Siemens SITRANS FUH1010 Product Instruction Manual page 86

Setting the Pressure Slope
The flow meter measures and reports the flowing liquid's sonic velocity (Vs) and its related
pressure (P). Since a pressure change will affect the sonic velocity of the liquid, a method to
balance the measured sonic velocity to a fixed reference temperature (15.6ºC/60ºF) default)
is provided. The Pressure Slope Factor default is 0.030 (m/s per PSI). This pressure slope
factor helps maintain an accurate liquid identification as the LiquIdent factor and liquid
temperature vary.
The flow meter has the ability to accept a 4-20 mA input for pressure. If used, the flow meter
will process pressure data based on the analog input. This is recommended for pipelines that
have wide pressure variances.
To calculate a liquid's Pressure Slope Factor:
1. Establish the maximum (Pmax) and minimum (Pmin) pressures for all liquids within the
2. Use the following formula to calculate the Pressure Slope Factors with the Liquid Class:
3. Calculate the average of all the Pressure Slope Factors within the Liquid Class.
To enter the Pressure Slope Factor
1. From the [Liquid Table] menu cell, press <Up/Down> Arrow> to scroll down to [Pressure
2. Press <Right Arrow> to enable numeric entry.
3. Use the keypad numeric keys to enter the desired Pressure Slope Factor.
4. To enter the Pressure Slope Factor press <ENTER>.
5. This moves the highlight down to [Base Temperature].
Setting the Base Reference Temperature
The flow meter uses a reference Base Temperature of 15.6ºC (60ºF) for the LiquIdent
calculation and Standard Volume compensation. Any temperature can be entered and used
as the reference Base Temperature (e.g., 20ºC/68ºF).
To enter the Base temperature:
1. From the [Liquid Table] menu cell, press <Up/Down Arrow> to scroll down to [Base
2. Press <Right> to enable numeric entry.
3. Use the keypad numeric keys to enter the desired Base Temperature.
4. To enter the Base Temperature press <ENTER>.
FUH1010 IP65 NEMA 4X Precision Volume
Operating Instructions, 01/2013, A5E32122003-AA
Liquid Class. For each liquid, note the measured sonic velocity at Pmax and the sonic
velocity at Pmin (in-meters-per-second).
Slope].
Temperature].
Functions
7.1 Setting Liquid Parameters
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