REDUNDANT BUS FAULT DETECTION

• US 20140281752A1
• Filed: 03/15/2013
• Published: 09/18/2014
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Siemens Schweiz AG (Siemens AG)
• Original Assignee: Siemens AG
• Inventors: Schermann, Harald, Strelecki, Paul Richard, Baroncini, Vincent, Torres, Pablo, Keating, Michael J.
• Granted Patent: US 9,244,753 B2
• Time in Patent Office: Days
• US Class Current: 714/56
• CPC Class Codes: G06F 11/0745 in an input/output transactions management context input/output processing in general G06F13/00
• CPC Class Codes: G06F 11/0757 by exceeding a time limit, i.e. time-out, e.g. watchdogs
• CPC Class Codes: G06F 11/2007 using redundant communication media
• CPC Class Codes: G06F 11/3013 where the computing system is an embedded system, i.e. a combination of hardware and software dedicated to perform a certain function in mobile devices, printers, automotive or aircraft systems testing or monitoring of control systems or parts thereof G05B23/02
• CPC Class Codes: G06F 11/325 by lamps or LED's
• CPC Class Codes: G06F 11/326 for error or online/offline status
• CPC Class Codes: G06F 11/327 Alarm or error message display
• CPC Class Codes: G08B 29/123 of line circuits
• CPC Class Codes: G08B 29/16 Security signalling or alarm systems, e.g. redundant systems

Abstract

A system and method for an approach of detecting faults in a redundant bus system based upon four timers.

Claims

1. A building automation system, comprising:

a first communication bus having a first pathway with a first propagation delay;

a second communication bus having a second pathway with a second propagation delay, where the second pathway is redundant to the first pathway and the first propagation delay is different from the second propagation delay;

a bus controller coupled to at least one peripheral device by the first communication bus and the second communication bus and where a first timer is associated with a time period from power up until activity occurs on each of the first communication bus and the second communication bus; and

an at least one visual indicator that is associated with expiration of the first timer when activity is not detected and at least one of the first communication bus or second communication bus being deactivated in response to the expiration of the first timer.

2. The building automation system of claim 1, where the first communication bus and second communication bus are controller area networking (CAN) buses.

3. The building automation system of claim 1, where the at least one of the first communication bus or second communication bus being deactivated is making that at least one of the first communication bus or second communication bus a non-primary communication bus.

4. The building automation system of claim 1, where the first timer is set to a first predetermined value.

5. The building automation system of claim 3, where the first predetermined value of 20 seconds.

6. The building automation system of claim 1, were the at least one visual indicator is a light emitting diode.

7. A building automation system, comprising:

a first communication bus having a first pathway with a first propagation delay;

a second communication bus having a second pathway with a second propagation delay, where the second pathway is redundant to the first pathway and the first propagation delay is different from the second propagation delay;

a bus controller coupled to at least one peripheral device by the first communication bus and the second communication bus and where a first timer is associated with a periodic ping on each of the first communication bus and the second communication bus; and

an at least one visual indicator that is associated with expiration of the first timer when a response to the periodic ping is not detected and at least one of the first communication bus or second communication bus being deactivated in response to the expiration of the first timer.

8. The building automation system of claim 7, where the first communication bus and second communication bus are controller area networking (CAN) buses.

9. The building automation system of claim 7, where the at least one of the first communication bus or second communication bus being deactivated, is making at least one of the first communication bus or second communication bus a non-primary communication bus.

10. The building automation system of claim 7, where the first timer is set to a first predetermined value.

11. The building automation system of claim 10, where the first predetermined value of 110 milliseconds.

12. The building automation system of claim 7, were the at least one visual indicator is a light emitting diode.

13. A building automation system, comprising:

a first communication bus having a first pathway with a first propagation delay;

a second communication bus having a second pathway with a second propagation delay, where the second pathway is redundant to the first pathway and the first propagation delay is different from the second propagation delay;

a bus controller coupled to at least one peripheral device by the first communication bus and the second communication bus and where a first timer is associated with a bit time on each of the first communication bus and the second communication bus; and

an at least one visual indicator that is associated with the first timer when a bit is detected prior to expiration of the first timer and at least one of the first communication bus or second communication bus being deactivated in response to the bit being detected prior to expiration of the first timer.

