Crystal XP2i-DP Digital Differential Pressure Gauge - Manual (Page 9)

Applications  7
XP2i-DP Operation Manual
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contInuous VacuuM
The unique design of the differential pressure sensor integrated into the XP2i-DP allows for long term vacuum use without fear of permanent damage to the
sensing chip or package. When measuring high vacuum gauge pressures continuously it is recommended to connect the static line pressure to the right (–)
port marked "Vacuum this side". To achieve gauge measurements, the left (+) port is left vented to atmospheric pressure.
Vent Vacuum
Note: When connected in this orientation, the XP2i-DP display will invert the sign on the gauge display. For example, a pressure of -12 psi on the negative
port will display +12 psi. To invert the sign to read -12 psi, use ConfigXP Software (V 2.4 or later).
Select Enable Vacuum Mode and update the gauge to properly display a negative pressure value.
!
WARNING: pressure applied to the + sensor port must be greater than or equal to the pressure applied to the – sensor port.
The vacuum accuracy of the gauge will be calculated the same as a differential measurement. Therefore, the 12 psi measurement, when compared to a 100
psi full scale gauge used, will require the 0 to 20% of Full Scale, ± 0.02 % of Full Scale accuracy statement.
The vacuum accuracy for this test condition is as follows:
± (0.02% x 100 psi) = ± 0.02 psi.
When using a 15 psi full scale gauge, this will require the 20 to 100% of Full Scale, ± (0.1% of Reading) accuracy statement.
± (0.1% x 12 psi) = ± 0.012 psi.