When auto flow is turned off and the vent is in conventional peak flow, the set I time is set and the peak flow is set, which supercedes the other? How does inspP work in this setting?
The two are independant to a point. The Peakflow determines the minimum IT to achieve the set VT, if your set IT is longer than the minimum It then you have created a pause. The Drager doesn't have a pause setting, but you can still create one using this method. I teach my students to set their IT for the desired flow rate then spin the IT down untill it states that they must adjust flow to go any shorter and then confirm it there.
From my memory of the Evita (pre XL).
With Autoflow off you have two choice.
Use traditional square wave flow pattern.
Turn on Pmax and then the Pmax setting becomes a pressure setting whereby the flow "bonks" into that pressure and then ramps down.
You set an Insp time. Obviously part of that time has to be an insp pause or otherwise you are cutting it too close.
So in Pmax with a VT 600 and a flow rate 100L/M and a Pmax setting of 28....
Flow charges out the gate square wave at 100 L/M. As soon as it bonks into 28 pressure it ramps down and "hugs" that pressure in a decelerating wave. As soon as the VT is delivered it is then an insp pause. If the combination of compliance/resistance, VT, flow rate, insp time, set flow, doesn't allow enough fudge for the VT to be delivered then there is an alarm.
This is basically the same as the Eagle Univent when the Plateaue Pressure is activated (dumb name--people think it's to check plateau pressure).