My Paasche D500 compressor arrived today. Airbrush not delivered yet. The compressor has a pressure regulator and moisture trap installed. No tank. Do these compressors run all the time they are plugged in? Or do they shut off when they reach pressure? If they run constantly, do they just divert the extra air pressure if I am spraying at 30 pounds? I have used canned air [Propel] in the past, so this is new to me.
I'm NOT familiar with that particular compressor, but they come in mainly three types.
1) Run ALL the time, controlled by a manual switch. Usually these will overheat after a while if allowed to run against a 'stall' condition (no air flow).
2) Run ALL the time, with air pressure controlled by a 'bleeder' valve (internal or external), really just a controlled 'leak' that lets some air flow all the time. The bigger the leak the lower the pressure. Note that this can control the pressure, but NOT 'regulate' it. Also helps reduce compressor overheating by allowing some air to pass all the time.
3) Compressor controlled by a presure switch, and turns itself on and off as needed. Works best with a pressure storage tank.
All compressors will work best with a small 'surge' tank in the line somewhere. This evens out the compressor's air pulsations. some compressors, including some Paasches, have a small integral surge tank in the compressor head casting.
All air compressors generate heat, both in the compressor and in the motor. Generally, they should not get so hot that you can't briefly touch them, but they will get more than warm.