Honeywell ST 3000 User Manual page 89

6.4 Selecting Output Form,
Keystroke summary
About square root
output
6/05 ST 3000 Release 300 and SFC Model STS103 User's Manual
Figure 27 shows keystroke summary for selecting output conformity for
quick reference.
Figure 27 Keystroke Summary for Selecting Output Conformity.
For differential pressure transmitters measuring the pressure drop across
a primary element, the flow rate is directly proportional to the square
root of the differential or pressure drop. The ST 3000 transmitter's
output is automatically converted to equal percent of flow when its
output conformity is configured as square root.
You can use these formulas to manually calculate the percent of flow for
comparison purposes.
∆P
Span • 100 = % P
∆P
Where,
Span = Transmitter's measurement span (URV – LRV)
% P
%P
Therefore, 100 • 100 = % Flow
And, you can use the following formula to determine the corresponding
current output in milliamperes direct current.
(% Flow • 16) + 4 = mA dc Output
Continued
B
CONF
NON-VOL
ENTER
(Yes)
DE CONF
I
MENU
ITEM
NON-VOL
ENTER
(Yes)
NON-VOL
ENTER
(Yes)
22507
= Differential pressure input in engineering units
= Pressure input in percent of span
Continued on next page
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