In a multi-room agri-food plant, temperature and humidity control takes place in many locations at once: cutting rooms, freezing tunnels, dryers and finished product chambers. Each with its range, its working rhythm and its conditions. Whether it is a meat, dairy, canning or prepared meals plant, the problem is the same. This article explains how that cold chain is monitored with industrial IoT, based on a real deployment of Nebula ColdChain in a meat plant in Castilla y León.
The starting point
The quality department needed to continuously monitor the cold chain, automatically record data (data logging) and have a reliable alarm system, with temperature and humidity measurement in dryers.
The previous solution, based on standard RPi boards with custom HAT and WiFi, presented the typical problems of this type of environment: system instability, board lockups, coverage failures, difficulty with remote updates and, above all, an alarm system that did not work consistently and flooded the email with unreliable alerts.
An environment that makes it difficult for technology
The plant is located in the basement of a building, with limited 4G coverage although with telephone coverage, which affects the design of the communication network.
The environment combines high humidity, very cold and fluctuating temperatures (thawing), condensation, intensive cleaning with pressurised water and bleach, air currents, large thermal gradients within chambers and tunnels, vibrations and panels that hinder WiFi connectivity.
The technical challenge is to ensure continuous control of temperature and humidity in 17 rooms (3 of them dryers), with a robust, precise, scalable and maintainable system in the long term.
Nebula ColdChain is designed with criteria of robustness, precision and auditable historical record, reusable as a model in other regulated cold chain environments (slaughterhouses, canneries, dairy or pharmaceutical industry), where reliable records, traceability, audit capability and historical access to the data are required.
The IoT solution: Nebula ColdChain
Celestia TST has deployed an IoT architecture based on LoRa/LoRaWAN, with a single base station and a network of distributed sensor nodes in corridors and chambers, with wired external probes and enclosures designed for low temperatures, condensation and aggressive cleaning. The electronics are installed in the corridor and the probe inside the chamber, maximising autonomy and signal quality.
The sensors used are certified according to EN 12830, measure accurately over wide ranges (from drying conditions to deep freezing) and offer several years of autonomy depending on the transmission cadence. In this deployment, the cadence is 5 minutes, providing high-resolution monitoring while reducing the need for maintenance and associated downtime.
A detail of architecture makes the difference: the data model separates the control point from the physical sensor that measures it, so that the history is linked to the audited equipment and not to the specific hardware installed at any given time. The sensor is changed and the traceability remains intact, a key aspect for the defence against APPCC/HACCP audits.
Why LoRaWAN
The reliability of the entire system starts with communication. Nebula ColdChain relies on LoRaWAN, a long-range, low-power radio technology especially suited for demanding industrial environments. Compared to the WiFi connectivity of the previous system, LoRaWAN offers robust and noise-resistant communication, with great penetration in infrastructures: it passes through warehouses, partitions, panels and metal structures, and even reaches the interior of refrigeration chambers and freezing tunnels, where other technologies lose coverage.
Its low power consumption provides a decisive operational advantage: it allows for a quick and simple installation (wireless, without cables or construction) with several years of autonomy. Typically, a single base station covers the entire plant, with the option to operate on a network independent of the client's. The result is a stable network that eliminates the cuts and blockages that previously affected data capture.
If you want to delve into this technology, you can read the article What is industrial LoRaWAN?.
Data and alarm platform
Nebula ColdChain (cloud or on-premise) collects, processes and stores the data, with continuous backup in multiple locations and high availability. The platform offers real-time display screens by room, 24/7 time series queries and management of configurable alarms.
The logic of alarm works with sustained thresholds over time (not instantaneous), so that normal peaks of defrost cycles are not treated as failures, avoiding the false alarms that saturated the previous system. The alarms allow for different levels of severity: an initial out-of-range warning, an escalation when the incident does not recover after a certain time, and a specific warning of lack of data. Notifications are sent by email, with the possibility of SMS or push notification to mobile according to configuration.
