Power distribution using a network of public communications and power

Abstract

A network power distribution system (300) using a common communication and power line includes a power line (314), a plurality of fire alarm units, and a power line control device (302). The power line (314) provides alternating current, and the fire alarm units are coupled to the power line (314). The power line control device (302) is coupled to the power line (314) and to a particular fire alarm unit of the plurality of fire alarm units. The power line control device (302) includes a communication translator (304) to convert between the power line (314) and a non-power line protocol, and a power line core (306) to modulate signals to and from the power line (314).

Description

Technical Field

[0001] The present application relates to the field of building management systems, and more particularly to a network power distribution for a fire alarm system. Background Art

[0002] Traditional fire alarm systems require dedicated communication and power lines for fire alarm control to ensure proper operation. For paths between panels and between panels and devices, separate physical connections for communication and power lines are often required. Communication lines include dedicated communication networks with different communication channels using various protocols, typically serial communication (such as RS485 or RS232) over twisted-pair copper wire, Ethernet, fiber optics, or wireless. Current single-pair copper solutions still require AC power.

[0003] State and municipal governments have adopted the National Fire Alarm and Signaling Code (NFPA 72) as their standard for implementing and managing fire detection, signaling, and emergency communications for fire alarm systems. NFPA 72 specifies a classification of signal paths used in fire alarm systems to ensure reliable, repairable, and sustainable operation. Of particular note are NFPA 72 Class A and Class X, which specify redundant signal paths to reduce operational interruptions in the event of an outage and continuous communication, including indication of any problems. Additionally, similar to the other classes, NFPA 72 Class B requires detection of error conditions in the event of a line fault.

[0004] Wireless technology can be used to reduce the amount of physical wiring required for fire alarm systems. However, wireless communication is only considered a Class N solution and therefore cannot be offered as a Class N solution compliant with NFPA 72, which includes Classes A and X. Consequently, some fire jurisdictions will not allow wireless. Even if a wireless solution is implemented, some jurisdictions still require a dedicated AC mains connection for the fire alarm system. Summary of the Invention

[0005] According to one embodiment of the present disclosure, a common linear power supply and communication method for fire alarm systems is provided. This method allows users to establish multi-node and / or multi-responder fire control systems without requiring wired connections other than power lines or any form of wireless communication. Fire panel devices can be connected together via a dedicated power mains, eliminating the need for any additional wiring for fire and fire voice communications. In a sense, this method simplifies traditional systems, providing cost savings during installation, for example.

[0006] One aspect is a network power distribution system utilizing public communications and electricity, comprising a power line, multiple fire alarm units, and a power line control device. The power line provides alternating current (AC). The fire alarm units are coupled to the power line. The power line control device is coupled to the power line and to a specific fire alarm unit among the multiple fire alarm units. The power line control device comprises a communication translator and a power line core. The communication translator converts fire alarm communications between a power line protocol and one or more non-power line protocols. The communication translator also provides fire alarm communications in a non-power line protocol to the specific fire alarm unit. The power line core modulates the fire alarm communications from the communication translator in a power line protocol and provides an outgoing power line signal to the power line. The power line core also demodulates the incoming power line signal from the power line and provides the fire alarm communications in a power line protocol to the communication translator.

[0007] Another aspect is a power line control device for a network power distribution system utilizing public communications and power. The power line control device includes an I / O assembly, a communication translator, and a power line core. The I / O assembly is coupled to a non-power communication line and a power line. The non-power communication line transmits fire alarm communications, while the power line transmits alternating current (AC) and fire alarm communications. The communication translator converts fire alarm communications between a power line protocol and one or more non-power line protocols. The communication translator also provides fire alarm communications in a non-power line protocol over the communication line. The power line core modulates the fire alarm communications from the communication translator in a power line protocol and provides an outgoing power line signal to the power line. The power line core also demodulates the incoming power line signal from the power line and provides the fire alarm communications in a power line protocol to the communication translator.

[0008] Yet another aspect is a method for controlling a power line device of a network power distribution system using utility communications and power. The method includes receiving alternating current power from a power line. Based on an input power line signal from the power line, a fire alarm communication is generated in a power line protocol. In response to the generation of the fire alarm communication, the fire alarm communication is converted from the power line protocol to one or more non-power line protocols. The fire alarm communication is provided to a non-power communication line in the one or more non-power line protocols.

