The present invention relates in general to the provision of Network Line Power (NLP) for electrical, electronic, and electromechanical applications, and more particularly to providing primary or backup power for an optical network terminal.
There are numerous electrical, electronic or electromechanical systems, such as, for example, a digital subscriber line access multiplexer (DSLAM), repeater, cell tower, and fiber optic network termination for Fiber-to-the-Home (FTTH) which require a highly reliable power supply. FTTH service allows for the provision of high bandwidth connections to a customer's home by means of fiber optic cables used to provide voice, high bandwidth data (e.g., Internet access), and/or multimedia services such as video. Fiber-to-the-Premises (FTTP) may also be used to describe this service as high bandwidth networks are also used to provide service to business customers in office buildings and remote locations, such as warehouses and cell sites. These services may be provided by local exchange carriers (LECs). Further, LECs may provide these services to compete with cable based service providers.
FTTH networks have been offered in new construction (e.g., “Greenfield applications”), where fiber-optic cables are pre-installed at each customer location. Whether the homeowner wishes to make use of this facility may be a question of the competitive nature of the service. This, in turn, is very dependent on the costs of the network termination and its power supply. Some LECs offer FTTH in existing housing developments (e.g., “Brownfield applications”), where fiber optic cable is not normally installed. Fiber optic services may be more difficult to install in existing developments and the service usually competes with existing cable services. As a result, the cost for providing service may be critical to retain customers and/or lure cable customers to FTTH service.
FTTH networks may also service multiple dwelling units (MDUs) which represent about 32% of residential dwellings in certain areas. One difficulty in employing a FTTH for a multiple dwelling unit may be the cost associated to run separate fiber cables to each dwelling unit and supplying each unit with separate power. As a consequence, a single Multi Dwelling Unit (MDU) is used with a single power supply to service a group of dwellings. Similarly, FTTP networks may be used in business establishments having multiple offices sharing a fiber line and/or in remote locations such as cell sites, that also require reliable access to fiber networks.
FTTH service typically requires equipment at a customer premises for detection and conversion of data transmitted over fiber optic cables. The equipment typically requires electrical power for operation. When a power source for the customer premises equipment fails, services and/or data provided over the fiber optic channel may not be retrieved. Further, while video and data are currently considered non-essential services, Federal Communication Commission (FCC) regulations and/or other government agency regulations require a minimum power backup time for equipment to support at least one primary voice line or a so called “Lifeline phone” service to provide voice communication in emergencies even when local power fails. Thus, FTTP and FTTH networks may require a reliable power source to be independent of failure prone power utility sources, or as a backup where the power utility is used as the primary power source.
As such, what is needed is a system for supplying reliable power to a customer premises in order to overcome one or more of the aforementioned drawbacks.
Disclosed and claimed herein are systems and apparatus for providing network line power (NLP). In one embodiment, a network line power termination (NLPT) includes input terminals configured to receive network line power from a network communication line, at least one voltage converter configured to receive the enhanced voltage received from the network communication line to supply DC voltage and output terminals configured to output the converted voltage. The network line power termination is further configured for outputting voltage converted by the voltage converter either as one or more of a primary and a backup power source for a network termination. Other aspects, features, and applications of the invention will be apparent to one skilled in the relevant art in view of the following detailed description of the invention.
The features, objects, and advantages of the present invention will become more apparent from the detailed description set forth below when taken in conjunction with the drawings in which like reference characters identify correspondingly throughout and wherein:
One aspect of the present invention relates to providing network line power (NLP). NLP may allow for electrical, electromechanical or electronic equipment, such as an optical network terminal (ONT) to continue operating in a communications network during a power utility failure. In one embodiment, an ONT converts optical signals and electrical signals used to deliver television, data service (e.g., Internet services), digital telephony and/or media services in general to subscribers for one or more of a residence, apartment, single or multiple dwelling unit, and business location which is offered a fiber optic connection to a digital or analog network. Providing these services by the ONT requires local uninterrupted power. Many ONTs are powered by utility services. However, during a power failure many ONTs fail to operate without power.
