To maximize the life of my homefill, I'd like to manifold three tanks together, and only run them up to 1000 psi. I modified my whip with a high pressure T and added an up to 4000 psi pressure gauge to see where I'm currently sitting, and then just manually turn them off at around 1000 psi.

So here is what I would like to do. I would like to either alter the pressure cutoff switch in the unit to have it shut off at a lower pressure, or I would like to install a pressure cutoff switch as part of either my manifold or whip, so that when it reaches 1000 PSI, it just kills the power. The problem with that second one would be that the machines alarm goes off anytime it loses power other than having the face switch turned off, but I could deal with that part, as I guess it would serve as an audible note that I'm done filling for the day.

I've done some searching online and on here, but am unable to find anyone else whose done this, and most of the pressure cut off switches I can find are not rated up to the pressure I need. Does anyone have any experience with this, or could point me in the right direction for where to look for switches that are rated for oxygen, and are either set to shut off at 1000 psi, or has a variable setting to I can dial in the pressure I want?

Thoughts?