new automated vacuum system

[nicolas leboucher]

Hello,

I m on the way to complete my multipurpose automated vacuum system from the parts of an old project.
My main goal is still to embody the work done by chris bradley on the "epicyclotron", well described in this forum.
As i also plan to conduct further particles physics experiments, I realize that i need first of all to build a flexible vacuum and experiment chamber system, and later HV PSU.

As i also need to carry it with my car for holidays between my flat in Paris, where i just have enough space to work on electronic projects, and my house in south-west of france (where is my main workshop), i try to build it as compact as possible, with an alu shape with wheels. The primary mechanical pump is fitted in an other trolley ( not on the picture), and i plan to build another one for HV PSU and control pc.
Based upon a diffusion pump which require many care and a precise operating process, and as I have good knowledge on DAQ hardware and software, i ve decided to automate the system with I/O usb card (labjack U12) and a Labview application. For safety purpose, i build a manual control panel in case of computer failure. Just for fun and as i m really a particle accelerators enthusiast, the labview software also includes an EPICS server so that you can check or control the system with a ethernet connection.

a screenshot of the LABVIEW control windows, which also show the main parts:

The main parts:

diffusion pump Edwards Diffstack 63/150 water cooled
mechanical pump ADIXEN pascal 2010SD ( note in the same rack)
3 inficon pneumatic vacuum angle valves solenoid actuated ( need a CO2 bottle from aquarium )
2 edwards vacuum valves solenoid actuated
1 inficon pilot plus vacuum gauge ( not on this rack, directly connected to the inlet of the primary pump - pictures to come)
1 convectron gauge ( granville philips)
2 ion gauges ( granville philips)
many flanges KF standard
various PSU to provide 110 vac, 24 vdc, 12 vdc

the vacuum chamber will be implemented within the next weeks, waiting for parts to achieve it.
During the first tests last mouth, i was able to reach a 10E-5 Torr vacuum.

more to come.

[Philipp W]

Hi!

I like your setup - compact and yet flexible!

How exactly does your water cooling loop for the Diffstak look like? I'm especially interested in your radiator and its size. What coolant temperatures can you achieve in steady state?

Thanks a lot!
Philipp

[nicolas leboucher]

hello philipp

the diffstak 63/150 requires a minimum flow of 42 l/h for cooling water. I ve built the water cooling system from used automotive spare parts. It is not yet mounted in the rack, but i ve tested it in july.

- a facet pump, normally used for fuel injection - pressure: 0,5 bars, flow: 150 l/h, 12 VDC - very interesting for this purpose: low pressure, high flow
- a heater from car air conditioning : 195 mm x 165 mm x42 mm
- a 220 vac fan on the heater
- an expansion tank from a motorcycle
- about 1 liter of coolant for cars
- all the hoses also coming from my automotive spare parts : 10 mm inside diameter standard cooling hose

the diffstak works during several hours without any problem, but i ve planned to replace the security thermocontacts with temperature sensors to have a more accurate control system

I will post some pictures as soon as possible

[Philipp W]

Hi,

thanks for the information! Interestingly, I've also used the same approach using automotive heat exchangers. Not tested yet, however -- I'm still missing some parts.

Looking forward to your pictures!

Philipp