Vehicle current drain tester with memory saver
First Claim
1. A vehicle nominal current drain tester for testing nominal current drawn by a vehicle'"'"'s electrical circuit from the vehicle battery when the ignition is off, the tester comprising:
- a measurement current loop comprising;
first and second tester terminals for connection in series with the electrical circuit;
first and second voltage source terminals coupled in series with the first and second tester terminals; and
a current sensor coupled in series with the first and second tester terminals and the first and second voltage source terminals, which generates a measurement signal representative of nominal current drawn by the electrical circuit through the measurement current loop;
a first offset circuit coupled to the current sensor which applies a first offset to the measurement signal and provides a fail output as a function of whether the measurement signal exceeds the first offset, wherein the first offset represents a first selected nominal drain current level drawn by the electrical circuit when the ignition is off; and
a fail indicator coupled to the first offset circuit and responsive to the fail output.
5 Assignments
0 Petitions
Accused Products
Abstract
A vehicle current drain tester tests nominal current drain through a vehicle electrical system while preserving on-board vehicle memory. The tester includes a measurement current loop, an offset circuit and a fail indicator. The current loop includes first and second tester terminals for connection to the electrical circuit, first and second voltage source terminals for connection to a voltage source and a current sensor. The current sensor generates a measurement signal in response to current flowing in the current loop. The offset circuit is coupled to the current sensor and applies an offset to the measurement signal which represents a selected drain current level in the vehicle. The offset circuit generates a fail output signal as a function of whether the measurement signal exceeds the offset. The fail indicator is coupled to the offset circuit and is responsive to the fail output signal.
-
Citations
20 Claims
-
1. A vehicle nominal current drain tester for testing nominal current drawn by a vehicle'"'"'s electrical circuit from the vehicle battery when the ignition is off, the tester comprising:
-
a measurement current loop comprising; first and second tester terminals for connection in series with the electrical circuit; first and second voltage source terminals coupled in series with the first and second tester terminals; and a current sensor coupled in series with the first and second tester terminals and the first and second voltage source terminals, which generates a measurement signal representative of nominal current drawn by the electrical circuit through the measurement current loop; a first offset circuit coupled to the current sensor which applies a first offset to the measurement signal and provides a fail output as a function of whether the measurement signal exceeds the first offset, wherein the first offset represents a first selected nominal drain current level drawn by the electrical circuit when the ignition is off; and a fail indicator coupled to the first offset circuit and responsive to the fail output. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
16. A vehicle current drain tester for testing current drain through an electrical circuit in a vehicle having an on-board memory, comprising:
-
means for providing power to the vehicle'"'"'s electrical circuit; means for sensing current flow in the electrical circuit and generating a measurement signal indicative of the current flow; first offset means for offsetting the measurement signal with a first offset representative of a predetermined maximum drain current; first indicating means for indicating whether the measurement signal exceeds the first offset; second offset means for offsetting the measurement signal with a second offset, which is less than the first offset; and second indicating means for indicating whether the measurement signal exceeds the second offset. - View Dependent Claims (17, 18)
-
-
19. A vehicle nominal current drain tester for testing nominal current drawn by a vehicle'"'"'s electrical circuit from the vehicle battery when the ignition is off, the tester comprising:
-
a measurement current loop comprising; first and second tester terminals for connection in series with the electrical circuit; first and second voltage source terminals coupled in series with the first and second tester terminals; and a current sensor coupled in series with the first and second tester terminals and the first and second voltage source terminals, which generates a measurement signal representative of nominal current drawn by the electrical circuit through the measurement current loop; a voltage offset generator providing an offset voltage which represents a selected nominal drain current level drawn by the electrical circuit when the ignition is off; a comparator having first and second inputs and a comparator output, wherein the first input is coupled to the current sensor, the second input is coupled to the voltage offset generator and the comparator output provides a fail output in response to a comparison of the measurement signal and the offset voltage; and a fail indicator coupled to the comparator output and responsive to the fail output. - View Dependent Claims (20)
-
Specification