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WO1999005761A1 - Dispositif de protection contre les surtensions pouvant signaler une panne a distance - Google Patents

Dispositif de protection contre les surtensions pouvant signaler une panne a distance Download PDF

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Publication number
WO1999005761A1
WO1999005761A1 PCT/US1998/015007 US9815007W WO9905761A1 WO 1999005761 A1 WO1999005761 A1 WO 1999005761A1 US 9815007 W US9815007 W US 9815007W WO 9905761 A1 WO9905761 A1 WO 9905761A1
Authority
WO
WIPO (PCT)
Prior art keywords
failure
signaler
indication
remote location
telecommunications system
Prior art date
Application number
PCT/US1998/015007
Other languages
English (en)
Inventor
Glenn Davis
David Poche
Original Assignee
Scientific-Atlanta, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Scientific-Atlanta, Inc. filed Critical Scientific-Atlanta, Inc.
Priority to AU87577/98A priority Critical patent/AU8757798A/en
Publication of WO1999005761A1 publication Critical patent/WO1999005761A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R11/00—Electromechanical arrangements for measuring time integral of electric power or current, e.g. of consumption
    • G01R11/02—Constructional details
    • G01R11/25—Arrangements for indicating or signalling faults
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/02—Details
    • H02H3/04—Details with warning or supervision in addition to disconnection, e.g. for indicating that protective apparatus has functioned
    • H02H3/046—Signalling the blowing of a fuse
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H1/00—Details of emergency protective circuit arrangements
    • H02H1/0061—Details of emergency protective circuit arrangements concerning transmission of signals
    • H02H1/0084—Details of emergency protective circuit arrangements concerning transmission of signals by means of pilot wires or a telephone network; watching of these wires
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/02—Details
    • H02H3/04—Details with warning or supervision in addition to disconnection, e.g. for indicating that protective apparatus has functioned
    • H02H3/042—Details with warning or supervision in addition to disconnection, e.g. for indicating that protective apparatus has functioned combined with means for locating the fault

