SonTek-SL Series

SonTek-SL Mounting Frame Assembly

Demonstrated is the SonTek-SL basic kit includes a 1.2m (4ft) length mounting frame section, slide assembly with adjustable angle mounting plate, and handle bar.

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Inspired by the need for a SIMPLE way to measure water velocity and level in open channels, the SonTek-SL (affectionately known as the Side-Looker or "SL") has earned worldwide acceptance as a long-term monitoring solution. Now, with two new (3G) models turbo-charged by our proprietary SmartPulseHD®, the SonTek-SL features accessories, mounting options, software, and various integration formats to ensure it fits your application.

Designed specifically for side mounting on bridges, canal walls, or riverbanks, the SL's SLEEK, low-profile housing, makes installation easy.  With three models to choose from, the SL can be used in channels as small as you can jump across rivers as wide as the Amazon. Ultra-narrow beam widths combined with unmatched side lobe suppression provide the SUPERIOR acoustic directivity necessary for achieving maximum horizontal range free of interference from surface or bottom boundaries.

  • Overview

    First-time users can collect test data within minutes of receiving the SonTek-SL. Deployments require only a few minutes to configure the SL and collect data. This system provides the highest quality Doppler velocity data without requiring the user to become an expert on Doppler technology.

    Argonaut SL500 Velocimeter Brazil


    Water Velocity and Level: Water velocity, level, flow, and total volume-multiple parameters from one easy-to-use instrument. Acoustic Doppler profile of velocity data and acoustic water level offers the most accurate, reliable measurements.

    SmartPulseHD®*: An intelligent algorithm that looks at water depth, profiling range, velocity, and turbulence and then acoustically adapts to those conditions using pulse-coherent, broadband, and incoherent techniques.  Best data possible under any condition.  High-def cell sizes down to 4 cm.

    Compact, Hydrodynamic Design: Incredibly lightweight and easy to transport and mount.  The slim shape is easy to maintain, stays clean, increases available sample area, and fits into more places.

    Water Velocity Profiling: Customizable, flexible setup options to suit various applications. 3G models offer 128-cells for high-resolution and detailed profiles.

    Acoustic-Pressure "Duo" Water Level (3G models only): Not only are redundant sources of water level, the acoustic vertical beam, and pressure sensor continually self-check, and pressure data are auto-corrected to keep atmospheric offset negligible.

    Versatile, Easy Mounting:  Easy-access side mounting reduces concerns over personnel safety, lowers operational costs by avoiding divers and boats, avoids interruption in facility operations, and avoids interruption in data and water delivery to clients and stakeholders. 

    Wave Spectra Option: Integrated pressure sensor calculates and outputs wave height and period in real-time. (SL-500 model only.)

    *SL1500/3000 3G models only. Patent pending.

  • Specifications
    SL3000 (3G) SL1500 (3G) SL500
    Sampling range 0.1 to 5m | 0.3-17 ft   0.2 to 20m | 0.7-66 ft    1.5 to 120m | 5-400 ft     
    Minimum Channel Width  0.5m | 1.6 ft 1.0m | 3.3 ft 6.5m | 21 ft
    Acoustics — Horizontal Beam Width•• 1.4° 1.4° 1.4°
    Acoustics — Vertical Beam Width•• 1.4° 2.9° 3.8°
    Acoustics — Side Lobe Suppression >60dB >60dB >60dB
    Multi-cell Velocity Profiling  Up to 128 cells Up to 128 cells Up to 10 cells
    SmartPulse HD® Yes Yes N/A
    SonTek Compass/Tilt Tilt Tilt Compass/Tilt
    Internal Nonvolatile Memory 4GB 4GB 4MB
    Water Velocity — Range ±7 m/s | 23 ft/s ±7 m/s | 23 ft/s ±6 m/s | 20 ft/s
    Water Velocity — Resolution 0.001 m/s | 0.003 ft/s 0.001 m/s | 0.003 ft/s 0.001 m/s | 0.003 ft/s
    Water Velocity — Accuracy ±1% of measured velocity;
    ±0.005 m/s | ±0.015 ft/s
    ±1% of measured velocity;
    ±0.005 m/s | ±0.015 ft/s
    ±1% of measured velocity;
    ±0.005 m/s | ±0.015 ft/s  
    Water Level — Vertical Beam Range 0.1 to 5m | 0.3 to 17 ft 0.15 to 10m | 0.5 to 33 ft 0.2 to 18.0m | 0.7 to 59 ft
    Water Level — Vertical Beam Accuracy Depth <3m: ±0.3cm | 0.01 ft
    Depth ≥3m: ±0.1%
    Depth <3m: ±0.3cm | 0.01 ft
    Depth ≥3m: ±0.1%
    Depth <6m: ±0.6cm | 0.02 ft
    Depth ≥6m: ±0.1%
    Pressure Sensor — Range 30 m 30 m 20 m
    Pressure Sensor — Accuracy FS 0.10% FS 0.10% FS 0.25% FS
    Wave Height Spectra No No Optional
    Temperature Sensor — Resolution ± 0.01º C ± 0.01º C ± 0.01º C
    Temperature Sensor — Accuracy ± 0.2º C ± 0.2º C ± 0.01º C
    Power Input 9-15 VDC 9-15 VDC 7-15 VDC
    Power Consumption§ 0.8 W 1.0 W 0.7 to 1.0 W
    Weight in Air 0.45 kg | 1.0 lb 0.90 kg | 2.0 lb 6.0 kg | 13.2 lb
    Weight in Water 0.15 kg | 0.3 lb 0.2 kg | 0.5 lb 1.1 kg 2.5 lb
    Pressure Rating & Maximum Depth 30 m | 98 ft 30 m | 98 ft 30 m | 98 ft
    Mounting Plate Dimensions 25 x 17 x 1 cm | 10 x 6.7 x 0.4 in 25 x 17 x 1 cm | 10 x 6.7 x 0.4 in 35.5 x 22.9 x 1.5 cm | 14 x 9 x 0.6 in
    Operating Temperature -5° to 60°C | 23° to 140°F -5° to 60°C | 23° to 140°F -5° to 60°C | 23° to 140°F
    Storage Temperature -10° to 70°C | 14° to 148°F -10° to 70°C | 14° to 148°F -10° to 70°C | 14° to 148°F
    Communications — Standard Protocols RS232/SDI-12/Modbus RS232/SDI-12/Modbus RS232/SDI-12
    Communications — Software SonTek-SL: Intelligent Flow SonTek-SL: Intelligent Flow ViewArgonaut
    Communications — Analog Output Option Integrated on Flow Display Integrated on Flow Display Separate AO module
    Communications — Flow Display Type SonTek Flow Display SonTek Flow Display N/A

