KROHNE OPTIWAVE 7300 C Handbook page 58

Handbook OPTIWAVE 7300 C
Level measurement
As for distance measurement above, level is influenced by
• tank height
• blocking distance
The reference point from which it is measured can be moved using
• tank bottom offset
Tank height
function C.1.2.0
Level is derived from distance and tank height (tank height - distance).
Note that when the tank has a curved tank bottom, the radar waves will reflect off the point directly below
the device. A small nonmeasureable zone is sometimes present (see diagram below). Set the tank height
above this zone: this has the advantage of setting the zero reference for level measurement above the non-
measurement zone to effectively ignore it.
Blocking distance
function C.1.9.0
As for distance measurement above.
Tank bottom offset
function C.1.11.0
Configure the device to measure product level using a reference point other than the configured tank height
(position of tank bottom in relation to the tank flange).
Move the reference point below the tank bottom by typing in a positive value (up to 50 m or 164 ft below).
Move the reference point above the default zero by typing in a negative value.
As an example, you could set the device to measure level in terms of height above sea level.
OPTIWAVE 7300 C 58