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ADDENDUM FOR DIFFERENTIAL PRESSURE TRANSMITTERS:
SELECTABLE OUTPUT FUNCTIONS
GENERAL DESCRIPTION
The 600T Series Differential Pressure Transmitter provides a selection of output functions, as follows:
Linear
for differential pressure or level measurements
Sq. Root (x)
for flow measurements using restriction type primary element, like orifice plate,
integral orifice, Venturi or Dall tube and similar.
Sq. Root (x
3
)
for open channel flow measurements using rectangular or trapezoidal weir
Sq. Root (x
5
)
for open channel flow measurements using V-notch (triangular) weir.
Polynomial
for input linearization using a 5th-order polynomial function
for input linearization using 2 polynomial functions of 2nd order
Costant current
for loop or associated equipment test.
where |x| and output are in the range 0 to 1 (0% to 100%).
Figure 1 shows the Input/output relationships with the different Square Root Options applied.
These output functions can be activated using a Configuration Tool like the Hand Held Communicator, a HART Universal
Communicator or a Personal Computer, carrying the Smart Configuration Program, connected to the transmitter via a Bell 202
modem (see the relevant Operating Instructions). In the Analog version the Sq. Root (x) can be selected through the use of a
hardware link (see the ADDENDUM use of Hardware links on the secondary electronics).
The output of the transmitter is actually the analog signal 4 to 20 mA and the digital signal read in engineering units on the integral
display.
0
0.1
0.3
0.5
0.7
0.9
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0.2
0.4
0.6
0.8
1
Differential Pressure %/100
Flow %/100
Sq.Root x
Sq.Root x^3
Sq.Root x^5
Fig. 1