    Actual maximum range depends on environmental conditions.
    ••Beam width reported at half power level (-3dB).
    Side lobe suppression improves the aspect ratio of the instrument enabling greater measurement range in shallower water.
     FS = Full Scale.
    § Power consumption will be higher if Flow Display is enabled.

  • Accessories

    SL500 Mounting Plate

    Mounting Plate

    SL500 Communication Cable

    Communication Cable

    SonTek Locking Sleeve

    Locking Sleeve

    SonTek Battery Pack

    Battery Pack

    SonTek Power Cord Kit (International)

    Power cord kit (Internationa

    SonTek US Power Cord

    US Power Cord

    SonTek Power Supply

    Power supply, 15VDC, 40W

    SL Series Splitter Cable

    Splitter Cable

    SL/IQ Series Communication Cable

    Communication Cable

    SL/IQ Series Battery Hook-Up Cable

    Battery Hook-Up Cable

    SL Series Mounting Plate

    Mounting Plate

  • Software

    SonTek-SL Software - V 3.0

    For SonTek-SL1500 (3G) and SonTek-SL3000 (3G) models only. The SonTek-SL Intelligent Flow software is an all-in-one package for interfacing with the 3G models of the SonTek-SL. Interface with the system, do setup, prepare deployment templates, run diagnostics, download data, create graphs and export data, all from the same intuitive software screen.

    Flowpack Software - V 1.21

    Become an instant velocity-indexing pro! FlowPack allows you to generate easy to interpret Velocity-Index ratings. Promising to make your data reporting process a whole lot friendlier (and faster), FlowPack also provides a simple method to store flow, velocity, and stage measurements — all through one software program. FlowPack can produce comprehensive reports that assist you in making better, more informed decisions.

    View Argonaut Software - V 3.72

    ViewArgonaut is a Windows-based deployment, postprocessing, and diagnostic software program that can be used with any SonTek Argonaut current meter (MD, SW, XR, Argonaut-ADV and SonTek-SL500).

    SonTek-SL 3G Firmware - V 3.100

    Find the latest version of SonTek-SL 3G Firmware here. Please contact for technical help or questions.

    Argonaut-SL/SW/XR Firmware - V 12.2

    Recent update corrects Modbus Output "Level" Parameter: The Modbus output of the "Level"parameter in Register 30051 & 30052 was corrected to not include the SystemElevation used in the "Stage" parameter and the flow calculations. It is now simply the water level above thevertical beam as intended. The changedoes not affect any other output formats (i.e. SDI-12) or internally recorded data.

    Previous udpates include:

    • Adds two new Channel Types (Culvert and Equation)
    • Improved Total Volume calculations; allows accumulating volume even when collection is temporarily interrupted
    • Option added to disable Total Volume Reset on the Flow Display
    • Adds SDI-12 Auto Sampling, which allows instrument to continue data collection even when no data logger command is received
    • Improved low-battery recovery; allows automatic data collection restart if a low-voltage battery recovers (e.g., when battery recharges itself via a solar panel)
    • Adds an alternate method of interrupting data collection via a modem using plus (+) or equals (=) characters
    • Scaling of analog output signals now based on setting of Total Volume units

    If you wish to take advantage of the new features in this version, follow the instructions below based on the version of firmware currently in your system.

    Argonaut SL/SW/XR Firmware Version 7.0 or Later

    This is a free update for systems that currently have v7.0 or later firmware installed. We strongly recommend updating your system to this new version. To update your system to this version:

    • Download and install the latest version of SonUtils - v4.20 (or later) for Windows 7/Vista/XP/2K, or v2.50a for Windows 98/95
    • Download and install the latest version of the ViewArgonaut Software program (v3.62 or later).
    • Download the Argonaut SL/SW/XR Firmware v12.0 Update Package - This package includes release notes that explain the new features and how to take advantage of them. It also includes the firmware file, your serial number access code, and instructions for loading the firmware into your system.

    Argonaut SL/SW/XR Firmware Versions Before 7.0

    Any system with a firmware version before v7.0 would need to be returned to SonTek for a hardware upgrade. There is a fee for the hardware upgrade service. Please contact our Support team for an RMA to upgrade your systems.

    Contact Support

    Argonaut-MD/SL/XR DOS Suite - V 5.91

    Argonaut-MD/SL/XR DOS-based programs used to control operation and to access data.

    *Note: Not for use with Argonaut-ADVs.

    Get the Software

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