3 Block MEASURED VARIABLES
Device Functions Proline Promag 55 FOUNDATION Fieldbus
14
Hauser
3.3
Group
SPECIAL UNITS
3.3.1
Function group DENSITY PARAMETER
MEASURED
VARIABLES
A
⇒
MEASURING VALUES
AAA
⇓
SYSTEM UNITS
ACA
⇓
SPECIAL UNITS
AEA
⇒
DENSITY PARAMETER
070
Function description
MEASURED VARIABLES
→
SPECIAL UNITS
→
DENSITY PARAMETER
Use this function group to calculate a mass flow from a volume flow.
!
Note!
It is advisable to enter the density factor at process temperature for calculating the mass flow without compensating for
thermal expansion.
Example of calculated mass flow
without
compensation for thermal expansion of the fluid:
= 1 [dm
3
/h]
⋅
0.900 [kg/l] = 0.900 [kg/h] (mass flow at 20 °C)
= 1 [dm
3
/h]
⋅
0.783 [kg/l] = 0.783 [kg/h] (mass flow at 150 °C)
= Mass flow [kg/h]
= Volume flow = 1 [dm
3
/h]
= Density factor [kg/ l], see DENSITY VALUE function (0700)
DENSITY
VALUE (0700)
Use this function to enter a density value preferably at process temperature (or at
reference temperature). This density value is used to convert the volume flow to a mass
flow.
User input:
5-digit floating-point number
Factory setting:
1 [unit]
!
Note!
The appropriate unit is taken from the function UNIT DENSITY (0420), (see Page 13).
m
·
V
·
ρ
⋅
=
m
·
V
·
ρ
⋅
=
m
·
V
·
ρ