all that smoke in my basement is killing me! [smoke from the fridge pump]
how can a simple guy make a regulator that turns the electricity on and off at 0.25 bar of vacuum?
that pump should stop now and then, so the smokes are kept down, and the pump doesn-t overheat either [something that happens with the RR slow hardener]
i have absolutely no idea, and the search for vacuum switch, or vacuum regulator doesn’t give my anything to work off
I built a system like this, but instead of the switch turning the pump on or off directly, it trips a relay that turns the power on or off. I had problems finding a switch that could handle the amount of current the pump needs, but when i used $10 relay rated at something like 3A it works great. Once the bag gets to the vacuum level you set using the spring adjustment, the pump turns on every 5 minutes for 1 or two seconds at a time, when I get a really good seal on my bag. The bigger your vac resevior, the more efficient your system will be.
I am currently investigating the same thing with regards to a pneumatic press where I don't want the compressor running 24/7 and one of the things I am encountering in the literature is a warning not to cycle a pump too often as it may damage the pump, for the vacuum system this means that a reservoir is not just a handy thing but more of a necessity. Actually, you would want a higher vacuum reservoir and vacume regulator to bleed a lower vacuum into the bag, ideally.. For my compressor press I have ordered a FESTO PEN M5 regulator, it handles vacuum as well as pressure, I hope I can figure out how to use it now...
:)
Edit: Great link on the vacum regulator mod from dream models!! That is toooo cooool! Wouter, I am thinking this may be your best option!
edit edit:
looks like this part from VW bug is still current: