Level Instrumentation > Transmitters > Siemens SITRANS Probe LU


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Siemens SITRANS Probe LU Ultrasonic Level Transmitter

Siemens took the experience of 190,000 Milltronics Probe applications and used it to build a stronger, more versatile ultrasonic level measurement tool. Siemens SITRANS Probe LU is a two-wire, loop-powered unit that includes automatic false-echo suppression, Milltronics' patented Sonic Intelligence echo processing, and a variety of digital communications and programming options into a single unit. The Probe LU is ideal for level monitoring in the water and wastewater industry and chemical storage vessels, and can reliably monitor level, volume, and flow of liquids in open channels, storage vessels, and process vessels.

The transducer on the Probe LU is available as ETFE or PVDF to suit the chemical conditions of your application. For applications with varying material and process temperatures, the Probe LU incorporates an internal temperature sensor to compensate for temperature changes. The Probe LU offers two communications options: HART® or PROFIBUS PA (Profile v3.0, Class B).

Key Specifications

  • Proven Ultrasonic Technology: Replaces Milltronics' "The Probe"
  • Low Noise Transmitter and Low Noise Shield for High Signal-to-Noise Ratio
  • Stronger Signal (+30 dB) for Monitoring Level, Volume, and Flow of Liquids and Slurries in Storage and Simple Process Vessels, and Open Channels
  • Patented Self-Learning Algorithm Ignores False Echoes from Fixed Obstructions
  • SIMATIC PDM and HART Communications Standard for Remote Programming
  • Short Blanking Distance, Even at Long Ranges
  • Click here to view our full offering of Siemens Milltronics level instrumentation

Specifications, Manuals, and Supporting Literature

Model Selection Guide

Use this table to find the right model for your application.  Don't see the option you need? Call a Lesman sales specialist at 800-953-7626

Make one choice from each table section. A complete catalog number will look like this: 7ML5004-_ _ _ _ _

Description Catalog
SITRANS Probe LU: Ultrasonic Level Transmitter 7ML5221-
Range 20 Ft (6 M) ETFE
20 Ft (6 M) PVDF Copolymer
40 Ft (12 M) ETFE
40 Ft (12 M) PVDF Copolymer
2A_ _ _
2B_ _ _
2C_ _ _
2D_ _ _
Communications HART® and 4-20 mA Output
Profibus PA
_ _A1_
_ _A2_
Approvals General Purpose FM, CSA, CE
FM Class I, Div 2
Intrinsically Safe (HART®) FM/CSA
Intrinsically Safe (Profibus) FM/CSA
_ _ _ _1
_ _ _ _4
_ _ _ _8
_ _ _ _5
Accessories Intrinsically Safe Handheld Programmer
Universal Mounting Adapter for 3" Flange, 2" NPT
SITRANS Probe LU Instruction Manual
SITRANS Probe LU Quick Start Guide
SIMATIC PDM v8.1 Software Utility for Configuring, Commissioning 
   and Diagnostics; (Profibus, HART®, 4 Tags)


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