Extraction Automation Complete!

[boyd]

Thanks to all who helped with advice on this system. Now when I press the start button on my thicknesser, buzzer, table-saw, my dust extractors start running and a pneumatic gate opens. When I turn the machine off, the extractor continues running for 30 seconds and the gate closes.

I used a very simple time-off delay using a capacitor, npn transistor and a relay.

The extractors are controlled with 80A SSRs

I have two relay boards to accept a closed circuit from each machine which holds a small power supply and relay. This to avoid any wires running in my workshop with high voltage.

If you are interested, I uploaded a video to youtube.

I am very happy this all came together. Once again thanks to all who gave me the advice I needed. Oh and the birds-nest inside my enclosure will be sorted lol. I also attached a picture of a basic setup that I might try out on the market. Ha

 

[shrtrnd]

Thanks for sharing your success story. Guys here who helped you with it will be pleased.
(A lot of times, people take our advice, make their problem work, and never tell us their success).

 

[CDRIVE]

Very nice but I'm curious why the dust collector remains running for a full 30 seconds after the blast gate is closed?

Chris

 

[boyd]

Hi Chris,

Because it is a woodworking workshop it is very common to switch machines rapidly. So I put in the 30 second delay to avoid the extractors that are both 2.2kw from stopping and starting. I have found though I need to install a similar circuit to delay the start of the extractors by a couple of seconds as my thicknesser and the two machines starting at the same time will trip the under voltage in the KJD12.

Currently designing the circuit now but am getting strange outcomes. I pulled it off the net and am playing around with the cap and input resistor values because its not quite correct. Somehow the cap is not draining fast enough on "off" as well as no real delay when "on"

 

[boyd]

Eeeh! Im just going to cheat and buy this lol

https://www.aliexpress.com/item-img...01955.html?spm=2114.10010108.1000017.1.wh62dS

 

[CDRIVE]

Eeeh! Im just going to cheat and buy this lol

https://www.aliexpress.com/item-img...01955.html?spm=2114.10010108.1000017.1.wh62dS

That's not cheating. It's being practical. It's hard to beat or even resist those Chinese modules. China sells a plethora of electronics products targeted at electronics enthusiasts and DIY'rs. I'M A CHINA'S EBAY ADDICT!! You couldn't buy the individual components or even the bare PCB (alone) cheaper than that.

Chris

 

[chopnhack]

Well done Boyd!

 

[hevans1944]

Yeah, $2.55, even with shipping and handling added, is a no-brainer. Good find @boyd!

 

[boyd]

Hi Guys!

Hey I needed to post this small piece of info. I actually, one night whilst in bed thinking. Realised I had wired the KJD12 incorrectly. I wired the input to the output. This in turn caused the latching solenoid to be always powered when the button is depressed. The undervoltage protection is still there but if left the switch continues being in the latched state and gets warm.

Just to clarify, I have the KJD12 connected prior to two SSRs controlling the on/off of my extractors.