KROHNE BM 102 Handbook - Manual (Page 51)

BM 102 51
Level measurement: Level pulse amplitude and threshold
After connection to a power supply, the BM102 will:
1.
Measure reflection pulses in terms of voltage amplitude by cycling through a set of gains.
2. Identify the highest amplitude as being the product level.
This screenshot of the PCSTAR 2 F7-Oscilloscope function while measuring a typical one product
application identifies:
1 Emitted
pulse
2 Flange reflection (except coaxial probe)
3 Non-product reflection (e.g. parasite: agitator)
4 Product level reflection
5 Level threshold (with two-metre steps). Set in F11-Dynamic configuration menu
6 Offset (see below for definition)
7 Distance measured as a function of time
Offset is the distance for the signal to travel from the converter to the flange.
(the gauge’s reference point).
The level signal can be optimized by way of two factors:
Amplification factor
The amplitude of the signals is proportional to the dielectric constant of the product. At low
amplitudes the signal should be amplified. The amplification factor is dependent on the dielectric
constant and on the probe type. The device sets the gain automatically.