Nebula ColdChain generates inspection-ready reports (both for data queries by equipment and period as well as incidents), allows for recording the cause and the solution of each alarm as a minor non-conformity, and includes optional API integration with the client's systems (ERP, MES, LIMS, Power BI). The data is always the property of the client and can be exported in CSV.
End-to-end project and role of Celestia TST
Celestia TST acts as end-to-end technology partner: defines the architecture, carries out the detailed engineering, designs the installation, configures hardware and software, launches the solution, verifies the coverage on-site and trains the client's team.
This integral approach facilitates that the quality, operations, and management teams obtain value from the data without needing to be experts in IoT, aligning with the proposal of Celestia TST to accompany the client throughout the project cycle, from the idea to operation.
Value from day one
From the start, the quality team has continuous and verifiable data, with information where it is needed. The operational result has been a tool valued as practical and reliable, which replaces untrustworthy alerts with objective monitoring of the plant.
A benefit observed from the first days is the objective verification of repairs and the early detection of faults. When a refrigeration technician intervenes on a cooling unit, the quality team no longer relies on their word: by comparing the behaviour of the unit before and after directly in the history, it checks whether the repair has been effective or if the unit continues to behave the same.
In a real case, after some minor repairs announced by the technical service, it was enough to connect to the system to confirm that the behaviour of the unit had not changed and that the intervention had not resolved the problem. Monitoring thus ceases to be merely a record for compliance and becomes a tool for maintenance supervision and operational decision-making.
In the medium term, the continuity of the cold chain and the reduction of waste rely on the ability to anticipate deviations before they become a problem. And maintenance costs decrease thanks to a robust LoRa network, long-lasting sensors, and a design intended for an aggressive environment, which reduces operational incidents compared to the previous solution.
Application to other cold sectors
This deployment is a meat plant, but the architecture of Nebula ColdChain monitors refrigeration chambers, freezing tunnels, dryers, processing rooms, and finished product warehouses in any agri-food plant. In pharmaceuticals, the same approach is adapted to vaccine chambers, preparation areas, and cold logistics, with the redundancies and validations required by applicable regulation.
Key questions about the IoT solution for cold chain
With a network of wireless sensors that measure temperature and humidity in each chamber, tunnel, or dryer and continuously send the data to a central platform. There, they are automatically recorded, visualised by room in real time, and alarms are generated when a value goes out of range long enough to be considered a real failure.
WiFi loses coverage inside refrigeration chambers, tunnels, and buildings with metal structures, and requires constant wiring and maintenance. LoRaWAN is a long-range and low-power radio that penetrates walls and panels, reaches the interior of the chambers, and allows years of autonomy per sensor. A single base station usually covers the entire plant.
Yes. It generates an auditable history and reports ready for inspection by team and period, allows recording the cause and solution of each incident as a non-conformity, and maintains traceability even if a sensor is changed, because the data is linked to the control point, not the hardware.
The alarm logic works with thresholds sustained over time, not with instantaneous readings. A normal peak from a defrost does not trigger a notification; it is only reported when the deviation is maintained. Additionally, there are levels of severity and a specific notification for lack of data.
Yes. They are certified according to EN 12830 and measure accurately from drying conditions to deep freezing, with housings and probes designed for condensation, aggressive cleaning, and large thermal gradients.
Yes, via an optional API with ERP, MES, LIMS, or Power BI. The data is always the property of the client and can be exported in CSV.
No. The same architecture monitors refrigeration chambers, freezing tunnels, dryers, and finished product warehouses in any agri-food plant, and adapts to pharmaceuticals with the validations required by their regulation.
Do you need to monitor your cold chain?
Nebula ColdChain is the IoT solution for the cold chain from Celestia TST: continuous logging, reliable alarms, and auditable history. Contact us and we will help you define where to start.
Written by Ana Escalante Galán, Head of Marketing and Communications at Celestia TST
Technical review by Iván Bermejo, Head of IoT Industry Business Development