To meet the Federal Communication Commission (FCC) regulations and/or other government agency regulations to provide at least one primary voice line or a so called “Lifeline phone” service, power may be supplied to critical systems and components of a network, such as an ONT, by one or more of: 1) a separate local battery backup system (e.g., uninterrupted power supply (UPS) inside a dwelling or structure where service is provided; 2) a UPS on the outside of the dwelling or structure; 3) batteries embedded in an ONT; 4) NLP supplied from a neighborhood UPS; and 5) in accordance with one or more embodiments of the invention, NLP supplied from a central office or remote terminal that includes a battery source and back up charging equipment and/or power generators which operate in emergencies. Further, power supplied to components of a network may be in accordance with regulatory agencies according to another embodiment. Thus, NLP according to the invention may be in accordance with Federal Communication Commission (FCC) regulations and/or other government agency regulations which require a minimum power backup time for equipment to support such primary line or “lifeline” services.
In one embodiment, a backup power system for providing NLP includes a backup power installation, a network line power termination (NLPT) coupled to the network communication line, the NLPT configured to convert the enhanced voltage received from the network communication line to supply DC voltage, and an ONT and/or other power critical equipment electrically coupled to the NLPT and an optical communication medium wherein the ONT is configured to supply one or more communication services for a customer premise. The NLPT can supply DC voltage to the optical network termination as a primary reliable power source or as a backup power source. According to another embodiment, the NLPT may be provided to supply backup power for any equipment requiring a reliable power source.
Although the present disclosure is directed to an ONT, it should be appreciated that the systems and methods described herein may apply to other network components and/or network terminations including a digital subscriber line access multiplexer (DSLAM), repeater, network component configured to receive network line power in general, etc. It should also be appreciated that application of the present disclosure is not limited to an ONT or ONT applications. The systems and methods described herein may be employed to provide a primary and/or backup power source for network components and/or any electronic or electromechanical application by means of a NLPT.
As used herein, the terms “a” or “an” shall mean one or more than one. The term “plurality” shall mean two or more than two. The term “another” is defined as a second or more. The terms “including” and/or “having” are open ended (e.g., comprising). The term “or” as used herein is to be interpreted as inclusive or meaning any one or any combination. Therefore, “A, B or C” means “any of the following: A; B; C; A and B; A and C; B and C; A, B and C”. An exception to this definition will occur only when a combination of elements, functions, steps or acts are in some way inherently mutually exclusive.
Reference throughout this document to “one embodiment”, “certain embodiments”, “an embodiment” or similar term means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of such phrases or in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner on one or more embodiments without limitation.
With reference to
Reliable DC electrical power may be supplied from central office batteries, such as battery banks 1015, to drive an electronic or electromechanical application over 1026 according to one embodiment, or a Fiber-to-the-Home (FTTH) optical network termination (ONT) over connection 1022 according to another embodiment. Battery power installation 1010 may include one or more voltage enhancement units (VEU) 1021. Each VEU may be coupled to battery banks 1015. In an exemplary embodiment, VEU may be fed with DC power at −48 volts over connection 1017.
According to one embodiment, reliable DC electrical power may be supplied by central office batteries, such as battery banks 1015, to drive an electronic or electromechanical application, using a Fiber to the Home (FTTH) Outside Network Termination (ONT). Battery banks 1015 may be continuously charged. Each ONT may require as much as 30 watts or greater at 12 volts DC for operation. At 1000 feet using 22 gauge copper wire (i.e., the most favorable case), un-enhanced −48 volts can only supply 18 watts because of power loss and voltage drop in the cable. Thus, it may be necessary to boost battery supplied −48 volts to a much higher value, in this example ±190 volts DC. The boosted voltage can deliver 460 watts at 1000 feet of 26 gauge wire, but for safety reasons (NE 830) the boosting equipment limits the output power to 90 watts. In that fashion, each VEU 1021 can deliver ±190 volts of enhanced DC voltage to terminal 1022 and/or 1026. Terminals 1022 and 1026 may be coupled to network transmission lines including, but not limited to a copper twisted pair.