[0009] The above features and advantages and other features and advantages will become more readily apparent to those skilled in the art by reference to the following detailed description and accompanying drawings. While it is desirable to provide one or more of these or other advantageous features, the teachings disclosed herein extend to those embodiments that fall within the scope of the appended claims, regardless of whether or not they achieve one or more of the above advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, wherein like numerals represent like objects.

[0011] Figure 1 A schematic diagram of a building management system, in an exemplary implementation, operable to employ the techniques described herein is shown.

[0012] Figure 2 A schematic diagram of a fire alarm system, in an exemplary implementation, operable to employ the techniques described herein is shown.

[0013] Figure 3 A schematic diagram of a power line control apparatus operable to employ the techniques described herein in an exemplary implementation is shown.

[0014] Figure 4 A flow diagram illustrating power line control operations in an exemplary implementation operable to employ the techniques described herein is shown. DETAILED DESCRIPTION

[0015] Different technologies related to systems and methods for facilitating common line power and communications will now be described with reference to the accompanying drawings, wherein like reference numerals represent like elements throughout. In this patent document, the drawings discussed below and the various embodiments used to describe the principles of the present disclosure are for illustration only and should not be construed in any way to limit the scope of the present disclosure. Those skilled in the art will understand that the principles of the present disclosure can be implemented in any suitably arranged device. It should be understood that the functions described as being performed by certain system elements can be performed by multiple elements. Similarly, for example, an element can be configured to perform the functions described as being performed by multiple elements. The various innovative teachings of the present application will be described with reference to exemplary non-limiting embodiments.

[0016] Public-line power and communication methods utilize existing power lines to transmit information to fire alarm system panels and devices. For conventional applications, power line communication (PLC) technology exists. For example, HomePlug AV2 is a standard PLC specification that complies with the IEEE 1901 standard and is intended for the residential market. PLC can be used as an alternative to different application protocols in fire alarm systems, but must be adapted to comply with fire safety standards such as NFPA 72.

[0017] The common-line power and communications approach addresses the problem of adapting PLC technology to fire alarm systems. Fire alarm systems communicate via power lines, which are used to connect the power of one fire alarm unit (such as a fire alarm control panel) to the power of the next fire alarm unit via dedicated power lines. The common-line power and communications approach includes NFPA 72-compliant power topology, ground fault detection, and other supervisory and survivability features not addressed by traditional PLC-based communications.

[0018] See also Figure 1, shows a fire alarm system 100 having a networked power distribution system. The fire alarm system 100 includes a communication bus 102 to facilitate communication between various components, such as one or more fire alarm control panels 104 and associated devices. The fire alarm control panel 104 is a device that identifies fire-related hazards based on data received from fire-related input devices and manages fire-related output devices based on the identified fire-related hazards.

[0019] The fire alarm system 100 can also include other components, such as one or more management devices 106 of the system or external devices 108 that can communicate indirectly with system components via a communication network 110. The management devices 106 (such as workstations and / or servers) set and / or change the functionality of various components that communicate with other system devices (such as the fire alarm control panel 104). Examples of external devices include, but are not limited to, remote terminals for receiving, providing, exchanging, or analyzing data related to fire-related hazards. Although a brief description of the fire alarm system 100 is provided below, it should be understood that the fire alarm system described herein is merely one example of a specific form or configuration of a fire alarm system, and that the system can be implemented in any other suitable manner without departing from the scope of the present disclosure.

[0020] for Figure 1 In the illustrated embodiment, the communication bus 102 provides connectivity to subsystems for various fire safety parameters. For example, each fire alarm control panel 104 of the fire alarm system 100 is capable of communicating via the communication bus 102 with various fire-related devices, such as an initiating device circuit (IDC) device 112, a notification appliance circuit ("NAC") device 114, and a fire alarm relay device 116, for monitoring and controlling the fire alarm environment within a commercial or residential facility. Examples of IDC devices 112 include, but are not limited to, smoke detectors 118, temperature detectors 120, air duct devices 122, input / output modules 124, and pull-type fire alarm boxes 126. The NAC device 114 notifies facility occupants of a fire or other life-threatening emergency. The NAC is a solid-wire loop that provides power to the NAC device 114, thus monitoring the wires that make up the circuit, not the device itself. The circuit extends from the fire alarm control panel 104 to the NAC device 114 located within the facility, which is connected by a solid-wire loop. Examples of NAC devices include, but are not limited to, flashing lights 128, horns 130, chimes, bells 132, electric horns 134, and speakers 136. Fire alarm relay devices 116 are similar to NAC devices 114, but require more management than just power control, such as speakers that require audio signals to provide dynamic sounds and notifications. It should be understood that the fire alarm system 100 can include any suitable number of any of the components 112-142 based on the specific configuration of each facility or group of facilities.

