yobbo II - 22-8-2022 at 05:42
Hello,
I obtained the following (thanks to Mush).
It shows a simple vacuum controller that will regulate from 1 to 50cm of water.
Would this do for vacuum distillations.
Yob
Attachment: 10.1063_1.1137334.pdf (387kB)
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Rainwater - 22-8-2022 at 17:00
it looks like that would regulate a positive(relative) pressure. With the water tube pushing in the membrane, once the pressure exceeds the force
required to open the membrane, excess pressure would be vented. Adjusting the height of the "leveling bulb" would adjust the pressure required to open
the membrane(valve). So the lower the bulb, the lower the pressure as read at the point labeled manometer. The higher the bulb, the higher the
pressure.
Its actually a genius design in its simplicity.
As for vacuum applications, if it did work in that configuration, by replacing the air pump with a vacuum source, it seems that it would bleed air
into the system, but the "level bulb" would operate in reverse. With the bulb higher, the vacuum would be stronger.
One design consideration would be the membrane sucking into the opening toward the vacuum, which would lock the regulator. A stiffer material may be
needed.
As long as the leveling bulb was applying a downward force on the membrane it could work.
Good luck. And please let us know what you find out
If you want a black box fix i would recommend this.
https://www.digikey.com/en/products/detail/panasonic-industr...
We use these at various factories, mainly to alarm when a suction cup fails or to cycle the house vacuum pump on/off to maintain a large reservoir.
Their very accurate when the temperature is stable. -100~100kPa, and have a programmable npn which is capable of switching an ssr or plc point.
Datasheet
Attachment: dp-0_e_cata.pdf (2.1MB)
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