Sequoia Scientific


Low-Cost Particle Size Analyzer

The LISST-Portable|XR is the world’s first and only battery powered, portable, low-cost particle size analyzer. It can be used in the field, in the laboratory or on the factory floor.

The LISST-Portable|XR analyzes the sample in a wet state to obtain the particle size distribution and the particle volume concentration. The LISST-Portable|XR uses the same laser light scattering method (laser diffraction) as popular laboratory particle size analyzers.

It has all the features and performance of a laboratory instrument but in a self-contained, portable, low-cost enclosure that allows you to make measurements where it’s needed, when it’s needed.

For a list of select customers in Drilling and Hydropower, click here.


  • Low-cost
  • Truly portable – completely self-contained with built-in data logger, processor, rechargeable battery, and 7” color touch screen display.
  • Mixing chamber that keeps large and heavy particles suspended.
  • Shock mounted optics block that can withstand the rigors of field use.
  • Built-in ultrasonic probe for complete sample dispersion.
  • Touch panel allows for easy SOP programming, sample analysis and display of data without a PC.
  • Multiple Mie models as well as Fraunhofer model available for inversion, selectable from the touch panel
  • All data-processing is performed on board and stored in ASCII format. No post-processing necessary.
  • Outputs: Total volume concentration, mean size, standard deviation, optical transmission, D5, D10, D16, D25, D50 (median grain size), D60, D75, D84, D90, D95, D60/D10 (Hazen uniformity coefficient), particle surface area, silt fraction, silt volume, size distribution, battery voltage, sample notes.
  • Based on the laser diffraction principle.
  • View the LISST-Portable|XR brochure!

For more than 20 years, Sequoia Scientific has been making submersible, battery powered laser diffraction particle size analyzers. We have taken the knowledge learned from building submersible instruments and applied it to a truly portable particle size analyzer that is just as happy on a lab bench as it is next to a flowing stream on a rainy day. The LISST-Portable|XR is the fourth generation of LISST-Portable. With this latest generation we have made many improvements to make the instrument easier to use as well as increase the performance such as measuring smaller particles and adding features such as the built-in ultrasonic probe.

Why do I need a low-cost, portable particle size analyzer?

LISST-Portable|XR in ship caseThere are many applications where having a portable instrument is very helpful. Making measurements of samples from a small stream without sample handling issues or measuring drilling fluid on the drill site for faster results are two examples. However, having a portable instrument is also useful even if you only plan to use it in a lab environment. For example, you might have a need to measure particle size at multiple facilities but the cost of laboratory particle size analyzers is too high to justify one instrument at each location. Moving these instruments from place to place is not easy and takes too long. The LISST-Portable|XR can be easily moved from location to location with no setup. Open the lid, turn it on and you are ready to go. When you are done with it, just store it under the bench or in a cabinet until it is needed.   The costs in money and manpower for labeling, tracking, transporting, storing, and processing samples can be high. Making measurements right at the source can eliminate these costs while providing instant actionable data.

Please email us for price information or to request a demonstration!!

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One of the key features of the LISST-Portable|XR that sets it apart from other particle size analyzers (in addition to being truly portable) is how easy it is to use.   Upon powering up the instrument the first thing you will see is the large 7” Touch Screen. This touch screen walks the operator through the process of collecting a measurement and displays the results for immediate evaluation. No computer is require to take measurements or view results. The results are stored on the instrument and can be downloaded later to generate a formal report. The ease of use combined with the configurable standard operating procedures makes it possible to have non-experts consistently and accurately measure particle size.

Screen shot: Home page Screen shot: PSD results

A more detailed introduction to the user interface can be found on the LISST-Portable|XR video page. There are two videos related to the user interface. One is on “How to make a Measurement” and the other is an “Intro to the Main Menu”.

Measurements are saved on-board the instrument and can be viewed on the screen at any time.  Connect the LISST-Portable|XR to a PC using the provided USB cable to offload the processed results.  Using a customizable Excel template a formal size distribution report can be generated and printed or saved as a PDF.  An example of the Size Distribution Report can be found here.

The core technology used by the LISST-Portable|XR is laser light scattering or laser diffraction. This method is one of the most common ways of measuring particle size. There are many companies using this method including Malvern, Horiba, Cilas, and others. The performance of the LISST-Portable|XR is equal to the laboratory instruments but in a completely portable package. The LISST-Portable|XR is compliant with the ISO-13320-1 standard for laser diffraction measurements.

Be sure to visit the Frequently Asked Questions and Gallery sections of this page.

LISST-Portable|XR with ultrasonic probe inserted

 Please email us for price information or to request a demonstration!!

Request Quote



 Particle Size Range
  • 0.34-500 µm size range in 44 log-spaced size classes
Particle Concentration Range
  • Concentration range 30-1,900 mg/l. NOTE: Actual range is dependent on the grain-size and size distribution of the suspended particles. See table below for details and examples of concentration ranges based on measurements using ISO particle standards and easily obtained reference materials. SMD: Sauter Mean Diameter.

