Abstract: There is disclosed an instrument for the continuous monitoring of emergency stand-by batteries during operation of the batteries. The invention monitors the emergency batteries during all discharge operations and records the usage and conditions of the batteries as well as alerts the operators when the discharge voltage of the batteries falls below the minimum required for the particular application. The instrument includes voltage, current and temperature sensors which generate signals that are applied through gain amplifiers to an analog to digital converter and then to a central processing unit. The central processing unit receives a reference voltage and has an independent emergency power supply. The central processing unit outputs signals to a liquid crystal display as well as to a printer and receives commands from a key pad. The central processor unit is supplied with a software operating program which is recorded on a ROM and has system RAM for non-volatile storage and a clock.

Abstract: An electric resistor coolant device is provided which comprises a lined tank for inclusion of water or other coolant containing a water inlet and outlet in which is submerged one or more electric resistor coils. The electric resistor coils are utilized in the load testing of certain electric power supply sources. Heat generated in the resistors by the electrical charge is carried away by the water contained in the tank, thereby increasing the capacity of the coils to carry electric current.

Abstract: A high speed, high impedance explosive circuit interrupter is disclosed which attenuates the magnitude and duration of fault currents accompanying circuit faults in electrical circuits protected by conventional circuit isolation apparatus. By so doing, the disclosed elements improve the operating speed and effectiveness of the breaking system and the protection of fault sensitive equipment.