This paper examines a battery backup circuit and Control Board designed by the author to eliminate hazardous conditions and inconveniences experienced whenever the local power grid fails. Fortunately, power outages in this country are usually cleared on the average within an hour to ninety minutes, although many can last for days.
Everyone who has a system with pumps relies on the grid to keep the pumps running. In certain cases, systems need to be shut down immediately upon loss of power, either to avoid damage to the system or for safety reasons. In the case of oil or gas fed furnaces, fuel is shut off when power fails. In the case of wood or coal burning furnaces there is a need to avoid any buildup of steam. In such cases the fire cannot usually be extinguished and re-ignited quickly upon return of power. A reliable battery backup system can help to avoid such situations and the inconveniences associated with power failures.
Hopefully, this paper offers readers, from the casual reader to the technically competent reader, an opportunity to learn enough to understand generally how a battery backup system works and specifically how a controller functions. The casual reader can get a grasp of the system by reading and understanding only sections 1 and 2, while a more detailed description follows in sections 3 and 4. The material presented in this paper concentrates mainly on the Control Board. Another paper will describe the interface connections, internal and external to the electrical enclosure.