Patent ID: 8471531

Claim:
A method for controlling an uninterruptible power supply (UPS), comprising: setting by at least one processor a reserve level based on a user input; estimating by said at least one processor a level of power available in at least one battery, comprising: retrieving from memory a remaining life value for said at least one battery; determining whether said at least one battery is being used to power at least one load; measuring a temperature of at least said at least one battery; and using at least one algorithm, said remaining life value, said determination of whether said at least one battery is being used to power said at least one load, and said temperature to estimate said remaining life of said at least one battery; determining by said at least one processor whether the estimated level meets the set reserve level; determining by said at least one processor whether there is a power outage; and during the power outage, effecting by said at least one processor a shutdown of said UPS when the estimated level fails to meet the set reserve level, and utilizing the battery power after said shutdown and when a user demand for backup power is received.