At what voltage should batteries be replaced?

Depending on the total power demand of an X2-SDL system, the minimum acceptable operation voltage can vary. Factors such as the number and types of connected sensors, logging interval, transmission interval etc. influence the required power supply.

A general rule of thumb is to consider replacing the X2-SDL’s (16) D-Cell batteries when the voltage falls below 9.0V. At a minimum, however, replace X2-SDL batteries when the reported system voltage falls to 8V (1V per cell). Information on battery replacement is available here.

NOTE: Below 7.2V, there is the potential that the logger may continuously reset and damage the data logger storage SD card in the process.


Figure 1: When the Secondary Power diagnostic reported to WQData LIVE by the X2-SDL drops to 9.0V, replace batteries soon.