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this table.
11. Press the PRGM key.
Top line reads “USER UNIT
NAME”.
12. Follow steps 6-8
above to enter “FT H2O”.
Bottom line reads “FT H2O”.
Last letter “O” is blinking.
13. Press the PRGM key.
Top line reads “PROGRAM
MODE”.
Bottom line reads “UNITS
SELECT”.
14. Press the arrow
key.
Bottom line reads “EXIT”.
15. Press the PRGM key.
Manometer returns to Measure
Mode. Units Display shows “FT
H2O”.
Note 1: If at steps 4 or 10 the “VALUE=” is the desired value,
press the or arrow key. This will toggle the bottom line from
the default “CHANGE?: YES” to “CHANGE?: NO”. Step 5
would then jump to step 10. Step 11 would then jump to step 13.
Flow Unit Select
Smart Manometers that use differential pressure sensors can be
programmed to read out flow measurement units such as CFM or
L/min. The primary element must be a differential pressure -
square root type device such as a pitot tube, orifice plate or venturi.
The flow constant and flow units description are programmed into
the manometer using the same keystrokes used in the User Unit
Select programming. At step 3 choose “FLOW UNIT SELECT”
instead of “USER UNIT SELECT”.
Calculate the Flow constant from the following equation:
F
c
= Q ÷ DP
½
where: F
c
= Flow constant
Q = Flow rate
(from flow element calculation sheet)
DP = Differential pressure corresponding to Q
Example: If the DP is 25 units when the flow rate is 10,000 units,
then the Flow constant is 2,000.
Damp Rate Select
Adjustable exponential type damping is available to steady the
display when measuring pulsating pressure or flow. The Smart
Manometer has a range of damping rates; 0.1, 0.2, 0.5, 1, 2, 5, 10,
or 25 seconds. Exponential damping shows approximately 70% of
a step change in pressure upon the next display update. When set