BUILDING MANAGEMENT SYSTEM WITH DYNAMIC MASTER CONTROLLER SELECTION

• US 20180225244A1
• Filed: 06/05/2017
• Published: 08/09/2018
• Est. Priority Date: 02/07/2017
• Status: Active Grant

• Current Assignee: Johnson Controls Technology Company (Johnson Controls International plc)
• Original Assignee: Johnson Controls Technology Company (Johnson Controls International plc)
• Inventors: Dorneanu, Radu M., Noboa, Homero L., Weller, Kim K.
• Granted Patent: US 10,642,770 B2
• Time in Patent Office: Days
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G05B 19/0428 Safety, monitoring G05B19/0423 takes precedence
• CPC Class Codes: G05B 2219/2231 Master slave
• CPC Class Codes: G05B 2219/2237 Selection of master or slave
• CPC Class Codes: G05B 2219/2642 Domotique, domestic, home control, automation, smart house
• CPC Class Codes: G06F 11/073 in a memory management context, e.g. virtual memory or cache management memory management G06F12/00; testing of static memory units G11C29/00
• CPC Class Codes: G06F 11/0766 Error or fault reporting or storing
• CPC Class Codes: G06F 11/3006 where the computing system is distributed, e.g. networked systems, clusters, multiprocessor systems multiprogramming arrangements G06F9/46; allocation of resources G06F9/50
• 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 11/3058 Monitoring arrangements for monitoring environmental properties or parameters of the computing system or of the computing system component, e.g. monitoring of power, currents, temperature, humidity, position, vibrations thermal management in cooling arrangements of a computing system G06F1/206
• CPC Class Codes: G06F 13/374 using a self-select method with individual priority code comparator
• CPC Class Codes: G06F 16/00 Information retrieval; Database structures therefor; File system structures therefor

Abstract

A building management system includes a communications bus, an old master controller device; and slave devices. The slave devices are configured to detect that the old master controller device has stopped communicating over the communications bus and to perform an algorithm to determine a new master controller device from the slave devices. The algorithm is based on a device identifier associated with each of the slave devices. The new master controller device is further configured to assume the functions of the master controller device. The functions of the master controller device include transmitting control signals to the slave devices.

Claims

1. A building management system comprising:

a communications bus;

an old master controller device connected to the communications bus; and

a plurality of slave devices connected to the communications bus;

wherein the plurality of slave devices is configured to;

detect that the old master controller device has stopped communicating over the communications bus; and

perform an algorithm to determine a new master controller device from the plurality of slave devices, wherein the algorithm is based at least in part on a device identifier associated with each of the plurality of slave devices; and

wherein the new master controller device is configured to assume the functions of the master controller device, the functions of the master controller device comprising transmitting control signals to the plurality of slave devices.

2. The building management system of claim 1, wherein the new master controller device is further configured to detect that the old master controller device has resumed communicating over the communications bus.

3. The building management system of claim 2, wherein the new master controller device is further configured to relinquish the functions of the master controller device back to the old master controller device.

4. The building management system of claim 2, wherein the old master controller is further configured to operate as a slave device, wherein operating as a slave device comprises receiving control signals from the new master controller device.

5. The building management system of claim 1, wherein the device identifier associated with each of the plurality of slave devices is at least one of a serial number, a MAC address, and an IP address.

6. The building management system of claim 5, wherein the algorithm determines the new master controller device from the highest numbered device identifier associated with each of the plurality of slave devices.

7. The building management system of claim 5, wherein the algorithm determines the new master controller device from the lowest numbered device identifier associated with each of the plurality of slave devices.

8. The building management system of claim 1, wherein the device identifier associated with each of the plurality of slave devices is a text string.

9. The building management system of claim 8, wherein the algorithm determines the new master controller device from the alphabetically first device identifier associated with each of the plurality of slave devices.

10. A method for dynamically transferring control between multiple master controllers in a building management system, the method comprising:

detecting that an old master controller device has stopped communicating over a communications bus of the building management system;

performing an algorithm to determine a new master controller device from a plurality of slave devices connected to the communications bus, wherein the algorithm is based at least in part on a device identifier associated with each of the plurality of slave devices; and

assuming the functions of the master controller device, the functions of the master controller device comprising transmitting control signals to the plurality of slave devices.

11. The method of claim 10, the method further comprising detecting that the old master controller device has resumed communicating over the communications bus.

12. The method of claim 11, the method further comprising relinquishing the functions of the master controller device back to the old master controller device.

13. The method of claim 10, wherein the device identifier associated with each of the plurality of slave devices is at least one of a serial number, a MAC address, and an IP address.

14. The method of claim 13, wherein the algorithm determines the new master controller device from the highest numbered device identifier associated with each of the plurality of slave devices.

15. The method of claim 13, wherein the algorithm determines the new master controller device from the lowest numbered device identifier associated with each of the plurality of slave devices.

16. The method of claim 10, wherein the device identifier associated with each of the plurality of slave devices is a text string.

17. The method of claim 16, wherein the algorithm determines the new master controller device from the alphabetically first device identifier associated with each of the plurality of slave devices.

18. A building management system comprising:

a communications bus;

a plurality of slave devices connected to the communications bus; and

an old master controller device, wherein the old master controller device is configured to;

connect to the communications bus;

perform an algorithm to determine the new master controller device currently transmitting control signals to the plurality of slave devices, wherein the algorithm is based at least in part on a device identifier associated with each of the plurality of slave devices; and

assume the functions of the master controller device, the functions of the master controller device comprising transmitting control signals to the plurality of slave devices.

19. The building management system of claim 18, wherein the communications bus is a wireless network, and wherein the old master controller device is configured to connect to the wireless network following a period of wireless service interruption.

20. The building management system of claim 18, wherein the device identifier is at least one of a serial number, a MAC address, an IP address, and a text string.