Honeywell VRX180 user manual Mass Flow Prompts

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 xSQRT [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.

Table 4-37 Mass Flow Prompts

Prompt	Range/Selections	Definition
OUT LOW LIMIT	OFF or number	Displayed output value will be clamped and will flash
		when these limits are exceeded.
OUT HIGH LIMIT
DP INPUT	OFF, analog parameter,	Differential pressure input
	number
PRESSURE INPUT	OFF, analog parameter,	Pressure input in PSIG or KPASCALS
	number
TEMP INPUT	OFF, analog parameter,	Temperature in °C or °F
	number
UNITS OF MEASURE	US or International	Units of measure
FACTOR 1	OFF, analog parameter,	Flow factor for the particular installation
	number

128 Video Recorder – User Manual