Abstract: An apparatus and method for controllably charging and discharging individual battery cells or groups of battery cells in a string of batteries employed as a back-up power supply is provided. The apparatus includes battery supply modules for at least partially isolating battery strings from the load bus and primary power supply. The partial isolation is effected by a switching network including two controlled switches arranged in parallel to selectively isolate the string of batteries. In certain disclosed embodiments, one of the controlled switches is turned on to connect the string of batteries to the load bus until the other controlled switch closes. The system includes a main power supply that supplies a power bus to a regulator in each battery supply module, which is used for charging the battery string, and a discharge bus to each battery supply module for discharging the batteries.

Abstract: Instantaneous current and voltage values are digitized at each of a plurality of electrical utility customer sites and integrated by a processor to calculate electrical power consumed at each customer site. A communication interface couples the processor at each customer site to a central processor in a central utility site to communicate the power consumed values of each customer site to the central utility site. In a preferred embodiment, the automatic meter reader apparatus is mounted in an electrical watthour meter socket adapter which plugs into a watthour meter socket at each customer site. Telephone modem circuitry mounted in the socket adapter connects to telephone lines to communicate calculated power values from each customer site to the central utility site.