THERMOSTAT RELAY CONTROL

• US 20070045432A1
• Filed: 08/30/2005
• Published: 03/01/2007
• Est. Priority Date: 08/30/2005
• Status: Active Grant

• Current Assignee: Ademco Inc. (Resideo Technologies, Inc.)
• Original Assignee: Honeywell International Inc.
• Inventors: Juntunen, Robert
• Granted Patent: US 7,673,809 B2
• Time in Patent Office: Days
• US Class Current: 236/46.R
• CPC Class Codes: F23N 2225/12 room temperature
• CPC Class Codes: F23N 2241/02 Space-heating
• CPC Class Codes: F23N 5/203 using electronic means
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/46 Improving electric energy efficiency or saving
• CPC Class Codes: F24F 11/88 Electrical aspects, e.g. circuits
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 2120/00 Control inputs relating to users or occupants
• CPC Class Codes: G05D 23/1919 characterised by the type of controller

Abstract

The present invention, in illustrative embodiments, includes methods and devices for reducing power consumption in a thermostat by adjusting pulse levels (duration and/or voltage) that are used to control an HVAC relay in light of variations of ambient conditions or other relay conditions. In some illustrative embodiments, an ambient condition is observed using existing thermostat features, such as, for example, a temperature sensor, and used to adjust pulse parameters.

Claims

1. A thermostat for managing one or more conditions in a controlled space, the thermostat comprising:

a temperature sensing element for sensing a sensed temperature;

a relay;

a controller coupled to the temperature sensing element and the relay, the controller applying an electrical pulse to the relay to selectively set or reset the relay, wherein at least one parameter of the electrical pulse is set in response to the sensed temperature.

2. The thermostat of claim 1 wherein the relay is a latching relay.

3. The thermostat of claim 1 wherein the electrical pulse has a duration, and the controller is adapted to set at least one of the duration of the electrical pulse and an amplitude of the electrical pulse in response to the sensed temperature.

4. The thermostat of claim 1 wherein the electrical pulse has a duration and an amplitude, and the controller is adapted to set both the duration and the amplitude of the electrical pulse in response to the sensed temperature.

5. The thermostat of claim 1 wherein the electrical pulse has an amplitude and a duration, and the controller is adapted such that, at a first temperature the electrical pulse has a first duration and a first amplitude, and at a second temperature higher than the first temperature, the electrical pulse has a second duration and a second amplitude, wherein at least one of the following conditions is true:

the second duration is longer than the first duration;

the second amplitude is greater than the first amplitude.

6. The thermostat of claim 1 wherein the thermostat is adapted for use in an HVAC system, and wherein the relay is configured for relaying power for at least one of a ventilation system, a heating system, or an air conditioning system.

7. The thermostat of claim 1 wherein the controller has access to a lookup table for determining parameters for the electrical pulse using the temperature.

8. The thermostat of claim 1 wherein the controller uses a formula to determine parameters for the electrical pulse using the temperature.

9. A method of operating a thermostat, the thermostat including an ambient condition sensing element and a relay, the thermostat being coupled to at least one HVAC device having on and off states such that setting or resetting the relay changes the state of the coupled HVAC device, the method comprising:

determining whether the state of the coupled HVAC device is to be changed and, if so;

observing the ambient condition;

selecting one or more parameters for an electrical pulse by reference to the ambient condition; and

delivering the electrical pulse to the relay to set or reset the relay.

10. The method of claim 9 wherein the relay is a latching relay.

11. The method of claim 9 wherein the step of selecting one or more parameters for an electrical pulse includes selecting at least one of a duration for the pulse and an amplitude for the pulse.

12. The method of claim 9 wherein the step of selecting one or more parameters for an electrical pulse includes selecting a duration and an amplitude for the pulse.

13. The method of claim 9 wherein the ambient condition is temperature.

14. The method of claim 13 wherein the electrical pulse has an amplitude and a duration, and the step of selecting one or more parameters for an electrical pulse is performed such that:

at a first temperature the electrical pulse has a first duration and a first amplitude; and

at a second temperature higher than the first temperature, the electrical pulse has a second duration and a second amplitude;

wherein at least one of the following conditions is true;

the second duration is longer than the first duration;

the second amplitude is greater than the first amplitude.

15. The method of claim 13 wherein the step of selecting parameters for an electrical pulse is performed by reference to a lookup table reliant on the temperature.

16. The method of claim 14 wherein the step of selecting parameters for an electrical pulse is performed by the use of a formula reliant on the temperature.

17. A thermostat for managing one or more conditions in a controlled space, the thermostat comprising:

a sensing component adapted for sensing an ambient condition;

a relay; and

a controller coupled to the sensing component and the relay, wherein the controller reads a value from the sensing component that is related to the sensed ambient condition;

the controller further providing an electrical pulse to the relay to selectively set or reset the relay, wherein at least one parameter of the electrical pulse is determined in response to an operating condition of the thermostat and, as operating conditions of the thermostat change, the at least one parameter is adjusted.

18. The thermostat of claim 17 wherein the ambient condition is temperature, and the operating condition includes the sensed temperature.

19. The thermostat of claim 17 wherein the operating condition includes a factor related to the age of the relay.

20. The thermostat of claim 17 wherein the operating condition includes both a factor related to the age of the relay and the sensed ambient condition.