Circuit monitoring device

• US 20040051643A1
• Filed: 06/03/2003
• Published: 03/18/2004
• Est. Priority Date: 12/04/2000
• Status: Active Grant

• Current Assignee: Circuit Ventures LLC (Bradley David Liddle), Bullmore Technologies LLC (General Patent Corporation)
• Original Assignee: Eric Bullmore
• Inventors: Bullmore, Eric
• Granted Patent: US 7,256,683 B2
• Time in Patent Office: Days
• US Class Current: 340/635
• CPC Class Codes: G08B 13/22 Electrical actuation
• CPC Class Codes: G08B 17/10 Actuation by presence of smoke or gases , e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means
• CPC Class Codes: G08B 21/18 Status alarms G08B21/02 takes precedence
• CPC Class Codes: G08B 23/00 Alarms responsive to unspecified undesired or abnormal conditions
• CPC Class Codes: G08B 25/018 Sensor coding by detecting magnitude of an electrical parameter, e.g. resistance
• CPC Class Codes: G08B 25/14 Central alarm receiver or annunciator arrangements
• CPC Class Codes: G08B 29/22 Provisions facilitating manual calibration, e.g. input or output provisions for testing; Holding of intermittent values to permit measurement

Abstract

The circuit monitoring device is disclosed. The device is for monitoring circuit resistance. At configurable thresholds digital flags are triggered, the device can be used as a Security/Building management system. The device uses open technology is fully scaleable and allows programmable logic controllers to be used as security management systems. Using a soft logic option a PC could take the place of the PLC.

Claims

1. A method of monitoring the status of a measurable parameter of an electrical circuit, including the steps of:

measuring the magnitude of said parameter and generating an analog signal representative of said magnitude;

passing said analog signal to an analog to digital converter;

generating by the analog to digital converter a count value representative of said magnitude;

comparing said count value with a threshold value and assigning from the comparison a status signal, said status signal having two possible values which thereby indicates whether the count value is greater than or less than said threshold value;

transmitting said status signal via a communications network to a is display; and

displaying on the display an indication of the value of the status signal.

2. A method as defined in claim 1 wherein the threshold value is adjustable by a user.

3. A method as defined in claim 2 wherein the threshold value is adjustable by means of configuration software.

4. A method as defined in any one of claims 1 to 3 wherein said comparison is made with a plurality of threshold values and a status signal is assigned in respect of each of said threshold values, each of said status signals are transmitted via a communications network to a display;

and an indication of the value of each of the status signals is displayed on the display.

5. A method as defined in claim 4 wherein said plurality of status signals indicate respectively the following:

short circuit,

alarm 2,

normal,

alarm 1,

open circuit.

6. A method as defined in any one of the preceding claims, wherein said transmission of the status signal includes a wireless communication step.

7. A method as defined in claim 6 wherein the wireless communication employs the DeviceNet open network standard.

8. Apparatus for monitoring the status of a measurable parameter of an electrical circuit, the apparatus comprising:

measurement means for measuring the magnitude of said parameter and generating an analog signal representative of said magnitude;

analog to digital conversion means for generating from said analog signal a count value representative of said magnitude;

comparison means for comparing said count value with a threshold value and generating from the comparison a status signal, said status signal having two possible values which thereby indicates whether the count value is greater than or less than said threshold value;

transmission means for transmitting said status signal via a communications network to a display; and

display means for displaying an indication of said assigned status.

9. Apparatus as defined in claim 8 wherein the circuit is an electrical circuit containing at least one switchable element, the circuit including a first resistive component in series with the switchable element and second resistive component in parallel with the switchable element such that the status of the switchable element is reflected in the circuit resistance, and wherein the measurable parameter is the circuit resistance.

10. Apparatus as defined In claim 8 or 9 wherein the threshold value is adjustable by a user.

11. Apparatus as defined in claim 10 wherein the threshold value is adjustable by means of configuration software.

12. Apparatus as defined in claim 10 or 11 wherein the threshold value is held in non-volatile memory within the apparatus.

13. Apparatus as defined in any one of claims 8 to 12 wherein the comparison means includes a plurality of threshold values for assigning a corresponding plurality of status signals.

14. Apparatus as defined in claim 13 wherein said plurality of status signals indicate respectively the following:

short circuit,

alarm 2,

normal,

alarm 1,

open circuit.

15. Apparatus as defined in any one of claims 8 to 14 wherein said transmission means includes a wireless communication stage.

16. Apparatus as defined in claim 15 wherein the transmission means employs the DeviceNet open network standard.

17. A security management or building management system including apparatus as defined in any one of claims 8 to 16.

18. A fire system including apparatus as defined in any one of claims 8 to 16.

19. A building security management system comprising:

an electrical circuit containing a switchable element, the circuit including a first resistive component in series with the switchable element and a second resistive component in parallel with the switchable element such that the status of the switchable element is reflected in the electrical resistance of the circuit;

measurement means for measuring said resistance of the circuit and generating an analog signal representative of said resistance;

comparison means for comparing said count value with a threshold value and generating from the comparison a status signal, said status signal having two possible values which thereby indicates whether the count value is greater than or less than said threshold value;

transmission means for transmitting said status signal via a communications network to a display; and

display means for displaying an indication of said assigned status and thus of said switchable element.

20. A security management system as defined in claim 19 wherein the threshold value is adjustable by a user.

21. A security management system as defined in claim 20 wherein the threshold value is adjustable by means of configuration software.

22. A security management system as defined in claim 20 or claim 21 wherein the threshold value is held in non-volatile memory within the comparison means.

23. A security management system as defined In any one of claims 19 to 22 wherein the comparison means includes a plurality of threshold values for assigning a corresponding plurality of status signals.

24. A security management system as defined in claim 23 wherein said plurality of status signals indicate respectively the following:

short circuit,

alarm 2,

normal,

alarm 1,

open circuit.

25. A security management system as defined in any one of claims 19 to 24, wherein said transmission means includes a wireless communication stage.

26. A security management system as defined in claim 25 wherein said transmission means employs the DeviceNet open network standard.

27. A fire alarm system including a security management system as defined in any one of claims 19 to 26.