Confirm that the battery voltage is above the threshold value stated in the technical specifications for you instrument. The instrument won't measure if the voltage supply is too small. This includes measurements of the other sensors as well. Insufficient power supply will therefore be easily detectable in the rest of the data.
If somehow the power alternates between on/off or above/below the threshold, the data will contain gaps where no measurements have been made. This can be due to a multitude of reasons, on which the instruments error code might be able to provide further detail. When batteries are depleted, the voltage will drop below the threshold. The consequence is not gaps in the data set, but the measurements will stop entirely. When external power is supplied through long cables, be sure to consider the voltage drop due to resistance in the cable.
Before deployment check the date stamp on your batteries and be aware that batteries discharge over time. Make sure to store your batteries in the right temperature and humidity. Read more about the storage of batteries here. We always recommend to work with fresh batteries. If you unsure of the remaining capacity on a used battery, we recommend carrying out a short test deployment and compare the loaded voltage to the expected range for the used battery type. Carrying out this test prior to a deployment, can prevent the possible loss of data.
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