National Electric Code (NEC): The national Fire Protection Association standard NFPA 70 for electric wiring and apparatus.
National Fire Protection Association (NFPA): A non-profit organization for the development of fire and safety standards.
Reserve Capacity (RC): A standard rating for lead acid batteries, established by BCI (Battery Council International). The Reserve Capacity is the time in minutes that a given battery can be discharged at a constant rate of 25 amperes, at a temperature of 80 degrees Fahrenheit before the battery terminal voltage falls to 1.75 volts per cell (10.5 volts for a 12 volt system, 21 volts for a 24 volt system). Batteries are generally specified in terms of CCA and Reserve Capacity.
Transformer, Potential (PT): An instrument transformer used to supply voltage to protective relays or metering.
Uninterruptible Power Supply (UPS): A power supply which provides a source of electric power when the normal source is interrupted, without any voltage or frequency disturbance.