KROHNE OPTIWAVE-M 7400 C Short Manual page 47

OPTIWAVE-M 7400 C
Menu Function
No.
C2.3 Epsilon R Gas
C2.4 Measuring
Mode
C2.5 Overfill
Detection
C2.6 Overfill
Threshold
02/2019 - MA OPTIWAVE-M 7400 C R01 en
Function description
A major parameter for radar level
measurement devices. This can be applicable to
high pressure applications or tanks that contain
a specified gas. If the gas is not 1.0, set the
ε value to the ε value of the gas.
r r
Minimum access level to change the
setting: Expert
In "Direct" mode, the level signal is a reflection
on the surface of the tank contents. If the
dielectric constant is very low, the device uses
"TBF Auto" or "TBF Full" mode. The device in
"TBF" mode uses the radar reflection on the
bottom of the tank (the signal goes through the
tank contents). The tank must have a flat
bottom for the device to operate correctly in
TBF mode. This menu item is set by default to
"Direct" for tank contents with an ε
is very low (<1.4), use "TBF Full". If εr is low (ε
ε
r
= 1.4. 1.5), use "TBF Auto" mode.
"TBF Auto" is an automatic mode that lets the
device make a selection between "Direct" mode
and "TBF" mode. If you use "TBF Full" or "TBF
Auto", enter the dielectric constant in menu
item C2.2 Epsilon R Product.
Minimum access level to change the
setting: Expert
If this function is in operation, the device will
monitor the level even if it is in the blocking
distance. The output shown on the display
screen stays fixed at the blocking distance, but
an error message will warn the user that the
tank is too full.
Minimum access level to change the
setting: Expert
If you have set menu item C2.5 Overfill
Detection to "Enabled", this menu item will be
available. If the device cannot easily measure in
the blocking distance (see menu item C1.5),
then you can change the overfill threshold. This
value is a percentage of the radar signal
amplitude. To enter the correct value, we
recommend that you speak or write to your
supplier.
Minimum access level to change the
setting: Expert
www.krohne.com
Selection list
1.0...20
Direct, TBF Auto, TBF Full
>1.4. If
r
r
Disabled, Enabled
min-max: 0.0.
100.0%
OPERATION
4
Marine Default
1.0
Direct
Disabled
1
10%
47