S31-NB Frost Alarm — temperature and humidity
The sensor that calls you in the middle of the night when frost threatens, on up to 10 numbers. Installed in 5 minutes, no gateway.
195 € excl. VAT — recommended retail price No subscription
S31-CS solar Frost Alarm — temperature and humidity
The same frost alarm sensor as the S31-NB, with a built-in solar panel that recharges the battery every day. It calls you when frost threatens, on up to 10 numbers.
207 € excl. VAT — recommended retail price No subscription
What it solves
- Be called in time to start your protection (sprinklers, frost candles, air stirring)
- Track temperature, humidity and computed wet-bulb temperature every 15 minutes
- Forget battery swaps: the solar panel recharges the battery daily
User manual (PDF) All documentation
Included in the price
- ✓ SIM card preloaded for 3 to 5 years (350 Mo, 60 calls/SMS)
- ✓ Alerts by voice call (10 numbers), SMS and unlimited email
- ✓ Access to the Supervisor platform included
- ✓ Built-in solar panel + 3000 mAh battery
Technical specifications
- Measurement range -40 °C to +80 °C
- Accuracy ± 0.2 °C
- Relative humidity 0 to 100 %
- Wet-bulb temperature computed (measured as an option)
- Transmission multi-network GSM, every 15 min
- Power supply built-in solar panel + 3000 mAh battery
- Battery life without sun 20 to 40 days
- Ingress protection IP66
- Installation no gateway, no settings
The S31-CS is the solar version of the FURGO frost alarm sensor. Same mission as the S31-NB: measure temperature and humidity every 15 minutes, compute the wet-bulb temperature, and call you — by phone, on up to 10 numbers — as soon as your threshold is crossed. The difference lies in the power supply: a built-in solar panel recharges the battery every day, so there is no battery to replace.
Solar or battery: how to choose
The S31-CS carries a 3000 mAh battery recharged by its panel. With no sun at all, it lasts 20 to 40 days; the panel only needs around 2 hours of exposure a day to stay permanently charged. If the sensor has to live under dense foliage, in fruit growing for example, choose the S31-NB and its slow-discharge 8500 mAh battery instead. In open fields, in the vineyard or on a clear post, solar is the easy choice.
Nothing to install, nothing to pay each month
The sensor arrives with its SIM card activated and preloaded: you switch it on, it transmits. No gateway, no pairing, no mandatory app. Alert thresholds, the numbers to call and the reading history are managed from the platform, access included. The SIM plan covers 3 to 5 years of use; after that, a top-up of a few dozen euros is enough. It is not a subscription: without a top-up, nothing is charged to you, and the hardware remains yours.
Frequently asked questions
How is it different from the battery-powered S31-NB?
The S31-CS has a built-in solar panel that recharges its 3000 mAh battery every day. The S31-NB runs on a long-life 8500 mAh battery, with no panel — it is the one we recommend in fruit growing when sun exposure is not guaranteed.
What if there is no sun for several weeks?
The battery lasts 20 to 40 days without any solar recharge. In practice, 2 hours of sun a day on the panel is enough to keep it charged. The battery level can be monitored from the platform.
What happens when the SIM plan runs out?
After 3 to 5 years depending on use, you top up the plan — a few dozen euros, not a subscription. The sensor and the platform keep working.
Do I need an antenna or a gateway on the farm?
No. The sensor transmits directly over multi-network GSM, anywhere a phone gets signal. You switch it on, it transmits.
Going further This sensor answers the need “Frost alarm for orchards and vineyards” — read the full page (solution comparison, 5-year total cost, real cases).
