DEVICE FOR DETECTION OF PROHIBITED OPERATION OF A MEASUREMENT EQUIPMENT

Abstract: A device for an unauthorized power utilization proof electricity meter equipment and detection of unauthorized tampering in the electricity meter equipment, to be used when supplying power to a consumer, such as houses and industries, which device includes a shunt for controlling a number of detection means (A1, A2, A3, A4, 16, 17, 20, 23) arranged before a main fuse (2), which in turn control breaking units (10, 13, 14, 35; 11, 27; 18, 28; 21, 29; 24, 30) and/or alarm unit. The detection means (A1, A2, A3, A4, 16, 17, 20, 23) and the possible breaking units (10, 13, 14, 35; 11, 27; 18, 28; 21, 29; 24, 30) are provided substantially connected to all parts included in the electricity meter equipment, significant for the power supply to the consumer.

Description: Device for detection of prohibited operation of a measurement equipment. TECHNICAL FIELD The present invention refers to a device for a unauthorized power use proof electricity meter equipment and detection of unauthorized tampering of electricity meter equipment, to be used when supplying electricity to a consumer, such as houses and industries, which device includes a power shunt lead arranged prior to a main fuse for conducting a number of detection means, which in turn control switching units and/or alarm means. The object of the present invention is to provide a possibility to deal with unauthorized power usage from main, i.e. stealing power from the main without correct registration of the usage is effected. BACKGROUND OF THE INVENTION Unauthorized power utilization (electricity stealing) is today a relatively great problem, and costs for a medium-sized municipality it can be calculated to be 2-3 millions of crowns per year, which costs frequently affect remaining consumers within a mains region. A unauthorized power utilization is normally not conducted during the entire year, but only during some periods, when one does not expect the visit of a controller. Rationalization within the energy administration has lead to charging procedures after calculated consumption, with one read-out per year, which read¬ out can normally be foreseen. A unauthorized electricity utilization can be done in different ways, the most common is that one in some way hinders the rotation of the meter, either by dismounting the meter from the wall and letting it hang upside down, or by drilling a small hole in the inspection glass and then by means of a steel wire stopping the meter disc. A unauthorized electricity utilization can also be done through infringe in the main circuit before the meter, by turning the phases to counteract the meter equipment, and in many other essentially sophisticated ways. Other unauthorized actions are to fuse up, i.e. to increase included electricity supply possibility from, for example 16A to 25A, where different subscription grades are applied. Thus, there exists a requirement from the power suppliers' side to solve this problem. There are a number of methods to discover shunting, i.e. current by-passing at the electricity meter equipment, for example by branch connection parallel with the electricity meter equipment. Devices and methods for detection of by-pass connection are known, for example through US 5,227,668, EP-Al -0 034 031, EP-A1-0 084 634. These documents describe different methods for sensing current shunting using complicated solutions. These documents give only solution to one problem, while no satisfactory solutions for other occurring unauthorized tampering, which frequently occur are presented. DESCRIPTION OF THE PRESENT INVENTION It has now surprisingly turned out a possibility to be able to solve these problems through the present invention which is characterized in that detection means and possible switching units are arranged, primarily connected to all parts included in the electricity meter equipment, which are significant for power supply to the consumer. The present invention prevents tampering behind plate in the electricity meter cabinet, as well as tampering behind the meter terminal lock, and the meter cover. Moreover, fuse-up of a main fuse, tipping of the electricity meter and damaging of the meter cover are prevented. The present invention will be detailed more closely below, with reference to a preferred embodiment, which is also illustrated in the enclosed drawing, in which FIG. 1 is a wiring diagram for a preferred embodiment of the invention; FIG. 2 shows a form of a protected fuse; FIG. 3 is a frontal view of a meter cabinet; FIG. 4 illustrates a sealed screw to be used in a construction according to the invention; and FIG. 5 shows a cabinet for main switch/main fuses according to the invention. Shown in FIG. 1 is a transformer 1 with battery charger and accumulator located before the main fuses 2 and main switch 3 connected to the incoming main circuit 4. Before the transformer 1, a precision fuse 5 is also connected. The transformer transforms the 220 V voltage, for example down to 12 V to provide for a low voltage system. The ± side of the transformer is connected to a time relay 8 via a resetting switch 6 and a start loop 7 to enable a final connection of the security system. The time relay 8 controls a contact-breaker 32, which conducts the current via a light emitting diode 9, indicating that the alarm is