I figured it out.
Thank you everyone for sharing this information!
How much is the sensor?
Sorry. One more question.
This doesnt seem right. This is with alcatel 2021i. Shouldnt it be reading a bit higher?
Units is torr, and gas is nitrogen(drop down boxes)…is that what you want?
From what I’ve read people usually use micron.
is 1 torr = 1000 microns?
1 Like
Pretty much.
Did you get a reading with no vacuum?
How is the gauge connected to the pump?
What kind of reading were you expecting?
2 Likes
I did get a reading with no vac. On the table open to the air it was 718.
When I first started the pump it was .25 tor. got all the way up to 1.5 tor when the pump warmed up.
I connected the gauge to a KF16 to a KF25 adapter directly to the pump.
I was expecting something much much lower. I was expecting at least 100micron. is that not a proper expectation?
I might have lost the ebay lottery on the 2021i’s.
i already tried flushing it with kerosene/oil, no go. maybe i dont have it flushed out enough. ill reread the 2021i thread. maybe i need to figure out the ballast screw and run it with that open for a bit.
1 Like
Could be the pump, could be the gauge.
Should have been around 760 with no vacuum.
The calibration section in the manual says it could read as high as 900 when exposed to atmospheric air because it is factory calibrated for nitrogen.
But the low end and high end calibration are done differently. And fixing the high end reading won’t fix your issue.
2 Likes
Thanks man, I appreciate the help. Just trying to get it all figured out.
I’ll tear my pump apart this weekend and scrub it out then try and vac down the sensor and zero it.
Hey you can calibrate your atmospheric pressure by getting a barometric reading where your lab is. To be really precise it changes with the weather so you can monitor it to see if your gauges calibration is on. I have an app on my phone. It comes in handy. It will be in mbar
3 Likes
so grab an app that will give me the atmospheres pressure in mbar, switch my serial command to display the sensor in mbar and see if they match up?
i believe i read a way to zero the sensor to atmosphere in the manual. Ill and to reread that section now.
Thanks for the pointers guys, it helps me out a bunch.
In the manual there is a calibration code you can enter. In scriptcommander you type that into the main window and then hit the send button. Both my vacuums pull to around where they are supposed to (depending on how they are hookedup and such).
1 Like
This is a trick of the trade tread tip👍
Would you please write the app s name and a detailed work out in the trick of the trades tread ? Will help out plenty of folks !
just had a chance to check out what @The_Lone_Stiller suggested.
wanted to get your opinion.
my sensor is reading 990 mbar. my samsung galaxy sitting next to it is reading 997 mbar.
for an amateur like me, is that close enough? which would you feel is more accurate?
1 Like
Ok I think I got it all.
One last question. I had it down to .01 torr. Did an oil swap and it went from .01 to 0. Is zero as low as I can get? what would that be considered in microns?
1 Like
I have it set to only display 2 digits I think and if you look at the exact response it is 2.91 E -3. I will have to do some editing down there! I can’t recall exactly but I think I used a built in rounding function. I can also make it ask for a 4 digit response as well. When I wrote it I was using a chemical diaphragm pump but I’ve been also using a rotary vane now recently and have been meaning to adjust the digits.
3 Likes
so .00291 torr
2.91 micron
2 Likes
Ha. Thanks. I actually was just figuring that in my own as I read your response. I’m slowly getting it now…I think.
2 Likes
I mean…
Unpopular opinion here…
As long as you’re getting a good end product with a low mantle temp. Your vacuum gauge doesn’t matter so much for absolute accuracy, but more just for accuracy to itself.
If you’ve done a couple runs, as long as it’s reading similar numbers to the previous runs, it’s probably nbd. +/-10% isn’t going to give you any more useful info. A vacuum leak will bump your results considerably more that +/-10%. A gauge is really most useful to find leaks, beyond that the data doesn’t really impact much. Your mantle temp can tell you just as useful info.
1 Like
Agree the vacuum gauge is there to see if system is sealed and ready to go
If there are discrepancies it doesn t really mater
For a strip run but for fraqtioning of cannabinoids like CBN it is very useful
If a logbook has been kept to figure out where your best cut is for tails
On well cleaned post distillation sop
Crude cannabinoids evaporate fairly linear
3 Likes