Abstract: Energy utilized or consumed at a given location or facility causes pulses to be generated as a function of the instant rate of energy use, and such pulses are counted during succeeding discrete time intervals. The succeeding interval summation count values are recorded in digital form at respective discrete locations in a memory, particularly on an ultraviolet (UV) light-erasable PROM (EPROM) contained in a removable cartridge having a UV substantially opaque case. The interval summation count values are summed to provide a grand total energy or power utilization or consumption figure which is fed into and stored at a discrete location in the EPROM memory at the end of the recording period.

Abstract: Apparatus for detecting ferromagnetic material such as is present in an explosive cartridge being loaded into a borehole, e.g., according to the method described in U.S. Pat. No. 3,986,430, which includes an inductance coil connected in series with a resistor, separately rectifies and amplifies the AC voltages across the coil and resistor and connects them in series opposition. The value of the balancing resistance is adjusted so that the two rectified voltages are equal and opposite when no ferromagnetic material is present. When the unbalance voltage exceeds a threshold value, a signalling device is actuated.

Abstract: Energy utilized or consumed at a given location or facility causes pulses to be generated as a function of the instant rate of energy use, and such pulses are counted at succeeding discrete time intervals. The succeeding interval summation count values are recorded in digital form at respective discrete locations on an ultraviolet UV light-erasable PROM (EPROM) contained in a removable cartridge having a UV substantially opaque case. The interval summation count values are summed to provide a grand total energy or power utilization or consumption figure which is fed into and stored at a discrete location in the EPROM memory at the end of the recording period.