The drawings illustrate the best mode presently contemplated of carrying out the invention. In the drawings:
The interconnected hazardous condition detection system 10 utilizes a standard three-wire interconnect 18. The three-wire interconnect 18 provides main AC power from a source 20 to each of the various detectors 12, 14 and 16. The AC power from the source 20 is provided to each of the detectors by a power supply line (hot) 22 and a neutral line 24. As illustrated, each of the detectors is coupled to both the power supply line 22 and the neutral line 24. The three-wire interconnect system 10 further includes an interconnect line 26 that allows each of the detectors to communicate an interconnect signal between the various detectors.
As described previously with reference to the Schmurr '204 patent, it is important that the protocol of the interconnected hazardous condition detection system 10 allows for the interconnection of the various different types of detectors shown in
In the embodiment of the invention illustrated in
When the interconnect signal from the carbon monoxide detector 12 is present along the interconnect line 26, the smoke detector 14 and the combo detector 16 receive the interconnect signal, decode the signal and respond by generating an audible alarm that has the temporal pattern required for the detection of carbon monoxide.
Likewise, if the smoke detector 14 detects the presence of smoke in a concentration above an alarm threshold, the smoke detector 14 enunciates a local, audible alarm and generates an interconnect signal along the interconnect line 26.
Upon receiving the interconnect signal from the smoke detector 14, both the carbon monoxide detector 12 and the combo detector 16 recognize the representation of the detected smoke condition and generate the correct audible temporal pattern. The combo detector 16 can detect the presence of either smoke or carbon monoxide and generates the different interconnect signals depending upon the type of hazardous condition detected. Based upon the representation of the interconnect signal on the interconnect line 26, the carbon monoxide detector 12 and smoke detector 14 generate the correct temporal pattern for the type of hazardous condition detected and represented by the interconnect signal present on the interconnect line 26.
Although the interconnect signal present on the interconnect line 26 is taught as being a digital signal in the preferred embodiment of the invention, it should be understood that the interconnect signal can take various different forms depending upon the specific configuration of the various detectors 12, 14 and 16. However, in systems that use interconnect signals other than digital, the interconnect signal must still have a different value or pattern depending upon whether the interconnect signal represents a first sensed condition, such as the presence of carbon monoxide, or a second sensed condition, such as the presence of smoke. The at least two different interconnect signals represent the two different types of sensed conditions and are required to ensure that the interconnected detectors generate the correct temporal pattern based upon the detected hazardous condition.
As illustrated in
Although the auxiliary devices 46 are shown connected to the normally open output wire 42 and are activated upon movement of the movable contact 44, it should be understood that the auxiliary devices 46 could be connected to the normally closed output wire 38 and thus be de-activated when the movable contact 44 moves into contact with the normally open output wire 42. In such a configuration, the auxiliary devices 46 would remain active until the movable contact 44 is moved to the second position.
Referring now to
In the embodiment of the invention illustrated in
The interconnect interface 54 interprets the interconnect signal received at the input 56 and provides a signal to the control unit 48 on one of the two control lines 58, 60. For example, if the interconnect interface 54 detects the first sensed condition, the interconnect interface provides a high signal along control line 58 which is received by the control unit 48. Alternatively, if the detector interconnect interface 54 determines that the interconnect signal is indicating the detection of the second sensed condition, the interconnect interface 54 provides a high signal to the control unit 48 along the second control line 60. In this manner, the control unit 48 can determine whether the interconnect signal includes an indication of the first sensed condition or the second sensed condition. Although the preferred embodiment of the invention shows the control unit 48 separate from the interconnect interface 54, it should be understood that the interconnect interface 54 could be incorporated into the control unit 48 while operating within the scope of the present invention.
The multi-function line-powered relay module 28 of the present invention further includes a selection input 62 that is directly coupled to the control unit 48. The selection input 62 receives a selection signal from the selection wire 64 coupled to the selection input. In the embodiment of the invention illustrated in
When the selection wire 64 is connected to the power supply line 22, the control unit 48 receives an AC voltage at its selection input 62. When the selection wire 64 is connected to the neutral line 24, the control unit 48 receives a low, neutral voltage signal at the selection input 62. When the selection wire 64 is left unconnected, the control unit receives a floating voltage, which is interpreted by the control unit as being neither the zero voltage ground level nor the power input voltage level. In this manner, the selection line 64 can provide a selection signal to the control unit 48 having one of three states.
Although the line-powered relay module 28 shown in the Figures is specifically described as being utilized with a series of interconnected hazardous condition detectors, it should be understood that the relay module 28 could be utilized in various other situations in which the mode of operation of the relay module 28 can be selected from one of a plurality of modes of operation. In other applications, the control unit 48 selects the mode of operation based upon the state of the selection signal present at the selection input 62. As described, the state of the selection signal depends upon the connection between the selection wire 64 and either the neutral line 24 or the power supply line 22. The third state of the selection signal is the floating state indicated when the selection wire 64 is left unconnected.
As described above, the control unit 48 receives two separate inputs, namely the selection signal and the interconnect signal, and interprets these signals to selectively control the movement of the movable contact 54 within the relay unit 50.
Referring back to
Finally, when the selection wire 64 is connected to the neutral line 24, the microcontroller of the control unit 48 is programmed to operate in a third mode and respond to either the smoke or carbon monoxide alarm signals. Thus, the control unit will generate the control signal along control line 52 upon a high level at either the first control line 58, indicating the presence of the first sensed condition or a high signal along the second control line 60, indicating the presence of the second sensed condition.
As can be understood above, the microcontroller of the control unit 48 is programmed to selectively respond to either the first sensed condition, the second sensed condition or the presence of either one of the first and second sensed conditions based upon the state of the selection input 62. The state of the selection input is determined by whether the selection wire 64 is connected to either the hot, power line 22, the neutral line 24 or is left unconnected to either the power line 22 or the neutral line 24. The microcontroller of the control unit 48 detects the state of the selection input and is programmed to operate in one of three modes and to respond by generating a control signal along line 52 to control the movement of the relay unit 50 based upon the state of the selection signal. Thus, by selectively coupling the selection wire 64 to one of three states, a user can provide a control input to the control unit 48 to select how the control unit 48 will respond to the signal along the interconnect line 26.
Although the present invention has been shown and described with reference to a relay module interconnected within a network of hazardous condition detectors, it should be understood that the relay module 28 could be used in various other applications in which an informational signal is received by the relay module and the relay module selectively responds depending upon the value of the informational signal. The use of the selection wire 64 to determine the mode of operation of the control unit 48 allows the single relay module 28 to be utilized with various different types of situations that can be identified by the value of the interconnect signal.