If a vacuum pump “pulls” 10mmHg, what is the atmospheric pressure inside the vacuum chamber?
To start, I’m a professional biologist, this is not homework. I am trying to figure out what kind of vacuum pump would work for a freeze dryer.
Most of the vacuum pumps that I’m seeing are listed with a “pulls XXmmHg” rating. I can’t imagine that this means that it is electronically set to create a vacuum that is at XXmmHg, but rather by some calculation would let me calculate, based on my current atmospheric pressure, what the pressure inside the vacuum chamber will be if I hook up this pump to a chamber.
Standard atmospheric pressure is defined as 100 kPa or 750 mmHg.
Example: if the pump pulls 10 mmHG, then remaining pressure is 750 – 10 = 740 mmHG = 98.66 kPa = 0.974 Atm
How the Nash Vectra SX vacuum pump works (long version)
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