KROHNE MFC 400 EN - Manual (Page 95)

OPERATION
6
95
MFC 400
www.krohne.com 08/2013 - 4002075802 - MA MFC 400 R02 en
6.5.6 Density mode (menu C1.2.2)
There are 4 available operating modes for density that can be set here:
• Process:
The device measures and displays the current operating density of the product.
• Fixed:
The device displays a fixed density value. This value must be entered in menu C1.2.3.
• Referred:
The device calculates the density based on a set reference temperature.
• Standard:
The device calculates the standard density based on a set reference temperature and the
correction factors k
0
...k
2
, so that a standard volume can be output.
The following equation is used for the "Referred" mode: The following equation is used for the "Referred" mode: The following equation is used for the "Referred" mode: The following equation is used for the "Referred" mode:
ρ
r
= ρ
a
+ a (t
a
- t
r
)
ρ
r
= Density at reference temperature
ρ
a
= Current measured operating density at current operating temperature
a = Programmed temperature coefficient/density gradient
t
a
= Current measured operating temperature
t
r
= Reference temperature
The reference temperature must be entered in menu item C1.2.3. The density gradient is set in
C1.2.4.
The following equation is used to calculate the density gradient: The following equation is used to calculate the density gradient: The following equation is used to calculate the density gradient: The following equation is used to calculate the density gradient:
a = (ρ
D
- ρ
C
) / (T
B
- T
A
)
The value for the density gradient is generally positive as an increase in temperature usually
reduces the measured density(exception: water anomaly).
Figure 6-7: Calculating the density gradient
1 Density
2 Temperature
.book Page 95 Monday, August 26, 2013 9:05 AM