A cold chain data logger otherwise referred to as a temperature data logger, is a device that records and logs ambient temperature and other data at set intervals over a period of time. They should be compact, relatively inexpensive, and should be able to work reliably without any major infrastructure like data cable networks or fixed temperature probes.
Temperature loggers are growing in popularity, and they’re widely used by businesses in industries where monitoring indoor environmental conditions, adjusting storage temperature and controlling ambient conditions are essential — particularly when it comes to the storage of food or pharmaceutical products. Battery-powered portable data loggers are growing in popularity as well, particularly because they’re an ideal solution to track and manage cold chain shipments in transit.
The best temperature data loggers have most (or all) of the following features, some of which are non-negotiable for optimum cold chain monitoring and management:
- Continuous temperature monitoring.
- Detailed time-stamped temperature logs.
- Temperature excursion indicator (visual or via alerts).
- Reliable storage and transfer of temperature data (internal memory, removable storage units, or cloud storage).
- Easy data accessibility (through computers or smart devices).
- Software or applications for reporting and analytics (either local installations or web-based systems).
- Systems that are easy to set up, deploy, and use.
While there is a wide variety of cold chain data loggers with a myriad of features to suit every conceivable need, most fall into one or more of these three buckets:
- Basic temperature data loggers — Stand-alone devices that are low-cost, easy to set up and quick to deploy. These may or may not be battery powered, and generally record just temperature data on an internal memory storage unit over time.
- Multi-sensor temperature monitors — Data loggers that record additional ambient condition information such as relative humidity, pressure, the concentration of certain gases, etc. They’re complex devices that sometimes need to be constantly plugged in to a power source, and they can store information internally or offload it to a central data server or cloud storage systems for later processing and analytics.
- Enterprise-level temperature monitoring systems — Depending on specific needs, these systems consist of one or more types of temperature or ambient condition sensors, they’re integrated with larger enterprise information systems like warehouse management systems or cold chain shipment monitoring systems, and they also have features like live alerts, predictive analytics, and can integrate or scale as required to support large organizations and their operations.
With so many choices available today, it’s undoubtedly challenging to pick one that’s perfect for your needs. Whether you need a temperature logging system for a cold chain warehouse or you need a temperature tracking system with live alerts to monitor temperature-sensitive shipments in transit, the final choice usually depends on answers to the following questions:
- Do you have to measure a single parameter, or do we need to track a range of conditions?
- How long do you need to measure them?
- Do you need alerts when conditions exceed acceptable thresholds?
- How often do you need to measure temperature or condition data?
- How often do you need to view or transfer that data?
- Where do you need to view or manage the data; is it a computer, mobile device, or an online system?
- Does the data logger need to be waterproof or work in harsh environments?
- Do you need to set up and deploy the system yourself?
- Will you need additional software, data plans, or systems to handle and analyze the data?
The answers to these will outline your specific needs.
Armed with that, you should have an easier time evaluating and comparing the cold chain data logger options available to you.
Whether you’ve used temperature loggers before or you’re just getting started, here are some of the most important features to look out for while evaluating the best temperature data loggers.
1 — Suitable Accuracy
Accuracy specifications vary widely among different types of data loggers depending on their purpose.
Cold chain data loggers meant for use in the pharmaceutical space, for instance, can measure a greater range of temperatures, and they can measure those temperatures accurately to within a degree. Their counterparts, data loggers developed for use in the food industry for example, may not be able to measure the same range of temperatures, and they’re accurate to within a few degrees.
Needless to say, there are differences in how they’re built — and billed — so understanding your specific requirements for accuracy and room for error will help you avoid paying for levels of data accuracy you may not need.
2 — Multiple Sensors
More advanced cold chain data loggers don’t stop at measuring a single parameter like temperature.
They also have sensors to measure and log additional information like humidity, light, physical shock, air pressure, the concentration of specific gases, and many more. The additional information is vital when monitoring certain cold chain shipments like vaccine vials, chemicals, or other temperature-sensitive items that require special care and handling.
The best temperature loggers have these sensors in-built, or they allow you to connect additional sensors to suit your needs.
3 — Variable Sampling Frequency
Most temperature loggers are portable battery-powered devices. The more often they measure and record temperature data, the faster these batteries run out.
Needless to say, if you need to record data frequently, and you need to do so using multiple sensors, it’s important that you can adjust your cold chain data logger’s recording intervals to suit your needs while still making the most of its battery backup.
You can, for example, set the recording interval to 5 seconds or less if you’re using the data logger to track temperature-sensitive pharmaceutical shipments, or you could set the interval to 30 minutes or more for food shipments.
It’d also help if you can configure the temperature recording intervals remotely as well.
If the temperature of your shipment or stored goods spiked and then leveled off, it’s important to maintain the low temperature as far as possible to avoid further damage and risk. In such cases, it helps if you can increase the number of readings taken to make sure that there are no more temperature spikes which could lead to irreparable damage.
4 — Long Battery Life
Modern portable battery-powered temperature data loggers are extremely low-power devices. The use of multiple sensors or logging information at faster rates can still put these low-power devices through their paces, however. Although the latest generation of cold chain data loggers (like Bluetooth temperature data loggers) have batteries that can last a year or more, make sure they’ve got the capacity to meet your specific needs without running out of juice.
5 — Sufficient Data Storage
Most portable cold chain data loggers are built for lengthy deployments, either to track shipments over a course of days or to track warehouse and storage conditions over a course of a few months.