functioning. Hereby, also the left hand (in the drawing) consisting of a series of sensors and switches, is activated. Al, A2, A3 and A4 refer to a series of miniature switches coimected in different positions in the meter cabinet or its corresponding parts, which partly via an integrated circuit 10 (for example TTL 7432 with "OR" gate), partly via a relay 11 with corresponding alarm LED 12 can actuate a switch 27 to close. The integrated circuit 10 is connected to a relay 13, which partly activates switch 14, placed in the input main circuit to break the entire power supply to the meter 15, partly a switch 35 for closing the above left side. Further, a mercury breaker 16 or motion detector 17 should be connected partly over said integrated circuit 10, partly over a relay 18 with corresponding alarm LED 19. A toggle switch 20 is also arranged coimected on the left side, which toggle switch 20 is partly connected via said integrated circuit, partly via a relay 21 and an alarm LED 22. Further, in similar way, a magnetic switch 23 is connected via said integrated circuit 10, partly via a relay 24 and an alarm LED 26. Miniature switches Al, A2, A3 and A4 are suitably placed behind sealed screws 25, which partly hold the glass of the meter 15 in place, partly hold a terminal box lock 33 in place. If a sealed screw 25 is released the miniature switch, for example Al, will break the current flow and a current is conducted through the integrated circuit 10 and further to the relay 13, which breaks the current by means of the open breakers 14 and closed contact-breakers 35. Accordingly, no current is supplied to the meter and thereby not to the internal network, at the same time that the conduction of the switch results in that the integrated circuit permanently receives current, even if the miniature switch is reopened/rebroken. Similarly, a mercury breaker 16 or a motion detector 17 is connected to detect that the meter is not relocated, i.e. hung down. Should the meter be dislocated/moved, or the glass of the meter or cover damaged, the mercury breaker 16 or motion detector 17 generates a signal which conducts current, partly through the integrated circuit 10, partly through the relay 18 whereby relay 13 conducts and breakers 14 break the main power supply and the contact-breaker 35 conducts. Correspondingly, a toggle switch 20 may be located, for example behind the main fuses, whereby a change in the fitting 31 of the main fuses is detected. The toggle switch 20 accordingly provides a current conduction through the integrated circuit 10 and through the relay 21, whereby the switch 29 is closed. In same way, the magnetic switch 23, for example placed behind the cover of main fuses 2 and main switch 3 operates, so if the cover is removed, current is conducted and the relay 13 actuates the contact-breakers 14 to break and the breaker 35 to conduct. The reason of protection of the main fuses 2 is to prevent upgrading through inserting new fuse sockets or conducting current through the fuse. Accordingly, the fuses should be of automatic type. The relays 11, 18, 21 and 24 actuate permanent switches 27, 28, 29 and 30 to prevent a restoration, for example through reinstalling a sealed screw 25. The toggle switch 20 on the fittings 31 of the main fuses can advantageously be replaced with a thermal excess current protection (not shown), which is mounted on/near by the contactor inside the meter or the meter terminal box lock. Said excess current protection is arranged to depend on the consumers main fuse size plus about 10%. If the main fuse should be upgraded, it is changed because of the heat developed due to the current passing through the fuse. This change is detected by thermal excess current protection, functioning as the current switch 20 and breaks the current. Said thermal excess current protection can also be provided with means to be sat in manual or automatic restoring mode. The precision fuse transformer with the battery charger and accumulator 1 is suitably placed in an end portion of the meter 15, remaining parts except the relay 13 are arranged on a printed circuit allowing easy modification and expand of the alarm functions. The relay 13 is placed in another place in the meter and the alarm, i.e. the different contact-breakers, sensors and other indicators are quite naturally placed externally. The resetting button is located so that only trained personnel can access it, for example behind the printed circuit. The printed circuit can in turn be protected against inspection by covering the same with a non conducting hard mass, for example epoxy mass. If somebody should try to break the seal and screw off the meter terminal box lock, the current is conducted via the miniature switches Al, A2, A3 and A4, which implies that the integrated circuit activates the relay 13. The alarm LED 12 is turned on at the same time to indicate the place of the conduction. The relay 11 also actuates the contact-breaker 27, so that a permanent conduction is achieved, even if the screw is screwed back and the miniature switch Al breaks the current. As supplement to the alarm functions the meter cover should be made opaque. A translucent or inspectionable meter cover means that studying the structural design of the meters is very simple and thereby be able to carry out illegal actions. Generally, the device according to invention