Sensus Ultra

Dive data recording at a fraction of the cost of a dive computer


Sensus Ultra is ReefNet's third-generation dive data logging device. Building on the strengths of its predecessors, it remains the simplest, most convenient tool for collecting detailed dive log data. Remarkably, it's also the most affordable!

Don't let Sensus Ultra's diminutive size (1" x 1.3" x 1.75") fool you. Packed inside are a sophisticated sensor, flash memory and processor capable of storing 1500 hours of dive data with a 10 second sampling interval.

Ready to use right out of the box, simply clip Sensus Ultra to your dive equipment and it will automatically record depth and temperature profiles for all your dives. Downloading your dive data takes just a couple of mouse clicks. It's really that simple!

Remarkable Precision

Dive computers typically record data with a resolution/accuracy* of 1 foot in depth and 1 degree in temperature (or worse). This is fine for recreational dive logging, but for technical diving or scientific purposes, it's rather coarse. Our users have been asking for more detail, and Sensus Ultra delivers! The resolution of the new Sensus Ultra is over 20 TIMES BETTER than that of the Sensus Pro:

  • Depth is resolved to better than 0.5 inches of water, with accuracy of +/- 1 ft
  • Temperature is resolved to 0.01 C (~ 0.02 F), with accuracy of +/- 0.8 C

In the scientific market, this increased resolution allows Sensus Ultra to compete very favorably with much more expensive depth/temperature monitoring devices.

*It's important to distinguish between resolution and accuracy. Resolution specifies the smallest change that can be detected, whereas accuracy specifies the "correctness" of the data.

Configurable Options

If all you want is a simple dive logger, Sensus Ultra's standard configuration will do just fine. But if you'd like more control over how your data are recorded you may configure a number of device parameters using our bundled software:

  • Sampling Interval - Default 10 seconds. Configurable from 1 second to over 18 hours. Example...a researcher might select 60 seconds, extending the capacity to ONE YEAR for long-term water temperature monitoring.
  • Activation Depth - Default 3 fsw. Configurable in mbar (absolute). Example...while diving at high-altitude, you may wish to reduce the activation pressure accordingly.
  • End-Timer - Default 15 samples. i.e. the number of continuous samples above the activation depth which signal the completion of a dive. Example...dive instructors could extend the timer to prevent brief ascents (talking with students) from terminating the dive record prematurely.
  • User Data Storage - Approximately 16 kB of storage in the recorder is reserved for your private use. You may store certification data, medical info, or any other data in this space, and it may (if you wish) be securely encrypted with a password!

By choosing the right combination of recording parameters, you can tailor the Sensus Ultra to suit the conditions or your particular style of diving.

Easy-to-Use Software

Sensus Manager software makes reviewing your dive profiles simple and convenient. Click below to take a tour, or download this FREE software right now!

Windows Mac OS 9 & X Palm OS
Windows Tour
Mac OS Tour
Palm OS Tour
Take a tour Take a tour Take a tour

Profile data from Sensus recorders can be quickly downloaded to ALL major computer platforms including Windows, Mac, Linux, Palm, Pocket PC, etc. (some supported only with third-party software). A universal download cradle makes connecting to any of these systems a breeze. The download process takes just a few seconds.

Dive Log Elements
Basic dive logging elements make Sensus Ultra a complete dive logging solution for recreational divers.

Common Applications

Although originally designed for recreational divers, ReefNet's Sensus line of data recorders has been used in a number of different applications across a wide spectrum of industries:

  • Recreational Divers - basic dive logging, dive computer backup, and emergency medical treatment
  • Commercial Divers - dive logging for OSHA requirements, personal use, and liability determination (in the event of accident)
  • Freedivers - detailed recording of training profiles
  • Dive Instructors - monitoring of students, review of student profiles for ascent rate analysis, liability determination (in the event of accident)
  • Scientists - DAN research programs, long-term tidal/temperature logging, backup/replacement for other instruments, animal tagging
  • Medical - logging of hyperbaric chamber treatments, for both tenders and patients
  • Other Industries - fishing net depth tracking

Technical Specifications

Feature Description
Activation Activates at a depth of 3 ft. Deactivates after about 3 minutes above 3 ft. Threshold and end-timer are user-configurable.
Sampling Interval 10 seconds. User-configurable from 1 s to over 18 hrs. Capacity changes with interval (e.g. 1500 hrs @ 10 s., 150 hrs @ 1 s.).
Capacity Approx. 1500 hours of data profiles (depth & temperature). Based on standard 10 second sample interval.
Working Limits Depth, 500 feet. Temperature, -20 C to +40C.
Units Software selectable view of meters or feet, and degrees C or F.
Downloading Via exposed metal pads on case. Mates with universal download unit. Downloads to desktop, laptop, or Palm computers for profile analysis and logging.
Case Material Glass fiber-reinforced polycarbonate. Black or Yellow.
Size 1" x 1.3" x 1.75 " with split ring for attachment to BC or other gear.
Lifetime Up to 10 yrs, permanent lithium cell.
Identification Individually serialized both physically and electronically. Allows tracking of several devices on one computer.
Options Custom engraving available.

Attention Third-Party Software Developers

Unlike other dive computer manufacturers, ReefNet realizes the benefits of publishing the technical details of its data recording devices. If you're a software developer, dive organization, or just curious, you may download our free Developer's Guides. In them we carefully detail everything you need to know to be able to download data from Sensus recorders. The Sensus Ultra Developer's Guide is AVAILABLE NOW!

You are both welcome and encouraged to create your own software that downloads or integrates data from our data recorders in any way you like. If you do, we'd love to hear from you, and if we think you've done a good job, we'll even tell all of our users about it!

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