Single-use loggers are typically used when the logger will be sent to a 3rd party and you will not be returned (the price of the single-use is less than that of a multi-use logger). However if you are planning on internal temperature logging and the logger will remain within your company, a multi-use logger will be more cost effective in the long run.

Contactless loggers means that you do not need to manipulate the logger in order to extract the data. RAO (Radio Always On) means it is constantly looking for a device to pair and you do not need to press the “on” function, therefore it is very helpful to minimize the spread of germs and specifically designed with COVID-19 in mind.

An external sensor should be used:

• When the best response time is required. An external sensor will respond to changes in its environment slightly quicker than an internal sensor.
• When the temperature of the environment may not be within the operating temperature limits of the logger.
• When the logger cannot be placed within the cargo to be monitored and the temperature within the cargo is what is to be monitored. An external temperature sensor occupies far less space than a logger will.
• When the environment to be monitored is in a non-transparent and/or soundproof area and it is required to continuously view the status of the logger, like if the logger is in alarm mode. A logger does not need to be located in the same area as the external temperature sensor.

A logger, or external sensor, best functions when placed in a location where abnormal air currents and environmental changes are not an issue. For example, if you want to monitor the temperature of a room, it is advisable not to place the logger too close to the door. Otherwise, every time the door is opened the logger and/or external sensor will be subjected to the temperature of the neighboring room, even though the average temperature of the room being monitored may not actually significantly change. A real time monitoring system might be a viable alternative if you want to constantly stream data back to a designated location.