Definitions

  • the invention concerns systems for indicating failures to remote locations generally and more specifically concerns systems for indicating failure of a surge protector or a fuse to a location which is so remote that it can be economically reached only by means of telecommunications techniques.
  • One use of the invention is to inform an electric company of the failure of a surge protector connected to an electric meter.
  • FIG. 1 Description of the Prior Art: FIG. 1
  • the connection between the electrical power grid and a customer's premises must include some kind of surge protector, that is, a device which protects at least the electric meter on the premises from power surges in the electrical power grid.
  • surge protector a device which protects at least the electric meter on the premises from power surges in the electrical power grid.
  • Surges occur whenever there is arcing within the power grid; the arcing hav many causes, including a malfunction of the power generation or distribution equipment within the power grid itself, lightning strikes on the power grid, or damage to the power grid caused by accidents or inclement weather.
  • the surge protection for electric meters has typically been a simple spark gap to ground: any surge strong enough to damage the electric meter sparks across the gap to ground, rather than going through the electric meter.
  • surge protector 103 diverts the surge to ground line 107 and thereby prevents it from entering either electric meter 109 or power lines to premises 111. In diverting the surge to ground line 107, surge protector 103 thus protects electric meter 109, the wiring in the customer premises, and customer equipment connected to that wiring.
  • surge protectors 103 The chief aim in designing surge protectors 103 has been low cost. Typically, surge protectors have been used which fail when the surge is larger than a threshold value. In failing, the surge protectors still divert the surge to ground line 107, but the failed surge protector offers no protection whatever against succeeding surges. In order to detect that a surge protector has failed, one must visually inspect surge protector 103; typically, a peephole 105 gives visual access to the interior of surge protector 103; as with fuses, a failed surge protector either clouds over the peep hole or can be seen visually to be broken.
  • surge protectors are of course not limited to the connection between the electrical power grid and the customer premises; surge protectors are also employed within the customer premises for tasks such as protecting computer systems. These surge protectors may fail in the same fashion as those employed in electric meters, and various systems have been designed which notify the user of the surge protector of its failure by sounding an audio or visual alarm. See for example Corey, Transient Surge Suppressor with Alarm Signal Circuit, U.S. patent 5,153,806, issued Oct. 6, 1992 (audio alarm) or Misencik, et al., Electrical Surge Suppressor with Dual Indicator Apparatus, U.S. patent 4,912,590, issued Mar. 27, 1990 (LEDs indicate status of surge protector). None of this technology, however, provides any hint of how to notify a remote location of the failure of a surge protector.
  • LEDs are used to indicate which fuse of a set of fuses has blown. See, for example, Greenberg, Blade Terminal Fuses with Integrity Indicator, U.S. patent 4, 499,447, issued Feb. 12, 1985.
  • the fuse arts have further provided techniques for informing a control system that a fuse has blown while isolating the control system from the consequences of the blown fuse.
  • Clark, Status-indicating Current Interrupter, U.S. patent 4,604,613, issued Aug. 5, 1986 discloses a system in which the fuse includes an optical cable through which a remote monitor station continuously transmits a light signal to itself. When the fuse blows, the optical cable is broken and the failure of the monitor station to receive the light signal indicates to the monitor station that the fuse is blown.
  • the object of the invention is achieved by means of apparatus which includes a failure detector that detects failure of the fuse or surge protector by producing a failure indication and a failure signaller that responds to the failure indication by accessing a telecommunications system and signalling the failure to a remote location via the telecommunications system.
  • the failure signaller is electrically isolated from the failure detector, so that the failure signaller is not itself affected by the failure.
  • One way of achieving elecrical isolation is by using an optical signal as the failure indication.
  • the failure signaller signals the failure either by simply dialing a telephone number (the telephone number itself indicates the type of failure to the remote location or by placing a packet with a failure message on a wide-area packet network, either directly or by way of a local-area packet network.
  • FIG. 1 is a schematic drawing of a prior-art electric meter with an add-on surge protector
  • FIG. 2 is a schematic drawing of an electric meter with an add-on surge protector that reports failure to a remote location
  • FIG. 3 is a detailed schematic drawing of a surge protection circuit and failure detector employed in a preferred embodiment
  • FIG. 4 is a block diagram of a first technique for communicating between the failure detector and the remote location
  • FIG. 5 is a block diagram of a second technique for communicating between the failure detector and the remote location.
  • the reference numbers in the drawings have at least three digits. The two rightmost digits are reference numbers within a figure; the digits to the left of those digits are the number of the figure in which the item identified by the reference number first appears. For example, an item with reference number 203 first appears in FIG. 2.
  • FIG. 2 Overview of a Surge Protector which Indicates Failure to a Remote Location: FIG. 2
  • FIG. 2 is an overview of a preferred embodiment of the invention as employed in a surge protector for an electric meter.
  • Electric meter 109 is connected between lines 101 from the electric power grid and lines 111 to the customer premises, and has a surge protector to protect electric meter 109, the premises wiring, and equipment connected to the premises wiring from surges in the electric power grid by directing the surge to ground 107, exactly as described with regard to FIG. 1 above.
  • surge protector 203 is coupled to failure detector 205, which detects failures in surge protector 203 by causing light emitter 207 to emit light.
  • the light emitted by light emitter 207 is detected by light detector 211 in failure signaler 209, which responds to the detected light by sending a failure indication via telecommunications link 214 to remote location 215, indicating that surge protector 203 has failed.
  • the signal contains information from which at a minimum the location of electric meter 109 may be determined.
  • Remote location 215 then informs the electric utility of the failure and the utility may send a crew to replace surge protection system 201.
  • the use of lite emitter 207 together with light detector 211 establishes optical isolation 213 between failure detector 205 and failure signaler 209 and ensures that failure signaler 209 will not be disabled by the surge that damaged surge protector 203.
  • FIG. 2 may be used whenever it is worthwhile to indicate failure of a fuse or surge detector to a remote location; further, the principles of the invention are independent of the techniques used to detect failure of the surge protector or fuse, of the techniques used to indicate the failure to the failure signaler, or of the telecommunications techniques used to provide the failure indication to remote location 215. Any suitable technique may be used to perform any of these functions, and the technique used will depend upon factors such as cost and the environment in which the implementation of system 201 is to function.
