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02/2019 - MA OPTIWAVE-M 7400 C R01 en
4
OPERATION
OPTIWAVE-M 7400 C
4.4.3
How to make a filter to remove radar signal interference
If the device measures level in a tank that contains obstructions (agitator, supports, heating pipes etc.),
these objects can cause radar signal interference (parasitic signals). You can use the empty spectrum
function (menu A4.2) in the Quick Setup menu to make a filter to remove radar signal interference.
INFORMATION!
We recommend that you do an empty spectrum scan when the tank is empty and all the moving parts
(agitators etc.) are in operation.
Figure 4-7: How to make a filter to remove radar signal interference
1
Empty tank before the device uses the empty spectrum scan (with a graph of reflections shown)
2
Partially filled tank before the device uses the empty spectrum scan (with a graph of reflections shown)
3
Partially filled tank after the device uses the empty spectrum scan (with a graph of reflections shown)
4
Agitator blades location
5
Tank bottom signal
6
Agitator blades signals (interference signals) before the device does the empty spectrum scan
7
Signal of the liquid before the device does the empty spectrum scan
8
Reflected signal if the device uses the data from the empty spectrum scan. The device only uses the reflection on the surface of
the liquid to measure distance.
• After you enter Program mode, set the access level to "Expert". For more data about the procedure, refer
to
Protection of the device settings (access levels)
on page 25.
•
Push [ ], [>], [ ] and [>] to go to the menu item A4.2 Empty Spectrum.
•
Push [>] to start the empty spectrum recording procedure. For more data, refer to
Empty spectrum
recording
on page 61. Push [
^
] at the end of each step of the procedure to continue to the next step.
INFORMATION!