    SSC [mg/l] @ 98% optical transmission

    SSC [mg/l] @ 75% optical transmission 





    ISO Fine (ISO 12103-1,A2)







    ISO Coarse (ISO 12103-1,A4)







    Whitehouse 20-30 µm glass beads







    Sieved sand 75-125 µm







Mechanical and electrical
  • Instrument Dimensions: 7” tall x 11.5” deep x 17.5” wide (17.7 cm x 29cm x 44.3cm)
  • Shipping Dimensions: 31″ x 21″ x 11″
  • Weight: 15 lbs (7 kgs)
  • Shipping weight: 50 lbs (23 kgs)
  • Internal Data Storage: 1 GB, > 100,000 size distributions
  • Battery life: 8 hours nominal (depends upon sampling rate)
  • Battery: Lithium-Ion, two batteries, 76 Whr each (serial numbers 610 and below: 58Wh each).
  • External power supply/charger: 100-250V input, 15V output. CE marked.
  • Operating temperature: 0 to 40 C
  • Storage temperature: -20 to 50 C (no fluid in reservoir)
  • Communications: via USB, using supplied software.


LISST-Portable|XR Item # and Description

Item #DescriptionThumbnail
SEQ-FP-LPXRLISST-Portable|XR Portable Particle Size Analyzer
0.34 um - 500 um size range. Built-in ultrasonic probe. Includes 110 / 220 VAC power supply and charger, built-in mixing chamber, integrated ultrasonic probe for complete particle dispersion, 7" touch panel display for programming, analyzing and displaying data, rechargeable battery, and communication cable and shipping box. Includes Windows software for data offload and report preparation. Ships in a Pelican shipping container with custom foam cushioning (SEQ-AC-LPXR-SC).
Must be purchased together with new instrument.
No picture
One-time service of instrument within 36 months after delivery.
Includes one-way return shipping from Sequoia, all evaluation, diagnosis, testing and calibration.
Parts and labor for repairs not included.
Must be purchased together with new instrument.
NOTE: End-user responsible for return shipment DDP to Sequoia.
No picture

LISST-Portable|XR Replacement Part #'s and Descriptions

Item #DescriptionThumbnail
SEQ-AC-LPXR-CBLCharger, serial communication and charging cable for LISST- Portable|XR
With USB connector and built-in serial-USB adapter.
NOTE: Included with all new LISST-Portable|XR instruments.
SEQ-AC-LPXR-SCReplacement Ship Case for the LISST- Portable|XR
Includes foam insert for LISST-Portable|XR instrument and toolbox.
LISST-Portable|XR in ship case
SEQ-AC-LPXR-USTIPReplacement Ultrasonic Probe Tip for LISST- Portable|XR
Replacement ultrasonic probe tip for LISST-Portable|XR.
SEQ-AC-LPXR-LIDSReplacement Lids for LISST-Portable|XR
Clear lids and ultrasonic holder for LISST-Portable|XR including O-rings.
LISST-Portable|XR lid and ultrasonic holder
SEQ-AC-LPXR-ARFAccessory Refill Kit
Includes funnel w/4 oz Cap, Tubing 1/4" ID x 3/8" OD, Buna-N O-Rings, Glass vial with sample particles, KimWipes, Cleaning sticks.


Can you measure dry particles with the LISST-Portable|XR?

Yes and No. The LISST-Portable|XR is designed to measure particles suspended in a clear liquid. It is not designed to measure dry particles in air. However, if you can put a small amount of the particles in a compatible liquid, such as water or isopropyl alcohol, it is be possible to measure them with the LISST-Portable|XR.

Do you have to use water as the dilution fluid?

Water is the suggested liquid to be used when measuring particles. However, other fluids can be used. For example Isopropyl Alcohol (IPA) is commonly used with the LISST-Portable|XR when making measurements of oil based drilling fluids (OBM) or cement. Other fluids might be possible but they need to be compatible with the plastics (acrylic) in the instrument and the optical properties must be known. If the optical properties are significantly different from water, special firmware modifications may be required.

Does the LISST-Portable|XR require annual calibrations or maintenance?

The LISST-Portable|XR does not require recalibration. It is calibrated at the factory and automatically compensates for changes over time. There is no annual maintenance is required.

Are there any spare parts recommended or required?

There are no required spare parts. Some customers have purchased a spare set of lids for the test chamber and replacement titanium ultrasonic probes. The lids could get lost and the titanium ultrasonic probe will eventually wear down and lose performance. However, these items can be purchased separately at any time.

What is required to switch from using water to using Isopropyl Alcohol (IPA) as a dilution fluid?

The optical properties of water and IPA are very similar. There is no need to change any of the settings on the instrument when switching between water and IPA. However, you must rinse the chamber with the fluid you plan to use for measurements multiple times to make sure there is no traces of water or IPA remaining. A small amount of water in the IPA (or vice versa) will produce excess scattering that will affect the measurement. This effect will result in a warning when the background scattering is measured, which is part of a typical measurement protocol.

The LISST-Portable|XR uses lithium batteries. Does this cause problems for shipping by air freight?

The LISST-Portable|XR uses two lithium batteries that are sized to be below the limit considered hazardous as per the “Lithium Battery Shipping Guidelines” published by the IATA. Some special labeling is required on the shipping box but it does not require special hazardous goods documentation. The shipping case for the LISST-Portable|XR has the required labels pre-installed.

Can I rent the LISST-Portable|XR?

Yes. Sequoia has a rental unit available. The minimum rental period is one (1) month and the first month’s rent must be prepaid in full before the instrument is delivered. Subsequent months are invoiced at net 30 days payment terms. User must pay for the return shipping to Sequoia, and insure the instrument for the full price for the duration of the rental period as well as the return shipping.

If you decide to purchase a new instrument within 90 days after the return of the rental unit you can apply 85% of what you already paid in rental fees towards the cost of the new instrument.

Call for a draft rental agreement.