Abstract: A portable measurement device and method for measuring a parameter value of a battery. The measurement device connects a large resistive load to a battery being tested. The load is connected to the battery through a first set of kelvin connected clamps and a switch. A microprocessor measures open and closed circuit voltages via a second set of kelvin connected jaws. The microprocessor determines voltage drop curve data based on the measure open and closed circuit voltages. The microprocessor compares the voltage drop curve data to voltage drop profile data for a particular parameter to determine the parameter value for the battery.

Abstract: The apparatus relates to a dual load tester that is hand held and highly portable. The dual load tester includes two resistive loads, and the two resistive loads may be used in series or one of the resistive loads may be used individually to test batteries, charging systems and starter motors of different voltage and current ratings. The operator of the device may, by closing the appropriate switch, first test a 12-volt battery and then test a 24-volt battery. In a similar manner, the tester may be used to test charging systems and starter motors of different voltage and current ratings. The testing functions of the dual load tester may be automated for testing various devices. The dual load tester includes a first resistive load and a second resistive load. The resistive loads may be used together or individually to test a battery, charging system, starter motor or other device.