ABB LWT300 Series User Manual page 57

Setting a blocking distance
The blocking distance is the distance where you do not want the instrument to take measurements
because you know that these measurements will include erroneous or useless data (e.g., right at the
junction between a nozzle and the inside of the vessel, where a giant pulse usually forms.)
To set a blocking distance:
1 Select Device Setup > Safety Setting > Blocking distance.
2 Press Edit.
3 Set the necessary blocking distance and press OK.
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Figure 40 Blocking and safety distances
Sensor reference
point
Setting a safety distance
The safety distance is a specific distance where you can take measurements, at levels preceding the
blocking distance, in case you might want to be informed when such levels are reached.
To set a safety distance:
1 Select Device Setup > Safety Setting > Safety distance.
2 Press Edit.
3 Set the necessary safety distance and press OK.
Activating a safety distance related alarm
You can raise an alarm when the safety distance threshold is reached.
To to so:
1 Select Device Setup > Safety Setting > Safety Dist. Reaction.
2 Press Edit.
3 Highlight Alarm and press OK.
Nozzle length
Blocking distance
Safety distance
Configuring the instrument
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