Xylem XL Series H-522 - Plus - Manual (Page 91)

XL™ Series
Built In Stage / Remote Stage Setup 10-3
PC Interface View Built In Display Screen
U - Units: Feet Units [Feet ]
This option screen allows the user to choose the units for reporting the calculated stage value.
The H-350XL™ actually measures the pressure (PSI) on the orifice line, but the default stage
reading is reported in feet. The conversion from PSI to feet is PSI * 2.3067 at ideal conditions.
The table below gives a few standard conversions for ideal conditions.
Multiply PSI by (Slope Value) To Obtain
1.0 PSI
2.3067 (This is the default) Feet
0.70308 Meters
27.6804 Inches
User Entered Value Desired User Units
Valid options for the units are Feet, Meters, Inches, or UserDef. If “UserDef” is selected, a
prompt is displayed for the user to enter in a value for the slope. For example, if a user wants to
see how close the water is to the top of the river bank in feet, meaning the value should get
smaller as the water level rises towards the bank. The user selects “User Def,” and enters a
slope of -2.3067. Using a negative value will cause the H-350XL™ to display decreasing values
as the water level rises. The magnitude of 2.3067 is still valid to convert PSI to feet. This is done
using the standard editing methods to change the slope.
PC Interface View Built In Display Screen
A - Averaging Time: 001 Seconds Averaging Time [001]
This option screen allows the user to select the duration of the H-350XL™ pressure
measurement. The pressure used to calculate the stage is the average pressure over this averaging
time. This value can be set from 1 second up to 360 seconds (6 minutes). The default value is 1
second. If the water level to be measured is rough or unstable, a longer averaging time could be
used to give a more accurate reading. Some conditions may require an averaging time of 2 to 5
seconds, but others may need as long as 20 seconds. For applications dealing with tidal effect or
other wave action, an averaging time of a few minutes may be required.