  • FIG. 3 Preferred Embodiment of Surge Protector 203 and Failure Detector 205: FIG. 3
  • FIG. 3 shows details of surge protector 203 and failure detector 205 in a preferred embodiment.
  • surge protector 203 contains two metal oxide varistor (MOV) surge protection devices, MOVl and MOV2.
  • MOVl is connected to
  • MOV2 is connected to line LI of lines 101.
  • MOVl is further connected via fuse FI to ground line 107 and MOV2 is similar connected by fuse F2 to ground line 107.
  • Failure detector 205 works by connecting a fuse (FI, F2) in series with each MOV (MOVl, MOV2) and a LED (LED1, LED2) in parallel with each fuse. As long as a fuse is intact, current flows through the fuses and not through the LED connected in parallel with it. A power surge that causes a MOV to fail will also blow the fuse that is connected in series with the MOV. That in turn will cause current to flow through the LED connected in parallel with the MOV, and that will cause the LED to emit light.
  • FI, F2 fuse
  • MOVl MOV2
  • LED LED
  • failure detector 205 includes the following components:
  • resistor Rl connected in parallel to MOVl, and resistor R2, connected in parallel to MOV2;
  • fuse FI connected in series between MOVl and ground line 107
  • fuse F2 connected in series between MOVl and ground line 107
  • resistor R3 connected in series with LED1 and resistor R4. connected in series with LED2;
  • LED light emitting diode
  • Fuse FI and fuse F2 are chosen such that a surge which may cause the MOVs corresponding to the fuses to fail will cause the fuse to blow.
  • Failure detector 205 operates when MOVl is intact as follows: since MOVl is intact, it transmits no current from L2; current flows via Rl and FI to ground 107, and no current flows through LED1, which remains unlit. Failure detector 205 operates in the same fashion when MOV2 is intact, with current flowing via R2 and FI to ground 107 and no current flowing through LED2. When MOVl has failed, it transmits current, but the surge which caused it to fail also caused
  • LED1 and LED 2 thus function as light emitter 207.
  • LED1 or LED2 When either LED1 or LED2 is illuminated, the light output from LED1 or LED 2 is received by light detector 211, which in a preferred embodiment is a photo transistor.
  • the photo transistor responds to the light from LED1 or LED 2 by beginning to conduct, which in turn signals microprocessor 313 that a MOV has failed in meter 109.
  • microprocessor 313 then provides a failure message via telecommunications link 214 to remote location 215.
  • LEDs 1 and 2 together with photo transistor 211 provide optical isolation 213 between failure detector 205 and failure signaler 209 and thereby assure that microprocessor 313, which receives its power ultimately from load lines 111, is not affected by the surge which caused the failure of MOVl or 2.
  • FIG. 4 shows an implementation 209A of failure signaler 209 which employs an autodialer to send an indication of a failure of MOVl or MOV2 via a wired or wireless public switched telephone system to remote location 215.
  • light detector 211 generates a failure signal 401 when LED1 or LED2 is illuminated
  • autodialer 403 responds to the failure signal by automatically dialing a telephone number of remote location 215 on telephone connection 404 to the premises to which meter 109 is attached.
  • the telephone connection may of course be used for purposes other than communication between autodialer 403 and remote location 215.
  • the telephone call is routed by telephone company central office switch 405 which has the ANI and DNI features, that is, switch 405 is capable of signaling protocols which return the telephone number from which the call came (ANI) and the telephone number which is the destination of the call (DNI) to the device which answered the call.
  • ANI telephone number from which the call came
  • DNI telephone number which is the destination of the call
  • the number dialed by autodialer 403 is used in remote location 215 only for calls identifying failure of a surge protector, and consequently, the fact of the call itself indicates the type of failure.
  • remote location 215 uses the ANI protocol to obtain the number of the telco connection to premises 404 and then, as shown at 407-11, applies number 409 to location database 407 to obtain location 411.
  • failure message 413 which indicates to a human attendant at remote location 215 or elsewhere the fact of the failure and its location.
  • autodialer 313 is implemented with microprocessor 313 and a standard telephone dialing interface; microprocessor 313 is programmed to respond to the signal produced by photo transistor 211 when a LED is emitting light by causing the standard telephone dialing interface to dial the number that indicates failure of a surge protector.
  • detectors for other conditions discernible at electric meter 109 can be included in surge protection system 201 and these conditions can be signaled in to remote location 215 in the same way as the failure of a surge protector is signaled. There would of course be a different telephone number for each condition.
  • failure signaller 209 is of course possible.
  • the fact of the phone call itself carries the information needed concerning the failure.
  • the connection established between failure signaler 209 and remote location 215 could be used to carry DTMF tones generated under control of microprocessor 313, and these in turn could provide information from which remote location 215 could determine failure type 415 and location 411.
  • Such an implementation would not require that the telephone connection to premises 404 be connected to a central office switch with ANI and DNI.
  • failure signaler 209 and remote location 215 could include analog modems connected to telecommunications link 214 and failure information generated by microprocessor 313 could be carried in digital form.
  • FIG. 5 Implementation of Failure Signaler 209 in a System for Communication between a Customer Premises and a Utility: FIG. 5
  • failure signaler 209 may be implemented as part of a system of the type disclosed in the above patent application.
  • FIG. 5 shows a failure signaler 209B which is so implemented.
  • light detector 211 responds to illumination of LED1 or LED 2 by generating failure signal 401, which is received by microprocessor 313.
  • Microprocessor 313 has access to a memory 501 which contains a surge protector failure program (SPFP) 507 which is executed by microprocessor 313 in response to failure signal 401.
  • SPFP 507 causes microprocessor 313 to generate failure information 510, place it in a local area network (LAN) packet addressed to LAN/WAN interface 515, and outputs the packet to LAN 509.
  • LAN local area network
  • Failure information 510 contains at a minimum a failure identifier 511, which specifies the kind of failure, in this case, the failure of the surge protector, a location identifier 513, which identifies the location of the customer premises, and the WAN address of remote location 215.
  • the location identifier 513 may be a network address, for example, an IP address, of microprocessor 313.
  • Interface 515 receives the LAN packet, places the failure information in a WAN packet addressed to remote location 215, and places the packet on WAN 517.
  • WAN 517 may be implemented using any kind of suitable wired or wireless technology.
  • Remote location 215 receives the packet and produces failure message 413 by applying location identifier 513 from the packet to location database 519 to obtain location 411 and failure identifier 511 to failure data base 521 to obtain failure type 415.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Telephonic Communication Services (AREA)

