Table 4-37 Mass Flow Prompts - Honeywell VRX180 User Manual

Programming Function Blocks and Features
Mass Flow
By compensating for variations in fluid temperature and pressure, Mass Flow is used to obtain a more
precise fluid flow measurement from an orifice plate developing a differential pressure. The output CVn
OV is mass flow and is calculated from the following formula for U.S. Units Of Measurement:
MF = FACTOR 1 x SQRT [DP INPUT x (PRESSURE INPUT+14.7) / (TEMPERATURE INPUT + 459)]
where
FACTOR 1 is calculated by user
DP INPUT is differential pressure in inches of water
PRESSURE INPUT is in PSIG
TEMPERATURE INPUT is in °F
Or, Mass flow is calculated from the following formula for International Units Of Measurement:
MF = FACTOR 1 x .569 x SQRT [DP INPUT x (PRESSURE INPUT +101.4)/(TEMPERATURE INPUT + 273)]
where
FACTOR 1 is calculated by user
DP INPUT is differential pressure in KPASCALS
PRESSURE INPUT is in KPASCALS
TEMPERATURE INPUT is in °C
Table 4-37 describes the Mass Flow prompts. See Table 4-2 for additional prompts.
Prompt
OUT LOW LIMIT
OUT HIGH LIMIT
DP INPUT
PRESSURE INPUT
TEMP INPUT
UNITS OF MEASURE
FACTOR 1
128

Table 4-37 Mass Flow Prompts

Range/Selections
OFF or number
OFF, analog parameter,
number
OFF, analog parameter,
number
OFF, analog parameter,
number
US or International
OFF, analog parameter,
number
Video Recorder – User Manual
Definition
Displayed output value will be clamped and will flash
when these limits are exceeded.
Differential pressure input
Pressure input in PSIG or KPASCALS
Temperature in °C or °F
Units of measure
Flow factor for the particular installation