[0021] For some embodiments, the fire alarm system 100 can include one or more responders 144, 146 for connecting fire-related devices 118-126, 138-142, 150-154 to a specific fire alarm control panel 104. Each responder 144, 146 can communicate with the fire alarm control panel 104 and a plurality of wired or wireless devices. For example, the fire alarm system 100 can include an addressable responder 146 that communicates with the fire alarm control panel 104 and a plurality of devices 138-142, 150-154 via a communication protocol specific to the fire alarm control panel.

[0022] See also Figure 2 , shows a network power distribution system of a fire alarm system 200 having a plurality of fire alarm units 202-206 and a power line control device (PLCD) 208-212 corresponding to each fire alarm unit. Each power line control device 208-212 can be included inside the housing of the corresponding fire alarm unit 202-206 or accompanied externally. Each fire alarm unit 202-206 includes an operating unit 214-218 configured to control the operation of the fire alarm unit and a power supply unit 220-224 configured to receive power. Examples of fire alarm units include, but are not limited to, fire alarm control panels, fire alarm responders, fire alarm detection devices, and fire alarm notification devices. For some embodiments, for reliability purposes, each fire alarm unit 202-206 can be associated with multiple power line control devices 208-212, 228-232 to achieve redundancy. For some embodiments, each fire alarm unit 202-206 may be associated with a plurality of power line control devices 208-212, 228-232 to provide communications to devices associated with a particular fire alarm unit, such as responders associated with a particular fire alarm control panel.

[0023] Power can be provided to the fire alarm units 202-206 in more than one manner. For some embodiments, each power supply unit 220-224 can receive power from a power source (such as the main AC power source 226) and provide power to the corresponding operating unit 214-218. For some embodiments, the power line control devices 208-212, 228-232 can manage power to the fire alarm units 202-206 by receiving power from a power source (such as the main AC power source 226) and providing power to the corresponding operating unit 214-218. Thus, each power supply unit 220-224 can receive power from one or more corresponding power line control devices 208-212, 228-232 and provide power to the corresponding operating unit 214-218, thereby eliminating the need for a direct connection between the power supply unit and the power source.

[0024] The network power distribution system of the fire alarm system 100 provides common line power and communications to each fire alarm unit 202-206 via corresponding power line control devices 208-212. Thus, a common line 234 couples between the main AC power source 226 and each power line control device 208-212, as well as between the individual power line control devices. Furthermore, for some embodiments, each power line control device 208-212 provides communications and power to its corresponding fire alarm unit 202-206. In contrast, conventional systems utilize separate lines for powering and controlling each fire alarm unit, and utilize multiple wires for powering, controlling, and communicating with each unit. Accordingly, each fire alarm unit 202, 206 receives AC power to power its operating elements 214-218, and each fire alarm unit sends and receives communication signals encoded or encrypted in the AC power via its corresponding power line control device 208-212 to communicate with its operating elements.

[0025] In some embodiments, the network power distribution system of the fire alarm system 100 includes multiple common lines 234, 236 for redundancy, to increase system reliability and comply with applicable laws and regulations. For example, to comply with Class A and / or Class X of NFPA 72, the output and return paths for Class A and Class X must be separate and distinct. Thus, a first power line 234 provides AC power to each fire alarm unit 202-206 and its corresponding power line control device 208-212, and a second power line 236 redundantly provides AC power to each fire alarm unit and its corresponding power line control device. The independent and distinct power lines 234, 236 can be supplied by independent and distinct secondary AC power sources 238, 240 coupled to the primary AC power source 226.

[0026] Networked power distribution systems are also suitable for fire alarm systems that include both single and multiple utility lines. Multiple nodes or responders can be installed without requiring wired connections between endpoints other than power. For example, the AC mains can be used to connect fire panel equipment together for fire and fire voice communications without requiring any additional wiring. Networked power distribution systems will comply with NFPA 72 Class B and other categories, which require detection of fault conditions in the event of a line fault (such as a single open or shorted wire).

