This is what it says in Newtis for normal pressures:

Connect service station to car and open both valves on the charging hoses. Adjust A/C system at control panel as described for A/C efficiency measurement.
Note:
The following values apply as normal pressure ranges for ambient temperatures between + 20°C and + 40°C:
Inlet pressure: 1.0 - 2.2 bar
Outlet pressure: 12 - 22 bar

2.2 bar is just under 32 psi. 40C is 104F.

I don't understand why that differs so widely from system pressure chart.