The CH150 is a charging regulator for an external rechargeable 12 V VRLA (valve-regulated lead-acid) battery, such as the BP12 or BP24 offered by Campbell Scientific. Charging power for the CH150 is typically supplied by an unregulated solar panel, AC/AC transformer, or AC/DC converter. The CH150 provides charging with temperature compensation for optimal charging and battery life. A maximum power point tracking algorithm is incorporated for solar inputs to maximize available solar charging resources.