User Manual
OPERATION
6
67
OPTIWAVE 7400-24 C
www.krohne.com12/2015 - 4003518001 - MA OPTIWAVE7400-24-R01-en
2.5.2 STILLWELL D. The inner diameter of the stilling well. If the
device is installed in a stilling well or has a
Wave-Guide antenna, enter the diameter.
The device will use this data if you set 2.3.4
STILLWELL EN. to "Yes". This menu item is
not shown if you set 2.3.4 STILLWELL EN. to
"No".
min-max: 22...999 mm /
0.9...39.3¨
1
2.5.3 TRACING VEL. Maximum tracking velocity. This value must
agree with the maximum rate of change of
the level of the liquid in the tank.
min-max:
0.1…10.0 m/min
0.5 m/min
2.5.4 MEASUR.MODE The device uses the dielectric constant (ε
r
)
of the tank contents to monitor level. In
direct mode (if the dielectric constant is
high), the level signal is a reflection on the
surface of the tank contents. If the dielectric
constant is low, the device uses TBF 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
r
>1.8. If ε
r
is very low
(<1.6), use "TBF Full". If ε
r
is low (ε
r
=
1.5...1.7), use "TBF Partial" mode. "TBF
Partial" is an automatic mode that lets the
device make a selection between "Direct
mode and "TBF" mode. If you use "TBF Full"
or "TBF Partial", enter the dielectric
constant in menu item 2.5.3 Er PRODUCT.
Refer also to "Measuring principle" on page
90.
Direct, TBF Partial, TBF
Full
Direct
2.5.5 Er PRODUCT For measurement in TBF mode only. The
device automatically calculates the level
based on the product ε
r
. If you select "TBF
Partial" or "TBF Full" in menu item 2.5.4
MEASUR.MODE, you can change the ε
r
value
manually to adjust readings.
min-max: 1.100 to 10.000 2.000
2.5.6 OVERF. ENAB. If this function is in operation, the device will
monitor the level even if it is in the blocking
distance. The reading shown on the display
stays fixed at the blocking distance if the
level is higher than the blocking distance.
The output will show that the tank is full. An
error is recorded by default.
If this function is not in operation, the
device looks for the largest signal between
the process connection and the tank bottom.
YES, NO NO
2.5.7 OVERF.
THRESH.
The overfill threshold. TBD.
Menu
No.
Function Function description Selection list Default