Does anybody have or suggest pictures, videos or schemes about the making of a vacuum pump controller?
Do you want to control the vacuum or the pump?
Joewoodworker.com has a decent controller. Also has several good diagrams and setups using MAC valves to help prolong pump life. Only down side to their controller is that its max vacuum is 28”.
I made one from a used SMC pressure switch (I think an ZSE30), a solid state relay and a power supply. Since I am based in China, where they scrap a lot of electronics, I could get the SMC pressure switch for about 20 bucks. The rest of the stuff was cheap as well.
The switch lets you set hysterisis and target pressure. Just make sure you get a switch that is suited for vacuum. It has worked flawlessly despite me not knowing anything about electronics, really. So, I can’t walk you through the setup as it was a mix of googling and trial and error.
If you are interested in this approach, I would download some datasheets of the controllers for research and start looking on Ebay. I would not hesitate to buy an older unit or older series. IIRC the newer series may be called 40 series and the older one 30? Also, some of them only display one kind of units while others let you choose units. While physically the same size, they will have different mounting options for different sizes of tubing but that’s pretty easy to work around. Do try to get one with the cable, though so you don’t have to source that on its own.
If I was do to it again, I would possibly make an arduino based one. A few of the radio controlled guys have come up with what looks like some cool solutions.
This one may be the most developed and supported:
Searching through my laptop, I found an old reply to a member of a different forum which asked about my setup, so I will C+P my reply here with some added notes :
Mine was done on the cheap for sure.
We will get back to the switch, but the pump is the smallest, cheapest vac pump of the kind the AC/refrigeration service guys use. These days I buy everything on Taobao but the pump I actually got from a “real” shop and I got to run it. Turned out it pulled slightly better vac than the bigger ones. Might just have been coincidence.
Wait, let me backtrack. I basically did my pump based on the Joe Woodworker pump (google it) but I went without the smaller pre-reservoir and solenoid (which gives the pump an easier startup with no pressure on the pump). While I did leave some things I upgraded to a better switch (the SMC).
But it does have a reservoir. Here, I used the smallest air compressor tank I could get. If I did it now, I would probably just make one out of PVC pipe as they do in a lot of the Joe Woodworker builds.
Now, as for the switch. You do need the ZSE series as that is the vacuum models. Mine is an ZSE30-01-25-M. Which I think is an NPN switch without unit switching. The latter means that it can only show one type of units. In this case, it’s kPA, but it is easy to get the hang of as -100kpa is 1bar of vacuum, so I just think of the display value as a percentage of full vacuum ([EDIT] I know “full vacuum” is a misnomer but let’s not get into that here).
Download the datasheet if you haven’t already as there’s also a version where you can switch to other units. I think it might be call N instead of M. But it is harder to find used.
The rest have to do about what size tubing it takes but just consult the datasheet.
The switch needs to be powered. It runs on 12-24V, I think and it needs a relay, since it can’t turn the power to the pump on and off directly. So, basically, you power it with a small, cheap power supply and then send the on/off switching signal to a solid state relay which in turn, switches the pump on and off.
Notes on this pump after having used it for a few years:
It was built to be small, cheap and portable for hobby use. It weighs only 7kg and has performed great. But the HVAC service units have oil in them so you have to be careful not sucking that into the bag and probably breathing the misty oil it spits out is not healthy either. that
I feel that it is getting a bit tired now, but not sure why. Maybe incorporating the sub-reservoir and solenoid as Joe Woodworker’s plans call for is not a bad thing after all. It protects the pump on start up (their PDF explains it well). I only have a one way mechanical valve but no sub-reservoir.
The controller side of things has worked great from the get go.