[0027] See also Figure 3 , shows a power line control device (PLCD) 302 of a fire alarm system. Specifically, Figure 3 A power line control device 302 of a network power distribution system 300 using utility communications and power is shown. The power line control device 302 includes a communication translator 304, a power line core 306, and input / output components (VO components) 308, 310 coupled to a non-power communication line 312 and at least one power line 314. The I / O components 308, 310 include a first I / O component 308 coupled to the non-power communication line 312 that provides a network communication connection. The I / O components 308, 310 include a second I / O component 310 coupled to the power line 314 that provides an AC power connection. As described above, Figure 2 As described, for some embodiments, the power lines 314 coupled to the second I / O component 310 can include a first power line 314A and a second power line 314B, wherein each of the first power line and the second power line provides an AC power connection.

[0028] Non-power communication line 312 transmits fire alarm communications, while power line 314 transmits alternating current (AC) and fire alarm communications. For some embodiments, power line 314 may include alternating current (AC) that provides power to power line control device 302 and acts as a carrier signal for transmitting fire alarm communications. Thus, the carrier signal can be modulated with the communication signal carrying the fire alarm communications, and similarly, the communication signal can be demodulated from the carrier signal. In contrast, in terms of its usefulness (when providing power to any particular device), non-power communication line 312 is a network communication line used to transmit fire alarm communications (in a format different from that of power line 314). For some embodiments, the communication signals carried by non-power communication line 312 may include one or more signals based on Arcnet, BACnet, Controller Area Network, Ethernet, or a proprietary fire alarm protocol. Thus, one or more non-power line protocols can provide communications to at least one of a fire alarm control panel, a fire alarm responder, an initiator circuit, a notification device circuit, or a relay circuit.

[0029] The communication translator 304 includes a physical media adapter to translate information back and forth between the associated operating unit and the powerline core 306 by converting media and protocol formats between them. The communication translator 304 converts fire alarm communications between the powerline protocol and one or more non-powerline protocols. For fire alarm communications input to the first I / O component 308 from the non-powerline communication line 312, the communication translator 304 converts the communications from the non-powerline protocol to the powerline protocol and provides the converted communications to the powerline core 306. For fire alarm communications input from the powerline core 306, the communication translator 304 converts the processed communications from the powerline protocol to the non-powerline protocol and provides the converted communications to the non-powerline communication line 312 via the second I / O component 310. In some embodiments, the communication translator converts the fire alarm communications to at least one of Arcnet, BACnet, Controller Area Network, Ethernet, or a proprietary fire alarm protocol. In some embodiments, the fire alarm communications are data packets, where each packet includes a header indicating one or more of the following: a source address, a destination address, and a message type. For example, the message type can be a global message in which the receiver does not need to respond or a specific message in which the device addressed by the message needs to respond. For some embodiments, each packet can be addressed to one or more specific devices, but received by non-addressed devices, such that the non-addressed devices ignore the received specific packets.

[0030] Power line core 306 utilizes PLC technology to transmit and / or receive data over power lines, particularly AC power lines. Power line core 306 provides output power line signals to power line 314 via second I / O component 314. Specifically, power line core 306 may modulate fire alarm communications received from communication translator 304 in the power line protocol. Power line core 306 may also provide fire alarm communications in the power line protocol to communication translator 304. Specifically, power line core 306 demodulates input power line signals representing AC power from power line 314. For some embodiments, power line core 306 may use a difference frequency superimposed on a carrier signal to group data destined for multiple devices together for communication with other power line control devices 302.

[0031] As above see Figure 2For some embodiments, the power line control device 302 can manage power for the fire alarm units by receiving power from a power source at a second I / O component 310 and providing the power to the corresponding operating units of the fire alarm units. Independent of the first I / O component 308 and the non-power communication line 312, these embodiments of the power line control device 302 can include a third I / O component 316 to provide power to the fire alarm units via a PLCD power line 318. By providing power to the fire alarm units via the power line control device 302, each power line control device manages the power and functionality of the corresponding fire alarm unit. It should be noted that the non-power communication line 312 and the PLCD power line 318 can be physically separate from each other or physically combined when operating separately.

