Level measurement LB 440

The measurement system LB 440 is used to monitor the level of liquids or bulk materials continuously. The non-contacting and non-intrusive measurement can easily be installed on existing reactors, autoclaves, vessels and bunkers.

LB 440 is available with proven 2-wire technology. It comprises a state of the art evaluation unit, which allows for an easy calibration and operation of the measurement and can also be used as a local display.

The system provides both, an intrinsically safe power supply and output signal. LB 440 is proven-in-use and has also applications in SIL2 graded plants.



UniSENS Detector

Rod detector with a sensitive detector length of 0.5 up to 2.0m for level and interface measurements.

CrystalSENS Detector

Point detector with high-sensitive, high-quality Sodium Iodide crystal for best long-term stability.

SuperSENS Detector

Best sensitivity on the market, is able to work with smallest source activities.


LB 440
Evaluation unit 
Power supply

115/230 VAC, ±10%, 50 ... 60 Hz, 30VA
24 VDC (18 ... 32 VDC), 30W; 24 VAC, +10%/-15%, 50 ... 60 Hz, 30 VA

Detector operating data 
Power supplySupplied by evaluation unit via a 2-wire signal cable
Housing materialStainless steel ISO 1.4301 / AISI 304
Water coolingOption (can also be retrofitted), max. 6 bar
Scintillator Size Ø x length [mm]

CrystalSENE (point detectors)

25 x 25 (NaI/Tl)
40 x 35 (NaI/Tl)
50 x 50 (NaI/Tl)


(rod detectors)

50 x 500 (polymer)
50 x 750 (polymer)
50 x 1000 (polymer)
50 x 1250 (polymer)
50 x 1500 (polymer)
50 x 2000 (polymer)

SuperSENS150 x 150 (polymer)

Ambient temperature
Operation and storage

-40 ... +60 °C (-40 ... +140 °F) for NaI/Tl and/or
-40 °C ... +55 °C (-40 ... +131 °F) for polymer
Observe possible temp. restrictions for Ex-protection!

Temperature stability

≤0,002%/ °C (-20 ... +50 °C) for NaI/Tl and/or
≤0,01 %/ °C (-20 ... +50°C) for polymer

Detector certificates & tests 
Explosion protection

II 2 G EEx de IIC T6                                     -40 ... +73 °C
II 2 D EEx de IIC T6 IP65 T80                       -40 ... +73 °C
II 2 G EEx ib IIC T6                                      -20 ... +60 °C

Class I Division 1 Group A, B, C, D                 -20 ... +50 °C

Class II Division 1 Group E, F, G                    -20 ... + 50°C

Other certificatesNepsi, TIIS, Kosha, others upon request
Signal inputs and outputs 
Signal output0/4 ... 20 mA potential-free / max. impedance 500 Ω
Digital inputsHold input
Digital outputs

1 relay for collective fault message
2 relays for min. / max. Alarm or detector temperature

InterfacesRS 232 for parameter export or PC operation using UNIBERT


Application Report
Format Size
Continuous Level measurement for cement clinker coolers en PDF 754.12 KB
Format Size
DuoSeries Detectors LB 4700 Flyer en PDF 1.44 MB
DuoSeries LB 470 Flyer en PDF 148.39 KB
Interface and Multiphase Level Measurement en PDF 1.72 MB
Level Measurement Brochure en PDF 4.85 MB
Product Data Sheet LB 440 en PDF 137.95 KB
Format Size
ATEX LB 44x en PDF 115.87 KB
ATEX LB 44x Wall Housing en PDF 212.94 KB
ATEX LB 44xx en PDF 2.45 MB
CSA LB44xx en PDF 537.73 KB
FM LB44xx en PDF 165.56 KB
TIIS LB44xx CrystalSENS en PDF 1.1 MB
TIIS LB44xx UniSENS en PDF 1.11 MB
Operation Manual
Format Size
DuoSeries LB 4700 en PDF 3.09 MB
LB 440 en PDF 4.89 MB
LB 440-RID en PDF 1.09 MB
Press & Media
Format Size
No half measures Published by Hydrocarbon Engineering, June 2017 by G. Webb. This article discusses the advantages of radiometric level measurements, also known as nuclear, measurement techniques. en PDF 1.74 MB
Product Information
Format Size
Radiation Interference Discrimination RID en PDF 434.08 KB
Technical Information
Format Size
LB 440 de, en PDF 3.1 MB