R2 Gauge – Large-range connected crack monitor

539,00 w/o VAT

  • Autonomous connected crack monitor with cabled external large-range sensor (100 mm), ideal for monitoring wide-opening cracks. (Compact version: R1 crack monitor)
  • Includes 3 sensors: Linear displacement – 0.01 mm resolution, Temperature – 0.1°C resolution, Relative humidity – 1% RH resolution
  • 1-year subscription included for automatic data transmission (annual renewal: €49 excl. VAT).
  • Remote configuration and monitoring from a PC or smartphone
  • Management of a Monitoring+ mode
  • Up to 8 years of battery life

Made in France Made in France

Technical specifications

  • Linear sensor
    Resolution: 0.01 mm, Measurement range: ~100 mm, Accuracy: ±0.1% FS
  • Temperature sensor
    Resolution: 0.1°C, Measurement range: −40°C to 125°C, Accuracy: ±0.2°C
  • Humidity sensor
    Resolution: 1% RH, Measurement range: 0–100% RH, Accuracy: ±2% RH
  • Measurement frequency
    Configurable in the app: 1h, 2h, 4h, 6h, 8h, 12h, 24h
  • Data transmission frequency
    Configurable in the app: every 12h, daily, every 2 days, every 3 days, weekly
  • Battery life
    Between 2 and 8 years depending on measurement and transmission settings
  • Operating temperature
    From −30°C to +70°C
  • Network coverage
    LTE-M / NB-IoT multi-operator communication module. Works in basements / underground areas / parking facilities.
  • Mounting
    Mounting on solid or hollow substrates using the supplied hardware. Angled mounting possible with the mounting kit.
  • Dimensions
    Housing: 84 × 84 × 56 mm – Sensor (retracted): 250 mm × Ø20 mm
  • Ingress protection
    Housing: IP66, Sensor: IP65
  • Weight
    350 g including the battery
  • Warranty
    2 years

R2 Gauge – Large-range connected crack monitor with cabled external linear sensor

The R2 gauge is a connected crack monitor designed to measure large crack movements, up to 100 mm.
Thanks to its linear sensor external to the housing and connected via a cable (approx. 1 m), it is ideally suited to structures where crack opening variations can be significant—applications where the R1 gauge (23 mm range) reaches its limits.

The R2 gauge builds on the proven principles of Saugnac connected sensors, while extending the range of applications to contexts involving greater structural deformation.

✔️Key points

  • Cabled external linear sensor – 100 mm range
    Ideal for wide cracks or significant movements on concrete, masonry, etc.
  • Integrated humidity and temperature sensors to correlate changes with ambient conditions.
  • Web and mobile application with unrestricted access, to view data remotely and in real time.
  • One-year subscription included (activated upon first commissioning).
    Data remain available in the app even after the subscription expires.
  • Mounting hardware supplied for solid or hollow substrates.
  • Reusable gauge after data archiving.
  • Multi-operator connectivity ensuring reliable communication via the best available local network.
  • Battery life up to 8 years, depending on measurement and transmission frequency.
  • Remote configuration via the app to adjust parameters to monitoring needs.

🌐Remote crack monitoring with the app

All information from the three sensors—displacement, temperature and humidity—can be viewed via the app https://saugnac.app on both smartphone and computer.
Access to this app is completely free, as for all our measuring instruments. Even after the data transmission subscription expires, your account and measurement history remain available.

The interface makes it possible to display customizable graphs, downloadable as image files for easy integration into your reports.
Raw data can also be exported to Excel or CSV files for additional analysis.

A shareable link can be generated to provide access to a dynamic report, always up to date at the time it is viewed.

Finally, the app includes a system of configurable alerts: you can set a threshold up or down relative to the first measurement. If exceeded, an email notification is automatically sent.

To test the app with the demo account, use the following credentials:
– user: saugnac.en@gmail.com,
– password: demo

🚨“Monitoring+” mode: enhanced monitoring activated remotely

During exceptional events (works, impacts, unusual movements, structural alert), the R2 gauge can be switched to “Monitoring+” mode, activated remotely.
This mode increases the measurement and transmission frequency for closer, more responsive monitoring.