Battery power installation 1010 may be configured to supply NLP for one or more applications. Thus, terminal 1026 illustrates the possibility of feeding the line power from a VEU to an application (not shown) other than Fiber to the Home (FTTH). By way of example, NLP may be configured to provide power for communication systems, lighting systems, security systems and/or emergency services.
As shown in
In one embodiment, DC voltage delivered from the NLPT 1033 may be fed over connection 1034 to ONT 1032. ONT 1032 may be configured to detect and/or convert optical signals on connection 1031 to provide one or more of Television services, data services (e.g., Internet access), and digital telephony to the subscribers in dwelling 1030.
ONT 1032 is shown mounted on the external wall of dwelling 1030. As will be described in more detail below with respect to
The conversion of the optically transmitted data into electrical signals (and vice versa) may be performed by ONT 1032 and sometimes an Optical Network Unit (ONU) not shown in
System 1000 may be configured to comply with regulations, such as FCC rules requiring that any voice service offered by the LECs shall survive a power utility failure by a minimum of 8 hours. In certain embodiments, ONT 1032 may include 120 volt AC/DC power converters, with the cost of power being bourn by the subscriber. However, an AC/DC power converter will not supply power to ONT 1032 during a power failure to meet the 8 hour requirement. One advantage of the current invention may be to remove the cost of the supply of power from the LEC, except when the power utility ceases to provide power. As will be described in more detail below with references to
Referring now to
In one exemplary embodiment, VEU 2002 may be configured to generate voltage limited to ±190 volts with respect to ground 2004 for output connections 2010, with a maximum short circuit output current of 260 milliamps. In another embodiment, VEU 2002 may be configured to limit the positively and negatively enhanced voltages and a maximum available short circuit output current to values within at least one safety standard. These values may be specified to meet safety standards UL60950-21, GR-001089-CORE and NEC 830. According to another embodiment, VEU 2002 may be configured to output positively enhanced voltage on a first copper line and negatively enhanced voltage on a second copper line, wherein the first and second copper lines form a twisted pair. VEU 2002 may further be configured to provide continuous power under fault free conditions to one or more NLPTs.
According to another embodiment, ground currents may be monitored for each VEU by means of detecting a ground current greater than a threshold value. In the event a ground fault is detected, the ±190 volt outputs of the affected VEU are disconnected by means of ground fault (GF) 2005 controlled relays 2006. VEU 2002 may be electrically coupled to ground and configured to measure ground currents associated with the enhanced voltage feeds of its output and further configured to detect a ground current in excess of a given value, and disconnect the enhanced voltage outputs and initiate an alarm for system 2001.
Output lines 2010 may be protected from lightning and power surges by means of a protection circuit 2003 consisting of series fuse 2008 in each line, and a parallel voltage dependent breakdown device 2009 having a breakdown voltage greater than the output voltage. For example, 200 volt breakdown voltages may be provided by a series fuse, parallel tricil or similar device having a breakdown voltage above a maximum enhanced voltage received, connected from each line to ground 2004 between the fuse and VEU 2002.
Referring now to
According to one embodiment, inputs to NLPT units 3001 may be protected from lightning and voltage surges by modules 3003 consisting of series fuse 3004 in each line, and a parallel voltage dependent breakdown device 3005 having a breakdown voltage greater than the output. In that fashion, lightning and surge protection circuit may be provided for protecting an NLPT and a load from one or more of lightning and power surges carried by first and second copper lines of copper twisted pair 3002. The lightning and surge protection circuit includes one or more of a series fuse in each line, a parallel Tricil, and device having a breakdown voltage, connected from each line to ground between the fuse and a voltage converter.
