2020.07.24
•
REV. 2
• MASS FLOW METER OPERATING MANUAL
27
Defining STP/NTP Reference Values
Standardized flow rates are reported in “standard” or “normal” volumetric
flow units that reference a given temperature and pressure combination.
This reference is called an STP (standard temperature and pressure) or,
typically in Europe, an NTP (normal temperature and pressure).
Menu
→
Basic Config
→
STP/NTP
UP
DOWN SELECT
Stan T: 25.00 ¤C
>Stan P: 14.70 PSIA
Norm T: 0.00 ¤C
Norm P: 14.70 PSIA
Ref temp units
Ref pressure units
BACK
CHANGE
STP/NTP menu
UP
DOWN SELECT
DIGIT
Ref Temperature: ¤C
25.00000
^
BACK/
CANCEL CLEAR
SET
Selecting a standard
Stan T
: Standard Temperature
Stan P
: Standard Pressure
Norm T
: Normal Temperature
Norm P
: Normal Pressure
Ref temp units
changes the
temperature units used for
STP and NTP calculations.
Ref pressure units
changes
the pressure units used for
STP and NTP calculations
Using the
STP/NTP
menu, you can independently change the temperature
or pressure references for STP and NTP. Your flow meter ships with a
default STP of 25°C and 1 atm (which affects flow units beginning with “S”),
and an NTP of 0°C and 1 atm (which affects flow units beginning with “N”).
To make changes, follow these steps:
1.
Select the desired pressure or temperature reference
engineering unit by selecting
Ref temp units
or
Ref
pressure units
and pressing
CHANGE
. Both normal and
standard references use the same engineering units.
2.
Select the value you wish to modify, and press
CHANGE
.
3.
At the confirmation screen, press
SET
to confirm your change.
!
Caution:
Changes to
STP/NTP
references
will alter your mass flow readings.
