Electrolab 2100 Series Flex Level Sensor is a patent-pending flexible, rugged, chemically and abrasion resistant digital level sensor for reliable tank monitoring. A bend radius of 36″ makes the RU Flex Sensor a one-man installation job. Electrolab RU Flex Level Sensors are able to measure fluid levels and temperature measurements through a single tank port. The user is able to measure one or two levels with an additional third level with high-level alarm and shut-in option. The high-level alarm shut-in requires no power and, unlike competitors’ sensors, is not affected by power outages. Available in three measurement increments and lengths between 2 and 48 feet.

Product Detail

Hose Material:

  • A proprietary, patent-pending, flexible hose with multi-layer barrier properties for use in difficult environments

Measurement Length:

  • 2 – 48 feet


  • Explosion Proof 2110EX (12V or 24V), L-standard, C, T or no housing

Level Measurement Increments:

  • 1/8-in. resolution; +/- 3/16-in. accuracy (Stainless Steel only)
  • 1/4-in. resolution; +/- 1/8-in. accuracy
  • 1/2-in. resolution; +/- 1/4-in. accuracy
  • +/- 0.1% repeatability

Coiled Diameter:

  • Approximately 36-inch diameter (will vary slightly with the length of the sensor)


  • NYTROPHYL stainless steel
  • Two piece floats for field installation and replacement
  • One float used for product level
  • One float for water interface level
  • Designed to fit through a three-inch NFPT tank port
  • Operating Temperature Range: -40 degrees C to 80 degrees C

Temperature Measurement:

  • 12 inches from bottom
  • +/- 1.5 degrees C accuracy
  • Up to 8 distinct temperature measurements (one standard)

Power Requirements:

  • 5.6 VDC to 13 VDC

Power Consumption:

  • 15 mA nominal 20 mA maximum


  • 40 psi: standard


  • Modbus RTU 16-bit unsigned integer
  • Modbus RTU 32-bit floating point
  • Modbus RTU 2 x 16-bit
  • Serial Data via ASCII

Anchor Weight:

  • 3 in. diameter, required weight varies based on sensor length


  • 18 AWG recommended for digital circuits


  • Class I, Div. 1, Group D hazardous locations (when used with the Explosion Proof Housing or used with a standard housing and connected to an approved intrinsically safe barrier device)


  • ANSI/UL-913, 7th Edition
  • CAN/CSA C22, No. 157


Open communication protocols allow Electrolab’s RU Flex 2100 DLS to interface with most manufacturers’ equipment. We offer:

  • RS485
  • Two- or four- wire communications
  • Baud rate and parity programmable
  • 4-20mA signal available when connected to an Electrolab 3010 digital-to-analog converter board
  • Wireless compatibility with preferred partners


  • High-Level Shut-In with or without test fixture

SKU Legend:

RU-Flex DLS 2100 Sensor: UFXAABCCTdFe

  • UFX = Indicates sensor material is UHMW.
  • AA = Length of sensor in units of feet (Ft.)
  • B = Material of sensor (U for UHMW)
  • CC = Resolution (50, 25, or 12)
  • Td = Number of temperature sensors (Example: T1)
  • Fe = Number of floats (F1 for single float option; F2 for dual float option)
  • If an order is HLS, the SKU will have an H (HLS w/ test apparatus) or HO (HLS w/o test apparatus) at the end:
  • UFX20U50T1F2H
  • UFX16U50T1F2H0