Abstract

Cette invention se rapporte à un appareil et à des procédés de détection d'une panne dans un dispositif de protection de circuit, tel qu'un dispositif de protection contre les surtensions, ledit appareil étant capable de signaler la panne à un opérateur éloigné par l'intermédiaire d'un système de télécommunications. La panne du dispositif de protection de circuit entraîne la panne d'un fusible, qui à son tour active un dispositif électroluminescent qui émet de la lumière. Cette lumière active un phototransistor qui produit un signal à destination d'un organe émetteur de signaux qui émet un signal vers le lieu éloigné par l'intermédiaire du système de télécommunications. Selon une réalisation, le dispositif émetteur de signaux est un composeur automatique de numéros qui appelle le lieu éloigné au moyen d'un numéro de téléphone qui signale la panne du dispositif de protection de circuit. Au niveau dudit lieu éloigné, on utilise les protocoles ANI et DNI pour obtenir le numéro de téléphone appelé, qui indique le type de problème, et le numéro de téléphone appelant, qui indique l'emplacement du problème. D'autres mises en oeuvre du dispositif émetteur de signaux utilisent des tonalités DTMF ou des paquets numériques pour transmettre les informations relatives à la panne. Le paquet numérique peut être communiqué à une personne en un lieu éloigné au moyen d'une ligne téléphonique analogique et de modems ou par l'intermédiaire d'un réseau de transmission numérique. Le réseau téléphonique tout comme le réseau de transmission numérique peuvent être des réseaux filaires ou des réseaux sans fil.
PCT/US1998/015007 1997-07-22 1998-07-21 Dispositif de protection contre les surtensions pouvant signaler une panne a distance WO1999005761A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU87577/98A AU8757798A (en) 1997-07-22 1998-07-21 Surge protectors that indicate failure to a remote location

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US89842897A 1997-07-22 1997-07-22
US08/898,428 1997-07-22
US92261797A 1997-09-03 1997-09-03
US08/922,617 1997-09-03