In another embodiment, ±190 volts of copper twisted pair 3002 may be balanced with respect to ground by coupling each input line to ground 3010 by high value resistors 3006. The resistors 3006 may have equal values to ensure no consequential unbalanced ground current flows. Resistors 3006 may couple each of the first and second copper lines of copper twisted pair 3002 to ground, such that high value resistors 3006 ensure that ground current in the NLPT is below a value which will trigger a ground fault power cutoff and alarm in the one or more of an associated Central Office and remote terminal VEU.
To ensure that an incorrect connection of the input circuits will not damage converter circuits 3008, diode bridge 3007 is connected between the protection circuits and the actual voltage conversion circuits 3008. Diode bridge 3007 may be coupled between the lightning and surge protection circuit and a voltage converter to ensure correct operation when the first and second copper lines are reversely coupled. Voltage conversion circuits 3008 of NLPT 3003 may be custom designed, or a suitable commercially available DC/DC converter configured to generate the required DC voltage to drive the load 3009 requiring either −12 or −48 volts from a range of input voltages (from an upper value of ±190, down to some lesser values).
Referring now to
In one embodiment, ONT 4003 and NLPT 3001 may be mounted on the outside wall of dwelling 4002. ONT 4003 is configured to provide electrical signals 4009 relating to television, data services (e.g., Internet access), digital telephony and/or power for a load through a wall or boundary of dwelling 4002. ONT 4003 may be configured to provide media services to one or more dwellings.
In certain embodiments, ONT 4003 may be part of the load and an additional short duration power surge required for a ring trip function is supplied from a capacitor 4006 which is charged by NLPT 3001 by means of the capacitor charging circuit 4007. In one embodiment, capacitor charging circuit 4007 consists of a resistor to limit inrush current to capacitor 4006 at start up, bypassed by a diode to allow the capacitor to deliver the required surge current. Capacitor 4006 may be charged by output voltage feeding the ONT 4003, such that the capacitor is configured to provide an additional current surge to service a Ring-trip function of a telephony voice circuit of the ONT 4003. Installation of the capacitor may be performed during or after the installation of ONT 4003. Capacitor 4006 may additionally be configured to provide a continuous power supply during a switch over from AC/DC Power Conversion Unit (APCU) in relation to NLPT 5001 of
According to certain embodiments, each NLPT may be configured to provide emergency backup power to support an AC/DC Power Conversion Unit (APCU) in the event that the AC power utility ceases to provide service or the APCU fails. When two power sources are coupled to a load, it is necessary to isolate the power sources from each other with diodes, or some other method of ensuring only one power source is utilized at a time In one embodiment the APCU is given precedence by using a smaller number of isolating diodes than the NLPT. In another embodiment, a diode in the path from the APCU to the load and relay contacts placed in the path from the NLPT to the load, the diode and relay contacts configured to prevent the APCU and NLPT from supplying the load simultaneously, wherein the relay contacts are further configured to be held open by the voltage from the APCU. In yet another embodiment, a diode in the path from the APCU to the load and a control point in an output voltage converter of the NLPT configured, the diode and control point configured to prevent the APCU and NLPT from supplying the load simultaneously, wherein the control point is further configured to disable the NLPT when the control point is held grounded by a relay contact (e.g., switched contact) operated by the voltage from the APCU. In each of these embodiments, the NLPT units (e.g., NLPT units 3001) may be configured to provide a signal to a network termination to alert a signal recipient that the APCU is no longer providing power according to another embodiment.
Referring now to
Due to lightning and/or a high voltage power cross, it may be possible that incoming AC power leads 5002 could conduct electric surges which could damage NLPT 3001, ONT 4003 and/or a load. Thus, the power switch arrangement of
Referring now to
Referring now to
Referring now to
According to another embodiment, NLPT 1032 may be mounted within the box 8001 as shown in
While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative of and not restrictive on the broad invention, and that this invention not be limited to the specific constructions and arrangements shown and described, since various other modifications may occur to those ordinarily skilled in the art.
This Application claims the benefit of U.S. Provisional Application No. 61/091,104, filed Aug. 22, 2008.
Number | Date | Country | |
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61091104 | Aug 2008 | US |