A two level, constant voltage float charge rectifier and battery surveillance apparatus is taught, having full-time battery and circuit operation surveillance. An electrical load and a battery are connected to the apparatus, in parallel, whereby the apparatus generally provides DC power directly to the load and maintains the battery on constant voltage float charge. In the event of an AC outage, the load is maintained from the battery. The apparatus automatically initiates a battery re-charging and equalization program if an AC outage is longer than a predetermined period, or in the event of deep discharge of the battery, or after a predetermined period of time (usually 30 days) since the last re-charging and equalization program. Constant surveillance includes an indication of the operation of the apparatus, including indication of low battery voltage, indication of a general failure alarm such as by failure of major components of the apparatus, and an indication at all times as to whether the apparatus is operating on a constant voltage float charge program or a battery re-charging and equalization program at a voltage level higher than the float charge level.
展开▼