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WO (1) WO1999005761A1 (fr)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10012736A1 (de) * 2000-03-16 2001-12-20 Peter Herold Verfahren zur Steuerung von elektrischen Anlagen
DE10040706A1 (de) * 2000-08-17 2002-03-07 Exolution Gmbh Anordnung zur automatisierten Abfrage von Kundenverbrauchsdaten und zur Ubermittlung dieser Daten an einen jeweilegen Lieferanten zu Speicher-und Abrechnungszwecken
DE10041250C2 (de) * 2000-08-22 2002-11-07 Majchrzyk Horacek Matthias Steuerungssystem und Verfahren
WO2005104161A1 (fr) * 2004-04-20 2005-11-03 Cooper Technologies Company Système et procédé de transmission sans fil d'indicateurs de l'état de fusibles
US7391299B2 (en) 2004-09-10 2008-06-24 Cooper Technologies Company Circuit protector monitoring and management system user interface method, system and program
US8169331B2 (en) 2004-09-10 2012-05-01 Cooper Technologies Company Circuit protector monitoring assembly
US8823387B1 (en) 2011-03-11 2014-09-02 Electro-Mechanical Corporation Blown fuse detector
CN108683822A (zh) * 2018-07-24 2018-10-19 杨策 电力故障智能拨号器
US10380869B1 (en) 2018-05-02 2019-08-13 North American Power Products, Inc. Surge protector with wireless notification

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0570310A1 (fr) * 1992-05-15 1993-11-18 Societe Industrielle De Materiel Electrique Simel Générateur de signal pour la télé-détection des défauts de fonctionnement des parafoudres montés sur les lignes électriques de distribution
US5378931A (en) * 1993-03-31 1995-01-03 Allen-Bradley Company, Inc. Low leakage fuse blown detection circuit

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0570310A1 (fr) * 1992-05-15 1993-11-18 Societe Industrielle De Materiel Electrique Simel Générateur de signal pour la télé-détection des défauts de fonctionnement des parafoudres montés sur les lignes électriques de distribution
US5378931A (en) * 1993-03-31 1995-01-03 Allen-Bradley Company, Inc. Low leakage fuse blown detection circuit

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10012736A1 (de) * 2000-03-16 2001-12-20 Peter Herold Verfahren zur Steuerung von elektrischen Anlagen
DE10040706A1 (de) * 2000-08-17 2002-03-07 Exolution Gmbh Anordnung zur automatisierten Abfrage von Kundenverbrauchsdaten und zur Ubermittlung dieser Daten an einen jeweilegen Lieferanten zu Speicher-und Abrechnungszwecken
DE10041250C2 (de) * 2000-08-22 2002-11-07 Majchrzyk Horacek Matthias Steuerungssystem und Verfahren
GB2430564B (en) * 2004-04-20 2008-12-17 Cooper Technologies Co Wireless communication fuse state indicator system and method
GB2430564A (en) * 2004-04-20 2007-03-28 Cooper Technologies Co Wireless communication fuse state indicator system and method
JP2007534134A (ja) * 2004-04-20 2007-11-22 クーパー テクノロジーズ カンパニー 無線通信ヒューズ状態インジケータシステム及び方法
US7369029B2 (en) 2004-04-20 2008-05-06 Cooper Technologies Company Wireless communication fuse state indicator system and method
ES2321364B1 (es) * 2004-04-20 2010-04-08 Cooper Technologies Company "sistema y metodo inalambrico de comunicacion de indicador de estado dde fusible".
WO2005104161A1 (fr) * 2004-04-20 2005-11-03 Cooper Technologies Company Système et procédé de transmission sans fil d'indicateurs de l'état de fusibles
ES2321364A1 (es) * 2004-04-20 2009-06-04 Cooper Technologies Company "sistema y metodo inalambrico de comunicacion de indicador de estado dde fusible".
US7576635B2 (en) 2004-09-10 2009-08-18 Cooper Technologies Company Circuit protector signal transmission, methods and system
US7612654B2 (en) 2004-09-10 2009-11-03 Cooper Technologies Company System and method for circuit protector monitoring and management
US7391299B2 (en) 2004-09-10 2008-06-24 Cooper Technologies Company Circuit protector monitoring and management system user interface method, system and program
US8059005B2 (en) 2004-09-10 2011-11-15 Cooper Technologies Company Circuit protector monitoring assembly kit and method
US8169331B2 (en) 2004-09-10 2012-05-01 Cooper Technologies Company Circuit protector monitoring assembly
US8823387B1 (en) 2011-03-11 2014-09-02 Electro-Mechanical Corporation Blown fuse detector
US10380869B1 (en) 2018-05-02 2019-08-13 North American Power Products, Inc. Surge protector with wireless notification
CN108683822A (zh) * 2018-07-24 2018-10-19 杨策 电力故障智能拨号器
CN108683822B (zh) * 2018-07-24 2024-04-12 杨策 电力故障智能拨号器

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