Wow, lotsa jabber. Maybe I should have plowed through it all,,, oh well.

On your actual posed question:

You should use what we always called a "bulkhead fitting". You want to pass those insulated conductors through that wall as simple insulated conductors, and do your connectors separately. If you have signals requiring shielding, you are typically better off to separate them, possibly to a separate fitting, to keep signals clean.

Essentially, such fittings, typically threaded, produce a very tight seal intended to withstand substantial pressure differentials continuously, and chemicals and gasses not known to have deleterious effects on your chosen conductor insulation jackets. They are available with conductors in place and potted, or as ready to assemble pieces which you pass your own conductors through.

Sorry, but could you do a quick ELI5 (explain like im 5) on the function of said fitting? Do I simply tighten it onto the chamber and pass the entire bunch of wires through it? How exactly does it ensure no leakage through the feedthrough?

Anyway if I'm not too clear about my setup, here is a (bad) drawing of it: https://imgur.com/LtbLbCC

What kind of signals are on those 13 wires? Some may have trouble going through that connector.

Things to consider minimum and maximum levels are:
Voltages
Currents
Frequencies/rise time/fall time
Impedance

I don't exactly know what functions each of the 13 wires provide... All I know is they help me power the server on when I press that button... Haha. Sorry about that. Is there anyway I can find out? (Considering these servers and their components are typically proprietary)

The KJL website states a maximum of 500V and 5A is acceptable through each pin, so it should not be a problem...?

**Also for the guys worrying about cooling - thermal management is the main aim of this experiment, so we do have our cooling methods within the chamber for the server. Nothing's gonna overheat (hopefully)!**

 

What you are looking for are commonly called Vacuum/Pressure Feedthroughs, NPT Fittings in the US only because of the NPT (National Pipe Thread) designation, the link is an example of what they look like.Another popular term is through the bulkhead vacuum fittings. They are a fitting with wires as pictured in the link, and potted. A hole is drilled and tapped in the vessel and a good thread sealant applied like teflon tape or blue goo . These are just a few examples.

Ron

 

@toiletmirror,
The imp75 is a temperature sensor with I2C bus, the leds are for feedback. The only thing turning on your server you need to worry about is that switch. With the server off, use a multimeter to measure the voltage from pin to pin of that switch. Find two pins where if you touch the multimeter to them you record a voltage. Then use a wire to short out those connectors. Your server should turn on. When it does, solder two wires -- one to each pin, and run those two wires out of the vacuum chamber.
Cheap, easy, fast.
If you have a mechanical feed-through, you could just use that to push the button and be done even faster.

To your other question -- that plug that you're looking to buy might need to be welded to a flange -- and unless you've got experience welding TIG stainless, leave it to the machine shop.
Mark

 

It depends on the pressure level you are attempting to achieve.
What level vacuum do you need?

You have two problems. Anything you place inside the vacuum chamber could keep on out-gassing and prevent you from reaching the desired pressure.

Secondly, any feed-through connector has to be designed for that level of vacuum.
There are special epoxy glues that are designed for high vacuum applications. We seal all our connectors with this epoxy.

There used to be feed through capacitors made of glass or ceramic - not exactly deigned for this purpose, but there are various adhesives/sealants that would fix the unlikely event of a leak.

AFAICR: 1nF was a popular value, but it should be possible to find lower. Its likely to be inherent with high voltage types.

 

Do your googling. I used Woodhead branded fittings, which I see are now a division of Molex, and those were either assemblies with leads of whichever size and length I ordered, or a fitting very similar to a compression style cord grip.

You could also actually use one of those, but you build the "packing", by wrapping, starting with one insulated conductor and adding the rest as you wrap, using 3M 130C or equivalent tape. For substantial pressure differentials you'll need UHMW type packing washers drilled to match your rubber packing.

Depending on the thickness and composition of the penetrated wall, you'll either drill and tap it, or use a threaded stem or nipple, O-rings and nuts.

I'm not up to a couple thousand more words, so go googling for a few pics. This is stuff industrial electricians and I&C guys do all day long, so it shouldn't be hard to find.

 

I found a few through bulkhead connectors I had for pressure/vacuum applications. The ones I have were made by Pave Technology Company and while I don't expect anyone to call them tomorrow the link gives some good illustrations. If you scroll down the linked page you can see some dimensions and designs.

Ron

 

I found a few through bulkhead connectors..... made by Pave Technology Company and while I don't expect anyone to call them tomorrow.....
Ron

Yeah, I've used those too, they're very high quality as I recall.