just hook it up to a light switch that also runs a ceiling fan or other dust control measures. No harm in it running a while extra. Maybe try to make one of those "cyclone" dust collector things to keep the shop vac filter clean
you need something like this.
Nimm den Rückleiter; Der ist ja bei allen gleich, so umgehst du das Problem mit den Phasen.
Elegant wäre dann eine Strommesspule ( Linearer Stromsensor, 15 Euro), der ne Spannung induziert sobald du dein Werkzeug nutzt. Das ganze dann über einen Transistor zu einem Relais, am besten ein SolidStateRelais und voila - fertig.
> You need a current sensor on each phase
dont think so. when the motor is off, all three phases have zero current, when it's on, all three have current. so, monitoring one wire is sufficient. unfortunately, you need quite a number of turns to pick up a good-enough signal. a current clamp uses few turns but it has a laminated iron claw to amplify the magnetic field around the wire.
a better plan might be to use a hall switch to detect the motor's magnetic field, or one of those suction-cup telephone recorder magnetic pickups. another option is an IR proximity detector pointed at some moving part, like the shaft, painted with a stripe, or the motor's fan blades.
Take the neutral / return conductor; so you don`t have to worry about the phases.
Best idea would it be to use a coil for inducting a few Volts. Thenuse a transistor to run a Relais. (SSR)
Use three of these guys ( https://www.sparkfun.com/products/11005 ) plus a microcontroller.
Buy them from somewhere else that's not sparkfun.
Don't bother with being too clever, just calculate the total current draw, then subtract what you've measured the dust extractor to use if it's switched on. You certainly could make it work like in OP, but then you'd have to change the code whenever you got another tool.
Obviously you'll want to be using an optoisolated relay; buy that as a board unless you're confident mixing your own home-designed and built electronics with mains electricity.
I do indeed have a cyclonic sucker. It started out as a vacuum cleaner with a plastic can. Now it is a steel behemoth that can turn on a LADA by sucking from the tailpipe. Noisy but highly effective.
Ich sprechen nicht Deutsch. Alles meine deutch ist:
Habst du lust? Nein, ich have Kopfsmertchen.
This linear current sensor needs to be investigated if it is a thing.
You are correct. Phase-to-phase. Then you get the extra oomph provided by 400V. Without the 3~ this would be much easier...
This seems promising. I'd like to avoid microcontrollers if it's possible as I know nothing of them. I'm more of a weld it screw it nail it drill it of a type. But if it's unavoidable...
Maybe you are talking about the same as >>934741
if you read the op you would know there is a mix of 3 phase and single phase.
not for 3 phase necessarily.
its not impossible, you could probably do something with linking a few control modules together but getting it to ignore the extractor might be difficult unless its on its own phase.
There exists a product that is a hose gate that whenever you open the gate, your dust collection comes on. So ideally you'd have every gate closed then open the gate at the machine you're working at, then only 1 gate is open and you're maximizing your suction. TheSamuraiCarpenter installed them in his new workshop, he mentioned it in a recent vid I think. Can't remember the name of the product though
Microcontrollers are the lego of computers.
If you can explain what you want done to an complete idiot with no common sense whatsoever, who will nevertheless do exactly what you say in the exact way you said it, you can program a microcontroller.
For just about any application, someone will have made a prefabricated board that you just plug into an Arduino, so you don't need to do any electronics unless you want to.
Won't that latch on, as the extractor relay will get actuated by the extractor motor's current draw?
One of these days I'll remember to attach the picture with the post.