Commonwealth Edison Company

Merlin E Burkum

Timothy M O'Regan

Charles M Gabriel

Chang E Kang

L Alan Lowry

An apparatus for measuring charge state of a battery having multiple cells includes a transmitter that is connected to the battery to apply a test signal across the battery. This test signal is preferably a continuous square wave signal having a frequency less than 3 Hz. The test signal alternates between a voltage adequate to charge the battery and a lower voltage, and the charging voltage is retained for a time sufficient to allow a polarization voltage to develop across individual cells. A receiver is connected to the cell to monitor the polarization voltage across a cell as it develops in response to the test signal. This polarization voltage can be monitored for example using a DC voltmeter, or by displaying the voltage versus time waveform. In either case an accurate indication of the state of the charge of the cell is provided.

Apparatus and method for utilizing polarization voltage to determine

A testing device measures the impedance of secondary cells that form a battery, such as a lead acid battery, while the battery is in a float charge condition and connected to an active electrical load. The impedance measurement is made at a frequency selected to be different from those frequencies otherwise present in the charger-load circuit. A first application of the testing device monitors the battery for a change in impedance that can signal a developing defect in one or more individual cells or intercell connections that can prevent the battery from delivering its stored energy to the load. In a second application, the testing device is used to compare the impedance of individual cells and electrical connections to locate faulty components.

Apparatus and method for measuring battery condition

An apparatus for locating ground faults on direct current control systems includes a low frequency current generator having a variable output, a Hall-effect current probe for detecting the low frequency current produced by the generator, a filter and amplifier connected to the output of the Hall-effect current probe for identifying and amplifying the low frequency signal and a read-out element connected to the output of the amplifier to indicate the relative magnitude of the low frequency signal. A method for locating ground faults on direct current control system while the system is energized is described.

Apparatus and method for locating ground faults

An apparatus for determining the operating condition of capacitors of the type used for power factor correction on electric distribution systems is assembled in two sections. A first power supply device supplies an alternating electric current to a de-energized capacitor without removing it from its installed position and a second power measurement device, utilizing either a split-core Hall-device or a special distributed winding, measures the magnitude of the electric current entering the capacitor being tested.

Apparatus for identifying defective electric power distribution

An apparatus for identifying defective substation capacitors includes a variable power supply section for supplying an alternating electric current to a de-energized substation capacitor bank without disconnecting the individually fused capacitor from the capacitor bus and a second power measurement section for measuring the magnitude of the electric current entering the capacitor being tested.

Apparatus for identifying defective substation capacitors

An apparatus for determining the operating condition of capacitors of the type used for power factor correction on electric distribution systems is assembled in two sections. A first power supply device supplies an alternating electric current to a de-energized capacitor without removing it from its installed position and a second power measurement device, utilizing a split-core Hall-device, measures the magnitude of the electric current entering the capacitor being tested.

Growing community of inventors

Elmhurst, IL, United States of America

Merlin E Burkum