Gentlemen, I know many of you have knowledge beyond the main ideas of this forum so I'm asking a technical question which might be more suitable for some electricians/HVAC forum but nevertheless here it is:
Many years ago I built a DIY system for my modelling/painting needs. Using a Badger compressor and twin-tanks from a Campbell-Hausfeld compressor (was on sell at "Canadian tire" for 20$, compressor included), I managed to combine them in a decent system.
With some add-ons I can use the system for up to 3 airbrushes simultaneously. On the last photo you will see a plastic container with 2 electr. connectors - at that time the pressure-switch has not been added yet (the compressor didn't have a pressure-switch originally). With a pressure-switch set to 35 PSI the compressor works just fine. The problem is that this is a one-way switch, from the so called NC (normally closed) type. It turns the compressor off when the pressure in the tanks reaches 35PSI and turns it on when the pressure drops below 35PSI. Yes, not bad. But.....
The problem is that when I'm using 1 airbrush only, the consumed air is not too much and the compressor turns on and off every 5-6 seconds. This of course will shorten its life immensely. Better not having a pressure switch at all.
There are switches with 2 settings (industrial compressors have them) and I have one set to 70/100PSI: starts at 70PSI and stops at 100PSI.. There is no chance that my small compressor will reach these numbers (it goes up to ca. 40PSI). Unfortunately I couldn't find such "double" switch to set for lower pressure like 25/35PSI or sim.
There are switches, called NO (normally open) which can turn on your compressor when the pressure drops. But how to connect 2 pressure-switches in one system.
With some search I found that this is possible only when using a modular contactor. Something like this. The latter has to be NO (normally open) to work with the 2 pressure-switches for pressure control.
This is the scheme for the electrical connections (Coil K is the contactor):
For the air I just have to split the hose from the tank in two separate lines to the 2 switches - it's the same air and pressure for both.
Does anybody has any knowledge with similar systems?
Can I use the 2 pressure-switches connected in series or parallel (whatever) and forget about that contactor?
Thanks in advance!
Cheers!
P.S. Sept.29, 2025
Just to finalize the tread: I got a good advice a couple of days ago that pressure-switches for water pumps are set for lower pressures and can be used with air systems as well. Found a double pressure-switch 40/20PSI on Amazon.ca for less than the price for 2 separate switches, not to speak of a relay(contactor) and/or other electronic elements.
I did speak with a professional and have been advised that the system shown in the scheme above DOES NOT WORK - there is no way to stop the 40PSI switch not to turn on below 40PSI.
Today I set up my old-new compressor and happily used it in an auto-mode (off @ 40 PSI, on @ 20 PSI).
Cheers!
Many years ago I built a DIY system for my modelling/painting needs. Using a Badger compressor and twin-tanks from a Campbell-Hausfeld compressor (was on sell at "Canadian tire" for 20$, compressor included), I managed to combine them in a decent system.
With some add-ons I can use the system for up to 3 airbrushes simultaneously. On the last photo you will see a plastic container with 2 electr. connectors - at that time the pressure-switch has not been added yet (the compressor didn't have a pressure-switch originally). With a pressure-switch set to 35 PSI the compressor works just fine. The problem is that this is a one-way switch, from the so called NC (normally closed) type. It turns the compressor off when the pressure in the tanks reaches 35PSI and turns it on when the pressure drops below 35PSI. Yes, not bad. But.....
The problem is that when I'm using 1 airbrush only, the consumed air is not too much and the compressor turns on and off every 5-6 seconds. This of course will shorten its life immensely. Better not having a pressure switch at all.
There are switches with 2 settings (industrial compressors have them) and I have one set to 70/100PSI: starts at 70PSI and stops at 100PSI.. There is no chance that my small compressor will reach these numbers (it goes up to ca. 40PSI). Unfortunately I couldn't find such "double" switch to set for lower pressure like 25/35PSI or sim.
There are switches, called NO (normally open) which can turn on your compressor when the pressure drops. But how to connect 2 pressure-switches in one system.
With some search I found that this is possible only when using a modular contactor. Something like this. The latter has to be NO (normally open) to work with the 2 pressure-switches for pressure control.
This is the scheme for the electrical connections (Coil K is the contactor):
For the air I just have to split the hose from the tank in two separate lines to the 2 switches - it's the same air and pressure for both.
Does anybody has any knowledge with similar systems?
Can I use the 2 pressure-switches connected in series or parallel (whatever) and forget about that contactor?
Thanks in advance!
Cheers!
P.S. Sept.29, 2025
Just to finalize the tread: I got a good advice a couple of days ago that pressure-switches for water pumps are set for lower pressures and can be used with air systems as well. Found a double pressure-switch 40/20PSI on Amazon.ca for less than the price for 2 separate switches, not to speak of a relay(contactor) and/or other electronic elements.
I did speak with a professional and have been advised that the system shown in the scheme above DOES NOT WORK - there is no way to stop the 40PSI switch not to turn on below 40PSI.
Today I set up my old-new compressor and happily used it in an auto-mode (off @ 40 PSI, on @ 20 PSI).
Cheers!
Last edited:
As an Amazon Associate we earn from qualifying purchases.
