An Overview of the Logging of Temperature Data

Knowing the temperature at which a product was exposed and for how long is critical in many businesses. When sterilizing surgical instruments or medical devices in an autoclave or heating food prior to canning, there should be evidence of temperature and time. Temperature monitoring helps facility managers prevent legionella, while environmental scientists use water temperature to assess the health of rivers and streams.. Monitoring these and other similar processes with temperature data loggers can provide evidence for verification.
The fundamentals of temperature data loggers are discussed here.
This type of data logger is specifically designed or built to work with temperature sensors, such as temperature probes (and in the case of a humidity and temperature logger, with humidity sensors too). a data logger is a device that can record multiple measurements at the same time. Typically powered by batteries, it takes data from one or more sensors and samples and records it at a predetermined frequency. Loggers are brought back to a PC for analysis at the end of the acquisition period. It is possible to send data from a data recorder directly to a computer or other device, eliminating the need to travel to the field.
All kinds of temperature data loggers are out there.
In order to record temperature data, the temperature sensor or sensors must be connected to an appropriate recording device that samples the sensor at predetermined times and records the data. Depending on where the sensor is placed, it can either be connected directly to the recording system or placed at a distance.
An in-built sensor
Combining a thermistor or thermocouple with a logger in a single container results in a small, lightweight recording device. The problem with this design is that it necessitates placement near a thermometer in order to be accurate. Internal sensor loggers cannot be used in high-temperature environments because their electronic components must operate within a specified temperature range. In the case of shipping artwork or perishable goods like eggs requiring temperature documentation, they can be useful.
By using a thermocouple.
Thermocouples are commonly used as direct inputs into temperature recorders. As an example, OMEGA’s HH1384 is a four-channel thermometer and data logger that can accept thermocouples of any type. It’s a workaround for temperatures that aren’t too high or low for the thermocouple data recorder, but it’s not a good solution for extremes in either direction. Many of them are small devices that can be used for a short period of time to record audio. Several general-purpose data recorders have inputs for thermocouple and thermistor, allowing them to be used as thermometers.
In cases where an external probe is used, it is necessary to calibrate it
It is possible to take measurements in extremely hot or cold conditions using a temperature data logger with a flexible probe (OMega’s OM-CP-HITEMP140-FP is an example). This allows the recorder to remain in one place while the sensor is moved to another location. As an example, the logger could keep track of temperature in an oven even if it was destroyed.
Thermometers with multiple temperature sensors
General-purpose and temperature data recorders with 32 inputs (one-ended, 16 differential) are available. Temperature sensors, including thermistors and thermocouples, can all be used with them.
A USB drive with an inbuilt sensor can be used to download data from a data recorder by plugging it into the USB port on a computer. In order to use other loggers, you’ll need a different cable, which is USB. Connecting the logger via Bluetooth® to your PC or mobile device is yet another option you have. There are two types of data loggers: those that communicate wirelessly with a central PC, and those that communicate over an Ethernet network. By using either of these approaches, the data is no longer stored on site at a data logger.

Applications

To ensure that sterilization procedures are done correctly and rivers and streams are not polluted, temperature measurement is essential. Measurements over a long period of time are necessary in some cases in order to determine long-term trends. Others want to know how high or low the temperature was, as well as how long they were exposed to it.
Temperature and humidity data collection
When performing temperature-sensitive operations or precise measurements, a history of temperature and humidity variation can be extremely helpful in identifying inefficiencies in facility management. Similar principles govern the propagation of plants and animals. A facility manager’s primary concern is protecting against legionella, a potentially lethal form of pneumonia. Data recorders that monitor temperature and humidity can be used in applications like this to provide a time-stamped record.

Another situation where a time-stamped record is useful is when artworks are transported. Logging at high temperatures can be dangerous, and knowing that your situation is being monitored may be enough to motivate you to take additional precautions.
“High temperature” is not defined, but a device that can withstand temperatures above 80°C (176F) is commonly referred to as “high-temperature” logs. High-temperature settings include autoclaves, pasteurization, and food and material processing. Food canning is a good example. There must be proof that the product has reached the minimum temperature required to kill pathogens like botulism. A probe is often included in loggers designed for these kinds of situations in order to keep the electronics safe from the heat.
monitoring of water’s temperature
In order to keep their fish healthy, aquariums use water temperature monitoring to ensure that their water is within a certain range. The temperature of rivers and streams is used by scientists in a similar manner to gauge the health of ecosystems. Data loggers can be used for a variety of purposes, but each has a different impact on the device.
In an aquarium, the logger can be easily accessed and the data can be recovered via a direct PC connection or Bluetooth. This reduces the need for a large memory capacity. The logger may have to be left in place for several months in order to collect good data on river temperatures. In such circumstances, factors such as memory size, battery life, and even wireless connectivity become more critical.
Custody Traceability
Many foods and medicines must be shipped under strict conditions in order to avoid deterioration. A small temperature data recorder can be incorporated into the items being carried to keep track of the conditions. Product integrity can be ensured and documentation provided in the event of a mishandling claim.
Steps to follow in the future

With so many options, finding the right temperature data recorder can be difficult. In order to identify and narrow down your options, you must first understand why temperature logs are necessary. OMEGA Engineering provides an online Data Logger Product Finder tool, but if you still have questions, OMEGA’s technical staff can assist you in finding the right equipment for your specific application.