SHORE POWER CORD GROUND WIRE CURRENT DETECTOR

• US 20090160427A1
• Filed: 12/19/2008
• Published: 06/25/2009
• Est. Priority Date: 12/21/2007
• Status: Active Grant

• Current Assignee: Power Products, LLC (Brunswick Corporation)
• Original Assignee: Actuant Corporation
• Inventors: Drake, William R., Kujawa, John A.
• Granted Patent: US 7,994,795 B2
• Time in Patent Office: Days
• US Class Current: 324/72
• CPC Class Codes: G01R 1/04 Housings; Supporting members; Arrangements of terminals
• CPC Class Codes: G01R 15/207 Constructional details independent of the type of device used
• CPC Class Codes: G01R 19/16566 Circuits and arrangements for comparing voltage or current with one or several thresholds and for indicating the result not covered by subgroups G01R19/16504, G01R19/16528, G01R19/16533

Abstract

A current detector and indicator unit are coupled to a shore power cord for monitoring for corrosion-causing galvanic current on the ground wire of the power cord. A current transducer coupled to the ground wire senses current and provides a signal corresponding to the magnitude of the sensed current to a microcontroller. The microcontroller compares the magnitude of the current signal to one or more predetermined thresholds and outputs signals to an indicator unit to display the level of galvanic activity accordingly.

Claims

1. A current sensing and notification device comprising:

means for detecting current in a ground wire of a shore power cord;

means for comparing current detected in the ground wire to a predetermined reference magnitude; and

means for indicating when the current detected in the ground wire is above the reference magnitude.

2. The device of claim 1, wherein the detecting means is a Hall effect based transducer, the comparing means include a microcontroller, and the indicating means includes at least one visual indicator.

3. The device of claim 2, wherein the visual indicator includes a first LED configured to be illuminated when a hot wire of the shore power cord is energized, and a second LED configured to be illuminated when the current detected in the ground wire is above the predetermined reference magnitude.

4. A shore power cord ground wire current detector comprising,

a current sensor coupled to a ground wire of a shore power cord operable to produce a signal representative of a sensed current;

a controller operable to receive and compare the current signal to a first reference magnitude; and

an indicator operable to provide a visual notification when the current signal is above the first reference magnitude.

5. The detector of claim 4, wherein the indicator is at least partially illuminated when the current signal produced by the sensor exceeds the first reference magnitude threshold.

6. The detector of claim 5, wherein the indicator includes a plurality of LEDs.

7. The detector of claim 6, wherein the controller is a microcontroller further operable to compare the current signal to a second reference magnitude.

8. The detector of claim 7, wherein the indicator comprises a first LED and a second LED;

wherein the first LED is illuminated when the current signal is above the first reference magnitude and the second LED is illuminated when the current signal is above the second reference magnitude.

9. The detector of claim 4, wherein the current sensor is a Hall effect-based current transducer.

10. The combination of a shore power cord and a current detector coupled thereto, the combination comprising:

a male plug configured to be electrically connected to a shore-based power supply;

a female connector configured to be received by a marine vessel electrical inlet;

a plurality of conductors disposed within a sheath extending between the plug and the connector, the plurality of conductors including at least one each of a hot, neutral, and ground conductor;

wherein the hot and neutral conductors are operable to provide electrical power from the AC power source to the marine vessel;

a current sensor coupled to the ground conductor operable to for detecting current in the ground conductor;

an indicator unit configured to provide an indication of current in the ground conductor; and

a microcontroller operable to receive and compare a signal from the current sensor to a predetermined reference magnitude.

11. The combination of claim 10, wherein the indicator unit includes a plurality of LEDs, wherein a first LED is illuminated if the current detected in the ground wire is above a first predetermined threshold and a second LED is illuminated if the current detected in the ground wire is above a second predetermined threshold.

12. The combination of claim 10, wherein the current sensor, indicator unit and microcontroller are disposed in the cord between the plug and the connector.

13. The combination of claim 10, wherein the current sensor, indicator unit and microcontroller are provided in a housing having a male plug and a female connector, and wherein one of the plug and connector are connected to the cord.