Designed to accurately monitor the temperature of mission critical refrigeration units, ensuring that the contents remain at the critical temperature required for your application. The ISL124G is battery powered, wireless and simple to install at any location.


  • External temperature probe

  • Battery powered

  • Wall bracket mounting options

  • Temperature alarm threshold hysteresis

  • Temperature Edge Intelligence (thresholds – warning, alarm)

  • Available as a ‘data as a service’ offering

  • Configurable transmit interval for each mode (standard, warning and alarm)
  • Configured over the air from ISL LoRa™ USB dongle
124G - 45 Deg


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Long Battery Life

Our sensors have been designed to have a battery life of up to 10 years, so you don't have to worry about changing them frequently.


Reduce Costs

Identify problems before damage occurs to stop waste, prevent costly site shutdowns and reduce your fuel consumption. 


A Proven Partner

At Invisible Systems, we've worked in IoT for over 17 years. Our solutions have a proven track record in supporting businesses. 

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Real-Time Online

Together with Real-time Online, the sensors enable constant monitoring, deliver pro-active alerts on threshold breaches and generate bespoke reports


Reduce Carbon Emissions

Our products have been proven to reduce carbon emissions by as much as 83% on some construction sites

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Easy to Install

Choosing wireless sensors and a cloud platform enables you to reduce your installation and maintenance costs.



Configurable high/low thresholds allow different transmit intervals when thresholds are crossed providing advanced edge intelligence to the network, and enable alarms to be generated by Realtime-Online™.


Data from every sensor in your network is reported back through Invisible Systems Big Data architecture either to our Monitoring and Analytics platform Realtime-Online™, or to a partner cloud platform via our API, ensuring that your data is visible, actionable and valuable to your organisation.


The 124G transmitter connects to the cloud via Invisible Systems cellular LoRa™ gateways, providing low power, reliable communication and long battery life. Invisible Systems can provide their in-house built Realtime-Online™ cloud portal to make this an ideal low-cost end-to-end solution.


The ISL124G is a LoRaWAN certified device and Invisible Systems are members of the LoRa alliance. It offers both ABP and OTAA activation options and is designed to work with all LoRaWAN gateways and network servers.




Frequency/Band (LoRa): EU 868Mhz Other regions available on request

Frequency/Band (LoRaWAN): EU863-870 Other regions available on request

Expected range (line of sight): Up to 10km

Power: LoRaWAN 25mW (14 dBm) LoRa: 100mW (20 dBm)


Approvals: CE, FCC, IC, Other regions available on request

FCC ID: Contains module VPYCMABZ

ICID: Contains module 722C-CMABZ


Dimensions (mm): 70x70x24 (excl bracket)

Enclosure colour: White

Enclosure plastic type: ABS

Operating Temp Range: -20°C to +60°C

Operating Humidity Range: 30% RH to 90% RH

Battery: 1 x AA (2400 mAh)

Batteries type: Lithium Thionyl Chloride (Non rechargeable)

Expected battery life, 6 min Tx interval: Up to 1.8 years

Expected battery life, 6 hour Tx interval: Up to 10 years

Operating lifetime: Up to 10 years

Power type: Battery 3.6VDC


Measurement interval range: 10 secs - 60 mins

Tx interval range (multiple of measure intervals): 1 min - 6 hours



Measurement Range: -20°C to +60°C

Accuracy: ±0.25°C (typical) from -40°C to +125°C
±0.5°C (maximum) from -20°C to +100°C
±1°C (maximum) from -40°C to +125°C

Resolution/Step-size: 0.1°C

Drift: < 0.05 oC over lifetime

Sensor characteristics: Digital

Calibration: Optional

Probe: 1m PVC Ribbon with 7mm diameter stainless
steel pocket probe



Door contact: 1 x external magnetic switch contact

Cable: 1m PVC Ribbon

Download Datasheet