14. The building automation system of claim 13, where the first communication bus and second communication bus are controller area networking (CAN) buses.

15. The building automation system of claim 13, where the at least one of the first communication bus or second communication bus being deactivated, is making at least one of the first communication bus or second communication bus a non-primary communication bus.

16. The building automation system of claim 13, where the first timer is set to a first predetermined value.

17. The building automation system of claim 16, where the first predetermined value of 110 milliseconds.

18. The building automation system of claim 13, were the at least one visual indicator is a light emitting diode.

19. A building automation system, comprising:

a first communication bus having a first pathway with a first propagation delay;

a second communication bus having a second pathway with a second propagation delay, where the second pathway is redundant to the first pathway and the first propagation delay is different from the second propagation delay;

a bus controller coupled to at least one peripheral device by the first communication bus and the second communication bus and where a first timer is associated with a periodic ping on each of the first communication bus and the second communication bus; and

an at least one visual indicator that is associated with expiration of the first timer when a response to the periodic ping is not detected and at least one of the first communication bus or second communication bus being deactivated in response to the expiration of the first timer.

20. The building automation system of claim 19, where the first communication bus and second communication bus are controller area networking (CAN) buses.

21. The building automation system of claim 19, where the at least one of the first communication bus or second communication bus being deactivated, is making at least one of the first communication bus or second communication bus a non-primary communication bus.

22. The building automation system of claim 19, where the first timer is set to a first predetermined value.

23. The building automation system of claim 22, where the first predetermined value of 15 microseconds.

24. The building automation system of claim 19, were the at least one visual indicator is a light emitting diode.

25. A building automation system, comprising:

a first communication bus having a first pathway with a first propagation delay;

a second communication bus having a second pathway with a second propagation delay, where the second pathway is redundant to the first pathway and the first propagation delay is different from the second propagation delay;

a bus controller coupled to at least one peripheral device by the first communication bus and the second communication bus and where a first timer is associated with a difference between the first propagation delay and the second propagation delay with the first timer being activated upon receipt of a first message on the first communication bus; and

an at least one visual indicator that is associated with expiration of the first timer prior to receipt of the first message on the second communication bus and the second communication bus being deactivated in response to the expiration of the first timer.

26. The building automation system of claim 25, where the first communication bus and second communication bus are controller area networking (CAN) buses.

27. The building automation system of claim 25, where the first timer is set to a first predetermined value.

28. The building automation system of claim 25, where the first predetermined value of 15 microseconds.

29. The building automation system of claim 25, were the at least one visual indicator is a light emitting diode.

30. A building automation system, comprising:

a first communication bus having a first pathway with a first propagation delay;

a second communication bus having a second pathway with a second propagation delay, where the second pathway is redundant to the first pathway and the first propagation delay is different from the second propagation delay;

a bus controller coupled to at least one peripheral device by the first communication bus and the second communication bus, and the bus controller includes;

a first timer is associated with a time period from power up until activity occurs on each of the first communication bus and the second communication bus where an at least one visual indicator which is activated with expiration of the first timer when activity is not detected and at least one of the first communication bus or second communication bus being deactivated in response to the expiration of the first timer;

a second timer associated with a periodic ping on each of the first communication bus and the second communication bus where the at least one visual indicator is activated with expiration of the second timer when a response to the periodic ping is not detected and where at least one of the first communication bus or second communication bus being deactivated in response to the expiration of the second timer;

a third timer is associated with a periodic ping on each of the first communication bus and the second communication bus and the at least one visual indicator is activated with expiration of the first timer when a response to the periodic ping is not detected and where at least one of the first communication bus or second communication bus being deactivated in response to the expiration of the third timer; and

a fourth timer is associated with a difference between the first propagation delay and the second propagation delay with the fourth timer being activated upon receipt of a first message on the first communication bus and where the at least one visual indicator is activated upon expiration of the fourth timer prior to receipt of the first message on the second communication bus and the second communication bus being deactivated in response to the expiration of the first timer.