PLI PLUS™ Portable Liquid Level Gauge

Overview of the PLI Plus liquid level UT gauge

The new PLI Plus is a powerful new upgrade of our original successful PLI unit. With all the features of the original PLI design, it also has the ability to boost the power by 12, enabling cylinders to be read even when they are in poor condition, or suffering from a layer of rust.


The complete PLI Plus liquid level gauge kit includes:

  • PLI Plus liquid level gauge
  • Protective leather case and neck strap
  • Piezoelectric sensor
  • 94cm three-section telescopic extension
  • 125ml bottle of couplant
  • Full operating instructions
  • 4 x 9v PP3 batteries (2 spare)
  • Foam-lined black polymer carry case

PLI Plus Technical Specifications

  • Accuracy:  ±1.5mm
  • Features:  Power boost facility for cylinders in poor condition ~ Cylinder wall thickness selector for thick (>4mm) or thin (<4mm) walled cylinders.
  • Unit Dimensions: 200 x 100 x 40mm
  • Unit Weight: 570g (including batteries and leather case)
  • Sensor: 1.5m cable and magnetic clamp for hands-free use
  • Sensor Dimensions:  95 x 60 x 38mm
  • Temperature Range:  -10ºC to +50ºC*
  • 94cm-long extension arm
  • Power Supply: 2 x 9vPP3 batteries
  • Battery Life:  20 hours nominal with 2 PP3 alkaline batteries
  • Carry Case Dimensions: 450 x 370 x 100mm
  • Operational Weight:  680g
  • Shipping Weight:  2.5Kg

*Please note when the unit is being used to determine the level of liquid CO2, an ambient temperature of over 27ºC will not give a result, as above this temperature the CO2 changes state from a liquid to a gas.

1. Wipe clean the cylinder in the area that the sensor is to be placed and apply couplant to the sensor. Place the sensor in an area known to be above the liquid level.  Always orientate the sensor so the white dot is at the top.

2. Adjust the GAIN control until the meter shows a reading near to 10 but not above 10.

3. Place the sensor in an area known to be below the liquid level. The meter should read towards 0 but not below 0.

4. As the sensor is moved upwards towards the liquid level the meter will start to move towards 10. When the whole of the sensor footprint is above the liquid level, the meter will read 10.  When the sensor is at the liquid level the gauge reading will read a value un between 10 and 0.  What you are looking for is the large change in value between a reading below the liquid level and one above the liquid level.  A reading of approximately 5 at the liquid level is suggested.

American Bureau of Shipping Classification Society Manufacturing Process Approval
ISO 9001:2015 Certificate Number 14124458
NATO Stock Number 6680-99-517-9122
NCAGE Number U0B22
IIMS Corporate Membership Number C508
FPA Membership Number 27135
NFPA Membership Number 2800960



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