The configurable parameters are:

  • Measurement frequency: every 2, 5, 10, 20 or 30 minutes
  • Transmission frequency: every 1, 2, 3 or 4 hours

Once the maximum duration is reached, standard mode automatically resumes to preserve battery life and data volume.
“Monitoring+” can be reactivated several times for specific monitoring campaigns, up to 12,000 measurements.

Measurement frequency Max. duration
2 min 4 days
5 min 10 days
10 min 20 days
20 min 40 days
30 min 60 days

Quick installation and commissioning of the R2 gauge

The R2 gauge has been designed for a simple, intuitive installation, achievable without any specific technical knowledge.

With the supplied mounting hardware and the Saugnac app (accessible on smartphone or computer), commissioning takes only a few minutes.
An illustrated manual is supplied with each device to guide the user step by step.

1. Registering the gauge in the app

Open the Saugnac app and add your R2 gauge by scanning the QR code on the housing or by manually entering the identifier printed underneath. The gauge then appears in your interface, ready to be configured.

2. Measurement settings

From the app, customize the settings according to your monitoring needs:

  • Time of the first measurement
  • Measurement frequency: every 1h, 2h, 4h, 6h, 8h, 12h or 24h
  • Data transmission frequency: every 12h, or every 1, 2, 3 or 7 days

💡 The more spaced out the transmissions, the longer the crack monitor battery life.

3. Powering on

Carefully open the housing and switch on the internal toggle.
The gauge automatically connects to the network and indicates correct operation via an LED indicator.
Once initialized, it goes into standby until the first scheduled measurement.

4. Mounting on the structure to be monitored

Position the linear sensor and mount the R2 gauge using the supplied components:

  • Solid substrate (concrete, stone): use the brass anchors
  • Hollow substrate (brick, cinder block, light partition): use the EPDM anchors

Mounting the connected crack monitor

The R2 gauge is supplied with 2 types of anchors:

Brass anchors for solid substrate for the R2 connected crack monitor
Brass anchors for solid substrates requiring Ø8 mm holes.
Required tools not supplied for mounting on solid substrates with brass anchors: drill, Ø8 mm drill bit, 5 mm hex key + 3 mm hex key to open the housing and power on the R2 gauge.
EPDM anchors for hollow substrate for the R2 connected crack monitor
EPDM anchors with nuts and washers for hollow substrates (also usable on solid substrates) requiring Ø13 mm holes.
Required tools not supplied for mounting on hollow (or solid) substrates with EPDM anchors: drill, Ø13 mm drill bit, to open the housing and power on the R2 gauge

📏Standard flat mounting

To mount the gauge, first mount the housing, then the sensor. Mounting is done easily using the supplied hardware. All operations are described step by step in the detailed manual.

Mounting the R2 connected crack monitor - step 1 Mounting the R2 connected crack monitor - step 2 Mounting the R2 connected crack monitor - step 3 Mounting the R2 connected crack monitor - step 4 Mounting the R2 connected crack monitor - step 5 Mounting the R2 connected crack monitor - step 6 Mounting the R2 connected crack monitor - step 7 Mounting the R2 connected crack monitor - step 8 Mounting the R2 connected crack monitor - step 9 Mounting the R2 connected crack monitor - step 10

📐Angled mounting or shear displacement monitoring

With the R2 mounting kit, angled mounting or shear displacement monitoring is possible.

R2 angled mounting kit - example 1 R2 angled mounting kit - example 2

Subscription and network coverage

The connected crack monitor includes a multi-operator subscription ensuring optimal coverage in all European countries and in the main countries worldwideFor any questions regarding coverage in your country, please do not hesitate to contact us.

As soon as it is powered on, the gauge automatically selects the network with the best signal quality, guaranteeing reliable and continuous data transmission, even in the most remote areas.

It uses LTE-M and NB-IoT protocols, designed specifically for industrial IoT devices. These technologies, based on operators’ 4G infrastructure, offer excellent connection stability, low power consumption and long range, ensuring long-term operation without communication interruptions.

The subscription included with the connected crack monitor is valid for one year.
After expiry, access to previously recorded data remains available, but new measurements are no longer transmitted until the subscription is renewed. Email notifications are automatically sent before the expiry date to inform the user.

Renewal can be completed directly from the app, either via secure credit card payment or via a purchase order generated from an automatic quotation. The annual subscription fee is €49 excl. VAT.

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