Intermittent fault detection system

• US 5,017,910 A
• Filed: 08/24/1989
• Issued: 05/21/1991
• Est. Priority Date: 08/24/1989
• Status: Expired due to Term

• Current Assignee: Deere & Company
• Original Assignee: Deere & Company
• Inventors: Farber, Arnold S., Lang, Stephen P., Smart, David C.
• Primary Examiner(s): Orsino, Joseph A.
• Assistant Examiner(s): Hofsass, Jeffery A.
• Application Number:
  US07/397,820
• Time in Patent Office: 635 Days
• Field of Search: 340/635, 340/657, 340/647, 340/650, 340/651, 364/900, 324/539, 324/540, 324/542
• US Class Current: 340/635
• CPC Class Codes: G01R 31/2834 Automated test systems [ATE]; using microprocessors or computers G01R31/317 takes precedence; ATE for detection of defective computer hardware G06F11/2736

Abstract

A monitoring or control system includes a plurality of senders or sensors which are coupled to a central control unit by separate cables. The control unit includes a microprocessor which executes an intermittent fault detection algorithm while an operator manually flexes each cable in turn. When a cable with a fault is manipulated the algorithm responds by energizing a horn.

Claims

1. In a system having a plurality of devices, each device coupled to a central unit via a corresponding electrical cable, a method of detecting intermittent faults in the cables, the method comprising periodically performing the following steps while the cables are manually manipulated in sequence:

a. generating and storing a first set of status signal representing electrical parameters of the cables;

b. subsequently generating a second set of status signals representing electrical parameters of the cables;

c. comparing the second set to the first set and generating an audible alarm signal if the second set differs from the first set, and

d. replacing the first set with the second set.

2. A method for detecting intermittent faults in an electrical circuit having a plurality of devices, each connected to a central unit via a corresponding one of a plurality of conductors, the method comprising:

a. storing in a memory a first set of status signals representing electrical parameters associated with the plurality of devices and communicated to the central unit via the conductors;

b. storing a second set of status signals representing electrical parameters associated with the devices at a time subsequent to the storing of the first set of status signals;

c. comparing the second set of status signals to the first set and generating an audible alarm signal if the sets differ from each other;

d. redesignating the second set of status signals as the first set of status signals; and

e. periodically repeating steps a. through d.