Either way, the temperature loggers build up a stockpile of data.
Depending on the length of its deployment and the type of data storage and transfer your data logger supports, you’ll need to assess your device’s storage needs.
Data loggers that store information locally needs to be accessed frequently to extract the information on them via USB, an SD card, or using Bluetooth or WiFi to transfer data to a portable device like a laptop or smartphone. In the off chance, you aren’t able to retrieve records in time, there’s a risk they’ll be overwritten by newer logs as time goes by. While that’s unlikely, since most low-cost cold chain data loggers can store upwards of 10,000 temperature measurements, it’s always better to have some buffer to work with.
Make sure your logger has enough memory to support long deployments and fewer site visits.
Better yet, opt for one with inbuilt data connectivity and cloud storage so your information is constantly backed-up online for later retrieval. Such hybrid temperature loggers can buffer readings when there’s no connectivity and then stream the stored temperature readings when they’re connected to a network, which could be cellular, WiFi, or even a mobile hotspot.
Whatever your setup, ensure that you’re capturing every bit of data your logger gathers so your temperature trails stay unbroken.
6 — Ease & Speed of Data Transfer
Speaking of capturing every bit of data, how you access the stored readings on a temperature data logger is also an important feature to consider.
Most standalone data loggers use onboard storage, which is accessible either as a removable SD memory card or through a USB interface.
In most cases, however, it’s not practical to bring and use a computer at a cold storage facility, and neither is it easy to collect data loggers and bring them back to an office – especially if you’re handling hundreds of devices every day. Retrieving the data through such manual processes is not just cumbersome, it’s also time-consuming.
In an effort to simplify and speed up the data collection process, wireless technologies like WiFi and Bluetooth Low Energy (BLE) were applied to data loggers, allowing them to transmit data wirelessly to mobile devices or a receiving station that could be anywhere between 50 to 100 feet of the device.
Such wireless data capture systems are particularly useful when you need to read several devices in batches or situations where temperature data loggers need to be deployed in hard-to-reach spaces within a facility.
Systems, where alerts generated by a wireless data logger go out over the Internet, can also be your first line of defense against cold chain interruption. When used in tandem with a mobile access point, wireless data loggers can track the temperature of shipments in transit as they’re happening. Connected data loggers allow you to act on the data instead of just logging it. The information can be automatically forwarded to stakeholders in the field that need to take action, which gives you them enough of an early warning to intervene and contain the damage as soon as temperature excursions begin to occur.
For speedy hassle-free operations, always insist on wireless cold chain data loggers.
7 — Ease of Installation & Use
Time is money, so make sure that data logger installation and set up is easy.
Most cold chain data loggers are easy to deploy and operate, they can also work independently of a computer or other device. Shipping temperature loggers come pre-programmed; all you need to do is push a button to start or stop the logging process. Some wireless data loggers don’t need any dedicated equipment beyond a smartphone or tablet to configure the logger and download data from it through an app, saving both time and money.
Wireless sensor networks that work with WiFi or a standalone cellular data connection can also transmit accurate live temperature monitoring data from dozens of points to a central server or the cloud, for more efficient aggregation and processing.
That’s another advantage of wireless temperature data loggers — there’s no need to install wiring throughout a warehouse or hook up sensors to a truck or shipping container. What’s more, the chore of manually retrieving data from individual data loggers is no longer necessary, freeing up labor that can be used elsewhere.
8 — Reporting & Analytics
Besides easy data transfer and sharing, also look for features that help save time while analyzing data.
Some temperature loggers continuously display the maximum, minimum, average, or mean kinetic temperature (MKT); others simply log the data and indicate a temperature excursion using an LED light as an external cue that temperatures spiked. Even simple systems like these eliminate the need to connect the logger to a computer or download data to a handheld device, you can tell what cold chain goods are damaged or not at a glance.
Wireless temperature data loggers, on the other hand, enable real-time remote access to temperature and other types of data via cellular, Wi-Fi, or other communication systems. Data can be easily streamed to or accessed from a secure web server or integrated into with ERPs, TMSs, WMSs, or any enterprise software systems relatively easily.
The ability to integrate live cold chain data with cloud-based data storage and analytics solutions also give you the Big Data advantage; you can track patterns and use past events too, for example, predict how much coolant you’d need for a multimodal shipment, or where hotspots are likely to develop in fixed storage areas.
9 — Flexibility
A huge advantage of using temperature data loggers — especially wireless ones — is that you can deploy them anywhere you need to. When evaluating temperature loggers, make sure they give you the same accurate and reliable performance you expect in a range of environments — indoors, outdoors, or in-transit.
With no need for wiring or installation, easy data access through connections like WiFi, cellular networks or Bluetooth, and long-lasting batteries for long-term deployments, wireless data loggers will, of course, be your best option.
The Final Five
No matter what other features you’d like to have in your final choice, make sure your temperature data logger has:
- Reliably and secure temperature data storage — make sure the onboard memory and battery backup are top-notch.
- Easy control over the recording process — either manual start/stop buttons or an easy to use mobile app.
- Wireless data transfer — to reduce investment and effort in installation and data capture.
- Live temperature trails — and excursion alerts.
- Predictive analytics — or at the very least, MKT on the move.
Be sure that your live temperature tracking solution (or solution provider) has the knowledge and expertise to best meet your specific needs, both now and in the future.
This article was first published on Roambee on 20 December 2018 with permission to share from the writer.