Why does the logger warm up when charging?
The logger contains a nickel-metal hydride battery pack for better performance and duration. This type of battery normally heats up during charging.
Tip
The devices generate heat while charging, especially toward the end of the charging cycle. This temperature increase itself is one of the parameters used by the device to detect that it is fully charged.
Optimal charging temperature is (from 15° - 25°C / 59°- 77°F) in ventilated rooms.
Ambient temperatures above 30°C / 86°F, will have a negative effect on charging.
Maximum charging temperature is 40°C / 104°F. If the device temperature exceeds this limit, the charging process will automatically interrupt until the device cools down again.
Minimum charging temperature is 0°C / 32°F. If the device temperature exceeds this limit, the charging process will automatically interrupt until the device warms up again.
We recommend placing loggers in an upright position when charging. If the loggers are leaning to the side and/or against each other, their temperature might increase. If the devices are leaning to the side or against each other, or the ambient temperature is too high, they may heat up, preventing the battery from fully charging.
The device should not be placed in a shipment directly after disconnecting from a charger. As the temperature sensor on the device is inside the USB connector cable, the device should be allowed at least 30 minutes to recover after charging for the temperature measurements to be accurate.