[0032] In addition to the communication translator 304 and the power line core 306, the power line control device 302 may include a ground fault detection circuit. The ground fault detection circuit detects, manages, and reports ground faults to a fire alarm unit coupled to the power line control device 302. The ground fault detection circuit 320 monitors for a first ground fault, as a subsequent ground fault will cause an alarm condition. The ground fault detection circuit 320 distinguishes between a ground fault and an alarm by measuring the current in the communication line.

[0033] For some embodiments, the power line control device 302 can further include configuration, storage, and / or diagnostic circuitry 322. The configuration storage and diagnostic circuitry 322 can perform various operations to set up and maintain proper operation of the device.

[0034] See also Figure 4 , a flow chart depicting a method 400 for a power line control device 302 of a network power distribution system using utility communication and power is shown. The power line control device 302 receives alternating current (AC) from a power line (PL) from a power line 314 connected to a second I / O component 310 (402). The power line control device 302 then generates a first alarm communication (404) in a power line protocol based on an input power line signal of the power line. For example, the power line control device 302 can generate a fire alarm communication (406) in a power line protocol by demodulating the input power line signal from the AC power of the power line.

[0035] In response to generating a fire alarm communication (404), the power line control device 302 converts the fire alarm communication from a power line protocol to one or more non-power line protocols (408). For some embodiments, the power line control device 302 can convert the fire alarm communication to one or more of Arcnet, BACnet, a controller area network, Ethernet, or a proprietary fire alarm protocol. For some embodiments, at least one non-power line protocol can provide communications to one or more of a fire alarm control panel, a fire alarm responder, an initiator circuit, a notification device circuit, or a relay circuit. The power line control device 302 provides the fire alarm communication in the non-power line protocol to a non-power communication line (CL) (410). For some embodiments, the power line control device 302 can provide the output power line signal to the power line by modulating the output power line signal to the alternating current of the power line 314.

[0036] See also Figure 4 , the method 400 for the power line control device 302 of the network power distribution system can also (or alternatively) process communications input from the fire alarm unit to the power line 314. Specifically, the power line control device 302 receives a second fire alarm communication in a non-power line protocol from the non-power line communication line (412). Then, in response to receiving the second fire alarm communication (412), the power line control device 302 converts the second fire alarm communication from the non-power line protocol to the power line protocol (414). Next, the power line control device 302 generates an output power line signal (416) based on the second fire alarm communication in the power line protocol. The power line control device 302 provides the output power line signal to the power line (418). For example, the power line core 306 of the power line control device 302 can modulate the output power line signal into alternating current (420) of the power line 314.

[0037] Those skilled in the art will recognize that, for the sake of simplicity and clarity, the complete structure and operation of all data processing systems suitable for use with the present disclosure are not depicted or described herein. Furthermore, no feature or process described herein should be considered essential to any or all embodiments except as described herein. In various embodiments, different features can be omitted or duplicated. The various processes described can be omitted, repeated, performed sequentially, simultaneously, or in a different order. Various features and processes described herein can be combined in other embodiments as described in the claims.

[0038] It is important to note that while the present disclosure includes a description in the context of a fully functional system, those skilled in the art will appreciate that at least portions of the mechanisms of the present disclosure can be distributed in any of a variety of forms in the form of instructions embodied in a machine-usable, computer-usable, or computer-readable medium, and that the present disclosure applies equally regardless of the specific type of instruction or signal-bearing medium or storage medium used to actually perform the distribution. Examples of machine-usable / readable or computer-usable / readable media include: non-volatile, hard-coded media such as read-only memory (ROM) or erasable, electrically programmable read-only memory (EEPROM); and user-recordable media such as floppy disks, hard drives, and compact disk read-only memory (CD-ROM) or digital versatile disks (DVD).

[0039] Although the exemplary embodiments of the present invention have been described in detail, those skilled in the art will understand that they can make various changes, substitutions, alterations, and alterations herein without departing from the spirit and scope of the invention in its broadest form.

