Probe Software Users Forum
General EPMA => EPMA Laboratory Planning and Design => Topic started by: Probeman on October 01, 2014, 03:49:49 PM
-
Ok, I'll get things rolling as I have spent considerable time and effort thinking about optimizing laboratory performance and stability in the designing of our CAMCOR characterization labs in Huestis Hall. The entire facility consists of a single story underground with turf overhead and rock underneath. Now just with this type of siting, one can improve vibration, EMI and temperature control. For those interested in more details see this link here:
http://camcor.uoregon.edu/about/facility-tour
For those of you that have visited our facility you are aware that it is quite nice with impressive performance specs which I will insert as an attachments below for more information. For example, vibration levels 4 to 8 times better than NIST-A depending on frequency.
(https://probesoftware.com/smf/oldpics/i61.tinypic.com/2mph5kj.jpg)
This was taken while we were moving the instruments in:
(https://probesoftware.com/smf/oldpics/i58.tinypic.com/14ecehg.jpg)
A shot after the SX50 and Sx100 were moved in:
(https://probesoftware.com/smf/oldpics/i60.tinypic.com/i3dkjs.jpg)
-
The best way to determine temperature stability for your laboratory is to directly measure temperature using a digital recording thermometer. There are many models available and usually cost between $200 to $400. This is the one we use though it is a little more expensive:
http://www.dicksondata.com/products/FH625
Because most labs I've worked in have terrible temperature stability control (usually the A/C is insufficient in BTU rating), I implemented a drift correction for the unknown measurements that is automatically applied to all unknowns if they are between standardizations in real time.
Here's an example of several days of operation in our new lab which shows excellent intensity stability:
Drift array standard intensities (cps/30nA) (background corrected):
ELMXRY: na ka si ka k ka al ka mg ka ca ka ti ka mn ka fe ka p ka cr ka
MOTCRY: 1 TAP 2 LPET 2 LPET 4 TAP 1 TAP 5 LIF 3 LLIF 3 LLIF 5 LIF 4 TAP 3 LLIF
STDASS: 336 162 374 336 162 162 22 25 162 285 396
STDVIR: 0 0 0 0 0 0 0 0 0 0 0
2533.6 9875.5 6024.1 8171.4 2855.9 328.8 6415.5 14908.2 596.5 9707.0 5288.6
2522.5 9977.4 6006.2 8341.4 2841.3 338.5 6377.0 14945.2 596.2 9633.9 5166.0
2517.3 9989.2 6010.5 8218.5 2837.0 339.9 6428.2 14926.4 601.5 9695.2 5231.3
2504.6 10013.6 5999.0 8312.4 2850.8 337.9 6456.1 14052.2 606.4 9566.2 5212.1
2522.0 10026.2 5159.5 8303.9 2834.5 337.0 - - 599.4 - -
- 10011.7 - - 2820.3 333.8 - - 600.0 - -
- 9995.9 - - 2855.1 337.5 - - 600.3 - -
But even though the temperature control in our new lab is excellent, we still almost always measure standards before and after all unknown runs because in PFE it is just a couple of mouse clicks (assuming your standards are in the instrument along with your unknowns!), and then you know for certain that the instrument was stable during the entire measurement period.
And if it wasn't, the automatic drift correction in the software takes care of it for you anyway!
-
I took a few pictures showing a few of the features of our equipment gallery.
They are attached and are annotated so they should be self explanatory, but they include the pump vibration isolation, "slow opening" rough valves, P-10 low pressure alarm, diesel backup up UPS unit, and the Al shielded power panels...
The modeling of the EMI reduction from the Al shielding is posted here:
http://probesoftware.com/smf/index.php?topic=354.msg2066#msg2066
I should mention that the Aqua-Trap cold trap supplied by Cameca (made by Poly-Cold in California) is exceptionally robust. No problems and it maintains 100 degrees Kelvin all the time. I warm it up once a year to be safe.
The 6 mm (1/4") Al sheet EMI shielding extends all the around around and in back of the power panels between the power panels and the laboratory wall. This is documented here:
http://probesoftware.com/smf/index.php?topic=354.msg2066#msg2066
-
Attached (remember, you must be logged in as a member to see), are a number of building design and specification documents we utilized in our Lokey Lab building.
Please let me know if you need additional information or have any questions.
john
-
Attached (remember, you must be logged in as a member to see), are a number of building design and specification documents we utilized in our Lokey Lab building.
Please let me know if you need additional information or have any questions.
john
-
Attached (remember, you must be logged in as a member to see), are a number of building design and specification documents we utilized in our Lokey Lab building.
Please let me know if you need additional information or have any questions.
john
Thank you John!
Did I do it right? ;)
-
Attached (remember, you must be logged in as a member to see), are a number of building design and specification documents we utilized in our Lokey Lab building.
Please let me know if you need additional information or have any questions.
john
Thank you John!
Did I do it right? ;)
I'm sure. Did I?
-
Our "facility tour" page is finally back up in case anyone is interested.
http://camcor.uoregon.edu/facility-tour
From the main page there are other facility links as well:
http://camcor.uoregon.edu/
-
Does the back of your instrument look like this?
(https://probesoftware.com/smf/gallery/395_17_11_23_5_06_27.jpeg)
By the way, this is *not* an EPMA instrument! But if the back of your instrument has a mess of cables, perhaps you need these:
https://www.gear4music.com/us/en/G4M/5-Channel-Cable-Protector-Bridges-by-Gear4music-Pack-of-3/23HY
We used many of these in our facility and it really helps to prevent weird connectivity problems from technicians walking on various cables!
-
Does the back of your instrument look like this?
What a setup! I am amused by the size of that HV tank supply. It even has a pressure gauge (for oil)? What kind of instrument is it supplying?
I just want to point out (not for probe, as normally cabling is tided inside, and at least Cameca signal cables are shielded or/and differential) that sometimes tidying cables can increase cross-talk interference to not well shielded and not-differential signal cables. And it can happen that such a mess, as presented in the picture, just works, but after tiding it up the system starts to randomly malfunction.
-
Does the back of your instrument look like this?
What a setup! I am amused by the size of that HV tank supply. It even has a pressure gauge (for oil)? What kind of instrument is it supplying?
I just want to point out (not for probe, as normally cabling is tided inside, and at least Cameca signal cables are shielded or/and differential) that sometimes tidying cables can increase cross-talk interference to not well shielded and not-differential signal cables. And it can happen that such a mess, as presented in the picture, just works, but after tiding it up the system starts to randomly malfunction.
I suppose anything is possible, but we have found that the use of these cable bridges actually reduces cross talk. Why? Because the use of these cable trays spreads out the cables into separate channels so there is more spacing between cables.
The photo is the back of a customized Auger instrument from JEOL.