For model 7 differential pressure gauges, the static pressure is the same as the full scale value over 270 degrees of rotation. With an expected differential pressure of 15 psi (1 bar) at a static pressure of 145 psi (10 bar), the two hands would only be separated from each other at a distance of approximately 27 degrees. As a result of this, to ensure that readability is still acceptable, the differential pressure should not drop below 1/6 of full scale (approx. 45 degrees).