Claims

1. A network power distribution system using public communications and electricity, the network power distribution system comprising: a power line providing alternating current, the power line comprising a first power line and a second power line; a plurality of fire alarm units coupled to the power line; a first power line control device coupled to the first power line and a specific fire alarm unit among the plurality of fire alarm units, and a second power line control device coupled to the second power line and a specific fire alarm unit among the plurality of fire alarm units; Each of the first power line control device and the second power line control device includes: a communications translator for converting fire alarm communications between a power line protocol and at least one non-power line protocol and for providing the fire alarm communications in the non-power line protocol to the specific fire alarm unit, wherein at least one of the non-power line protocols comprises at least one of Arcnet, BACnet, or a controller area network; and A power line core for providing an outgoing power line signal to a corresponding power line by modulating the fire alarm communication in the power line protocol from the communication translator, and providing the fire alarm communication in the power line protocol to the communication translator by demodulating an incoming power line signal from the corresponding power line.

2. The network power distribution system according to claim 1, wherein: Each power line control device extracts the fire alarm communication from the alternating current of the power line and provides the fire alarm communication to connect to the network communication with the specific fire alarm unit.

3. The network power distribution system according to claim 1, wherein: The fire alarm unit is at least one of a fire alarm control panel, a fire alarm responder, an initiator circuit, a notification device circuit, or a relay circuit.

4. The network power distribution system according to claim 1, wherein: The power line core demodulates an input power line signal from the alternating current of the power line.

5. The network power distribution system according to claim 1, wherein: The power line core modulates the output power line signal into alternating current (AC) on the power line.

6. A power line control device for a network power distribution system using public communications and electricity, the power line control device comprising: an I / O assembly coupled to a non-power communication line and a power line, the non-power communication line carrying fire alarm communications, and the power line carrying alternating current and the fire alarm communications; a communications translator for converting the fire alarm communications between a power line protocol and at least one non-power line protocol and providing the fire alarm communications in the non-power line protocol using a communications line, wherein the at least one non-power line protocol comprises at least one of Arcnet, BACnet, or a controller area network; and a power line core that provides an outgoing power line signal to the power line by modulating the fire alarm communication in a power line protocol from the communication translator, and provides the fire alarm communication in the power line protocol to the communication translator by demodulating an incoming power line signal from the power line, wherein the power line coupled to the I / O component includes a first power line and a second power line, and The power line control device is a first power line control device of a fire alarm unit coupled to the first power line, and the first power line control device operates in coordination with a second power line control device of a fire alarm unit coupled to the second power line.

7. The power line control device according to claim 6, wherein: The I / O components are coupled to the non-power communication lines that provide a network communication connection.

8. The power line control device according to claim 6, wherein: At least one of the non-powerline protocols provides communications to at least one of a fire alarm control panel, a fire alarm responder, an initiator circuit, a notification device circuit, or a relay circuit.

9. The power line control device according to claim 6, wherein: The power line core demodulates the input power line signal from the alternating current of the power line.

10. The power line control device according to claim 6, wherein: The power line core modulates the output power line signal into alternating current (AC) on the power line.

11. A method for controlling a power line device of a network power distribution system using public communication and power, the method comprising: receiving alternating current from power lines, the power lines comprising a first power line and a second power line; A first power line control device of a fire alarm device operates in cooperation with a second power line control device of a fire alarm device, the first power line control device being coupled to the first power line and the second power line control device being coupled to the second power line, generating a fire alarm communication in a power line protocol based on an input power line signal of the power line; In response to generating the fire alarm communication, converting the fire alarm communication from the power line protocol to at least one non-power line protocol, wherein at least one of the non-power line protocols comprises at least one of Arcnet, BACnet, or a controller area network; and The fire alarm communication in at least one of the non-power line protocols is provided to a non-power communication line.

12. The method according to claim 11, wherein Generating the fire alarm communication in the power line protocol includes demodulating the input power line signal from the alternating current on the power line.

13. The method according to claim 11, wherein At least one of the non-powerline protocols provides communications to at least one of a fire alarm control panel, a fire alarm responder, an initiator circuit, a notification device circuit, or a relay circuit.

14. The method according to claim 11, further comprising receiving from the non-power communication line at least one second fire alarm communication in the non-power line protocol; in response to receiving the second fire alarm communication, converting the second fire alarm communication from at least one of the non-power line protocols to the power line protocol; generating an output power line signal based on the second fire alarm communication in the power line protocol; and The output power line signal is provided to the power line.

15. The method according to claim 11, wherein Providing the output power line signal to the power line includes modulating the output power line signal into alternating current on the power line.

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