KROHNE BM 700 EN - Manual (Page 13)

BM 700 Installation and Operating Instructions Page 13
Empty-tank spectrum
To enable the BM 700 to identify and blank out interference signals, e.g. caused by
fixed and moving tank internals, the tank profile (empty-tank spectrum) needs to be
recorded once only prior to (initial) start-up. For recording, the tank should be
completely empty and all moving parts (e.g. agitators) switched on. If major inter-
ference through internals is not expected, recording of the empty-tank spectrum can
also be dispensed with, since the factory has already carried out and stored a partial
empty spectrum of the flange system.
Empty-tank spectrum recording via display
After selecting menu item Fct. 3.5.2, press key
→
. The display then shows whether
the empty spectrum is currently ON or OFF. Then press the
↵
key if no change is to
be made, or use the
↑
key to choose between the following options:
•
ON: the empty-tank spectrum is (again) switched on and taken into account for
measurements.
•
OFF: the empty-tank spectrum is not taken into account for measurements, but
remains stored in the BM 700 and can be switched on again at a later date.
•
RECORD: the existing empty-tank spectrum is to be deleted and a new one
recorded.
After selecting "RECORD": if other parameters had previously been changed, the
query "ACCEPT YES" is first made as to whether they are to be stored. In this case,
confirm by pressing
↵
. To record, use the
↑
key to select one of the following options:
•
MAX. VALUES: (only maximum values are taken into account when the empty-
tank spectrum is recorded; useful e.g. with “difficult“ agitators).
•
AVERAGE: (values are averaged; this setting can be used for most
applications).
After selecting with the
↑
key, press the
↵
key to select TOTAL or the
↑
key to select
PARTIAL.
•
When TOTAL is selected, the empty-tank spectrum is recorded over the entire
range (tank height).
•
If the tank has not been fully drained, the empty-tank spectrum can also be
recorded up to a certain distance, in which case the menu item PARTIAL should
be selected. When this has been selected, a query takes place by way of the
↵
key concerning the distance value up to which the empty-tank spectrum is to be
recorded. The tank area below the current filling level is then excluded from the
empty-tank recording. It is recommended to maintain a safety distance of 20 to
30 cm from the actual product distance.
Subsequently press key
↵
to start recording the empty-tank spectrum. The display
starts with “1000“ and counts down to “0“. The sign WAIT flashes in the display.
READY appears after approx. 2 minutes. Then press key
↵
five times to store the
recorded empty-tank spectrum, which is taken into account for measurements.??
Empty-tank spectrum recording via PC-CAT
Connect the BM 700 and press in the display mode of PC-CAT the key combination
Ctrl-L. The type of empty-tank spectrum can be selected by one of the following keys:
1: Max.Values 4: Max. Partial A: Break
2: Average 5: Avg. Partial