Why are there two air gauges on a typical air compressor? A visitor that is new to air compressors sent in the question.
If you have used air compressors before, then you know why two air gauges on an air compressor is the norm. But what if you haven’t?
Tank Air Gauge
The typical air compressor has a tank into which the compressor pump pumps air to pressurize it. This tank typically has a gauge to display the pressure in the tank.
It is the tank pressure that the compressor pressure switch monitors as well, so it knows when to start or stop the air compressor motor, based on the pressure in the tank.
As the compressed air user, you need to know the pressure in the tank too, both to be sure that the air compressor is shutting off at the correct cut out pressure, and to know how much air you have available to you to work your air tools.
So, one of the two gauges on the air compressor is to display the tank air pressure.
The tank pressure gauge needle will display a lower pressure as the compressed air is being consumed, and the tank pressure displayed by the tank air gauge will increase fairly rapidly when the compressor motor cuts in to generate more compressed air.
Regulator Air Gauge
The other gauge on a typical air compressor is the regulator gauge. In the image below you see the regulator gauge extending towards you from the regulator body.
The regulator pressure gauge displays the pressure setting of that air regulator. This pressure setting is the air pressure which the user wants to send down the air line to the air tool.
Rule of thumb? Set the regulator pressure at the lowest PSI setting at which the air tool will run properly. This helps reduce air compressor cycling frequency (energy saver).
The regulator air gauge pressure display does not move a great deal (it typically bounces about 10 PSI as the air to the tool is turned on and off) unless the air consumed by the air tool is greater than the compressed air the compressor can generate. In this case the regulator gauge will display a steadily decreasing pressure.
Monitoring both gauges is useful for spotting irregularities when you are using your air compressor.
I have mixed feelings about your answer. Before this evening I had no idea of the purpose of the second gauge (the air pressure which the user wants to send down the air line to the air tool).
Decades ago I was a certified scuba diver but that wasn’t sufficient to explain why there are two gauges side by each.
I have used air compressors for decades though not a whole lot. Just for tire inflation, dust blowing etc but not for tools. I have fiddle-farted with the ‘second’ gauge with no discernible effect in practical usage.
I felt disrespected by your comment: If you have used air compressors before, then you know why two air gauges on an air compressor is the norm.
I watched several other videos, ALL of which TOTALLY IGNORED the ‘second gauge’!!!
Thanks to you I now have an idea of the ‘second gauge’s’ purpose. But nowhere have you indicated what its setting(s) should be and if there are reasons for different settings.
Howdy. No disrespect intended. The settings for the second gauge are actually covered on the regulator’s pages on this site. Simply, you set the pressure of the regulator at the lowest possible setting that allows the air tool to run and do the work it is intended to do properly. This will extend the life of the air in the tank, reduce the cycle frequency of the compressor, and save energy costs. Hope this helps.