Gas Mixer

The gas mixer has two inputs (Input and Input2), one output and a shared port for power and data. Setting (0 to 100, factory value 50) is the share of Input in percent; Input2 supplies the rest. At 100 only Input passes, at 0 only Input2. The connection diagram shows which port is which; when you look at the mixer in game, it names both shares.

It works in moles, not by pressure: each tick it takes from each input as much as that input's share of 200 kPa in 10 litres amounts to at the temperature of that input. The input pressure does not change the ratio – you do not need pressure regulators in front for that. Temperature does: if both inputs are equally warm, Setting is exactly the mole fraction and therefore the share of the output pressure. An example: Setting 22, oxygen at 20 °C (293.15 K), nitrogen at 0 °C (273.15 K). That gives (22 / 293.15) / (22 / 293.15 + 78 / 273.15) ≈ 20.8 % oxygen, because the colder input delivers more moles per litre.

Two quirks from the game code:

• If one input runs dry, the mixer stops (except at 0 or 100). It never produces a wrong mix because of that.
• It does not regulate the output pressure and keeps pushing even against higher pressure, at 20 °C at least about 0.82 mol per tick. Switch it off with IC10 as soon as a Pipe Analyzer at the output reports the target pressure.

You set Setting on the device in steps of ten, holding the key for small increments in steps of one. If you hold a labeller that is switched on, you type the value in directly. All three pipes must be connected, otherwise it reports Error. There are also On and Lock; readable are Maximum, Ratio, Power and RequiredPower; base draw is 100 W. More in Gases and mixtures: breathing air, gas mixer, partial pressure.