When you start a temperature logger, it does not instantly become the same temperature as the fridge, freezer, cool room or esky you have placed it in.
If the logger has been sitting on a desk, in your hand, or in a delivery area at room temperature, it will take a little while to cool down once it is placed into a cold environment. During that short period, the logger may record temperatures that are warmer than the actual storage area.
That is where a delayed start is useful.
A delayed start tells the logger to wait for a set amount of time before it begins recording.
For example, if you set a 5 minute start delay, the logger will not take its first reading until 5 minutes after you press the start button.
The logger has still been started. It is simply waiting before it begins logging temperature readings.
The most common reason to use a delayed start is to avoid false alarms at the beginning of a trip, test or monitoring period.
For example, imagine you are placing a LogTag into a freezer. The logger itself is at room temperature when you press start. Once you put it into the freezer, it may take 10-15 minutes for the body of the logger to cool below the upper alarm limit.
Without a delayed start, the logger may record those first few warmer readings and trigger an alarm, even though the freezer itself was operating correctly.
A start delay gives the logger time to adjust to the temperature of the environment before the readings begin.
A delayed start is usually a good idea when the whole logger is being placed inside the fridge, freezer, cool room or shipping container.
This includes situations where the logger has been stored at room temperature before use and is then placed directly into a cold environment.
Common examples include:
In these cases, a short delay can prevent the logger from recording its own cooling-down period as if it were a problem with the fridge, freezer or shipment.
You may not need a delayed start if the logger uses an external probe and the probe is already inside the monitored environment.
For example, some LogTag models have a probe that sits inside the fridge while the logger body remains outside. If the probe has not been removed from the fridge, it is already at the correct temperature. In that case, there is usually no need to wait for the probe to cool down.
The key question is this:
Is the part of the logger that measures temperature already at the temperature you want to monitor?
If the answer is yes, a delay may not be necessary.
If the answer is no, a delay is usually worth considering.
The right delay depends on the situation, but 5 to 10 minutes is often enough for many common fridge and freezer applications.
A small logger placed into a fridge may only need a short delay. A logger placed into a freezer may take a little longer to cool down. Packaging, airflow and where the logger is placed can also make a difference.
The aim is not to hide genuine temperature problems. The aim is simply to stop the logger from alarming because it was warm before it went into the monitored space.
A delayed start is useful, but it should not be used to cover up bad handling or poor temperature control.
If the fridge, freezer or shipment is genuinely too warm, the logger should record that. If stock has been left out of temperature control for too long before the logger is started, a delay will not solve that problem.
Delayed start is best used for one specific purpose: allowing the logger itself to reach the monitored temperature before logging begins.
Use a delayed start when the logger itself is going into the fridge, freezer or cold environment.
You may not need a delayed start when the logger has an external probe and the probe has stayed inside the monitored environment.
It is a small setting, but it can prevent a lot of confusion when reviewing results later.
Latency, when it comes to temperature logging, refers to the delay between a change in temperature and when that change is detected and recorded by the logger. This delay can be due to the sensor’s design, the materials it’s placed in, or the logging interval. While it might sound like a disadvantage, latency can actually serve a useful purpose in certain environments—particularly where short-term temperature spikes are common but not harmful.
For example, in a busy commercial fridge, the temperature may briefly rise every time the door is opened. A logger with high latency won’t immediately react to these short fluctuations, helping to avoid unnecessary alarms or false data indicating a problem when there isn’t one. In these cases, a slight delay in response acts like a filter, focusing attention on real issues—such as prolonged exposure to unsafe temperatures—while ignoring the everyday ups and downs that don’t affect product quality or safety.
Depending on the type of logger you have, connecting your logger to your PC means either:
First Generation LogTags use a separate Reader (sometimes called a dock) for configuration and for downloading recorded data.
The Second Generation loggers only require a USB port or cable. Apart from saving the cost of the Reader, this makes them much better suited for shipping, because the recipient doesn’t need a LogTag Reader to download a report about the shipment’s journey.
