Power requirements vary from application to application depending on the instruments in the system, datalogger scan rate, ambient temperature, and availability of a power source to recharge system batteries. Satellite transmitters, for example, have large power needs. Other stations might be expected to operate unattended with minimal recharge over long periods. These systems may require a rechargeable power supply with more capacity than those typically sold with our dataloggers (e.g., PS12LA, CR23X and CR5000 rechargeable battery bases).

Campbell Scientific offers the BP12 and BP24 battery packs for these systems, which have nominal ratings of 12 and 24 Ahrs, respectively. These batteries should be connected to a charging regulator, typically our CH12R, and a charging source, such as ac power or a solar panel. The charging source powers the datalogger system while float-charging the batteries. The batteries provide back-up power to the datalogger if the charging source is interrupted. The charging regulator also controls the current flowing to the battery and prevents the battery current from flowing to the charging source.

For information about analyzing your system's power requirements, see our Power Supply brochure or CSI Application Note 5-F.