Level Switch Measurement Mini-Switch LB 471

Level Switch for Min./Max. Alarm

The level switch measuring system LB 471 is used for point level measurements, providing either high level or low level alarm.

The Mini-Switch LB 471 is available with proven 2-wire technology. The measuring system includes a separate evaluation unit, ensuring easy calibration and operation procedures as well as the local display of measuring results.  

The Mini-Switch LB 471 can be operated with three different detector types:

  • Geiger-Müller tube
  • CrystalSENS NaI point detector
  • SuperSENS high-sensitive detector

As a result the perfect system configuration for each application is selected, ranging from economical to high-tech solutions.

Level Switch Measurement LB 471 - Your benefits at a glance:

• accurate and reliable
• maintenance free, no wear and tear
• long life time
• universally applicable for all container types,
   no modifications to the vessel required




SuperSENS Detector

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

CrystalSENS Detector

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


Technical Data LB 471

Evaluation Unit LB 4710



LB 4710-0XX for GM Detector
LB 4710-1XX for NaI Det. or Super-Sens


- In a 19" rack 3HE, 4TE,
  IP20 max. 19 modules for 24V
  max. 18 modules for 115/230V

- In a Cassette 3HE, 7TE, IP 20
  for any 19" rack

- In a wall mounted housing, IP 66
  max. 3 modules

Power supply

18-30V DC or 24V AC +10% -15%

option: 115/230V AC transformer
            +10% / -15%, 47-65Hz

Power consumptionmax. 4W per module
Operating temp.-30 ... + 60°C (-22 ... 140 °F)

Storage temp

-40 ... + 70°C (-40 ... 158 °F)
keep dry!

Weight0,3 kg per module

Detector connection 

2 wire
option: intrinsically safe [EEx ib] IIC

Digital In

for external empty

Digital Out



contact load

1 relay for min./max. (SPDT)
1 relay for failure signal
1 relay for warning signal
  alternative as min./max. usable

AC: max. 250V, max. 1A, max. 200VA
DC: max. 300V, max. 1A, max. 60W
ohm resistive load


2 lines LCD illuminated

each line 4 digits

keyboard for data entry

keyboard lockable via password

Time constant

0,5 - 999s

Decay compensation

automatic, for Co-60 and Cs-137


buffered with capacitor
running period without power supply: approx. 1 Month

Certificatefor overcharging in vessels which are used for storage water-endanger fluids according WHG


Format Size
LB 471 Level Switch Mini-Switch en PDF 352.55 KB
Format Size
ATEX LB 3171 Typ / SZ5‐GHS‐3171 en PDF 2.45 MB
ATEX LB 471 en PDF 637.39 KB
ATEX LB 3171 Typ / SZ5‐GHS‐3171‐ en PDF 1.04 MB
CSA ATEX LB 3171 Typ / SZ5‐GHS‐3171 en PDF 59.89 KB
Kosha LB 3171 Typ / SZ5‐GHS‐3171 en PDF 675.79 KB
LB 4700 ATEX en PDF 2.27 MB
LB 4700 CE Conformity-Ex en PDF 1.08 MB
LB 4700 CE-Conformity Non-Ex en PDF 1.01 MB
Nepsi LB 3171 Typ / SZ5‐GHS‐3171 en PDF 709.53 KB
Operation Manual
Format Size
LB 471 Level Switch en PDF 6.41 MB
LB 471 Level Switch / Russian version en PDF 7.59 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
Project Questionnaire
Format Size
Level Switch en PDF 109.14 KB
Software Tool
Format Size
LB 4700 DuoSeries Embedded Software Update Version: 12.06.12 de, en ZIP 250.03 KB
LB 4700 DuoSeries PC-Program for Service Modem Version 1.0.3 (compatible with embedded 12.06.12) de, en ZIP 1.84 MB
Technical Information
Format Size
LB 471 GM-Detector en PDF 721.78 KB
LB 471 NaI-Detector en PDF 724.48 KB
LB 471 Super-Sens Detector en PDF 1000.31 KB