operates so that the miniature switches Al, A2, A3 and A4 are placed in the electricity meter in holes for sealed screws 25, and when the screw 25 is screwed in place, the contact in the switch is broken, the mercury breaker 16 and motion detector 17 detect if the meter 15 hangs. At normal mounting, the contacts are broken. The toggle switches 20 in the holders of the main fuses, as well as the contact through the magnetic switch(es) 23 are broken. As soon as a tamper takes place in some form, the current is conducted and the main relay 13 breaks the entire current. When connecting, primary the entire device with corresponding alarm is assembled, whereby finally a start loop 7 is connected in time relay 8 circuit. The time relay 8 has such a delay time, for example 5 minutes, that final closing of the meter 15 can be carried out without a problem. When the time relay 8 conducts, the breaker 32 closes the circuit through the LED 9 and indicates that the alarm is activated. If the alarm function is started, the relay 13 actuates the contact- breakers 14 to break and the breaker 35 to conduct. When the resetting switch 6 is hidden in the system, an resetting results in that trained personnel must work with the system. To increase the protection, a timer may be used connected parallel over the contactor 13 or replace the same (not shown). In this case, in normal operation the timer is not activated but at unauthorized tampering the timer is activated. Such a construction implies that authorized personnel can partly retrieve which type of unauthorized tampering was committed (by means of the LEDs 12, 19, 22, 26) and partly when. The battery function in the in line should manage a power failure in a normal case for 24 hours without the alarm functions of the system being activated. If there should be a risk for longer power failure periods, a battery backup having longer life time may be added, for example in remote districts with many aerial lines. As an alternative to an ordinary charger unit, a so called "supercap", which is a capacitor with extremely long discharge time, may advantageously be used to provide the alarm unit with power during long period of possible power failure. In FIG. 2 an automatic main fuse 36 with a fitting 31 and a toggle switch 20, as well as a fuse holder 37 are shown. FIG 3 shows a meter 15 with a terminal box lock 33, which protects connections for enclosed main circuits to the meter, as well as the connections for subscribers power-pack. The glass of the meter 15 is connected to the meter with sealed screws 25, which are shown in detail in FIG. 4 with attached miniature switches Al. In FIG. 5 a covering sheet cover 38 for main switch 3 and main fuses 2 is shown, which cover 38 is worked-up with sealed screws 25 and thereby the cover of the cabinet 38 is provided with a magnetic switch 23, which is arranged to conduct the current if the cover is lifted. While we have illustrated and described a preferred embodiment of the invention, several variations and modifications within the scope of the attached claims may obviously occur, for example the breaking unit can be completed/replaced with LED signal and/or siren signal and/or the alarm can be transmitted to the supplier via a telephone line or the electric supply network. The different breaking and closing units can, for example by means of a computer unit modulating (coding or decoding) signals from/onto the current flowing through the electricity supply network, be connected to the supplier for remote control. To increase the protection, the entire equipment can be arranged under the meter terminal box locket. Reference numeral 1 Transformer 2 Main fuse 3 Main switch 4 Main circuit 5 Precision fuse 6 Resetting switch 7 Start loop 8 Time relay 9 Light emitting diode 10 Integrated circuit 11 Relay 12 Alarm LED 13 Relay 14 Switch 15 Meter 16 Mercury breaker 17 Motion detector 18 Relay 19 Alarm LED 20 Toggle switch 21 Relay 22 Alarm LED 23 Magnetic switch 24 Relay 25 Screw 26 Alarm LED 27 Breaker 28 Breaker 29 Breaker 30 Breaker 31 Main fuse fitting 32 Breaker 33 Terminal box lock 35 Breaker 36 Automatic main fuse 37 Fuse holder 38 Sheet metal cover A1-A4 Switch

Claims: CLAIMS 1. A device for a unauthorized power utilization proof electricity meter equipment and detection of unauthorized tampering in the electricity meter equipment, to be used when supplying power to a consumer, such as houses and industries, which device includes a shunt for controlling a number of detection means (Al, A2, A3, A4, 16, 17, 20, 23) arranged before a main fuse (2), which in turn control breaking units (10, 13, 14, 35; 11, 27; 18, 28; 21, 29; 24, 30) and/or alarm unit, characterised in, that the detection means (Al, A2, A3, A4, 16, 17, 20, 23) and the possible breaking units (10, 13, 14, 35; 11, 27; 18, 28; 21, 29; 24, 30) are provided substantially connected to all parts included in the electricity meter equipment, significant for the power supply to the consumer. 2.restore according to claim 1, characterised in, that miniature switches (Al, A2, A3, A4) are provided connected to the meter (15) and/or connecting the attachment means of the equipment (38). 3. A device according to any one of claims 1-2, characterised in, that a position controlling switch (16) is arranged for detecting the vertical plane position of the meter(15). 4. A device according to any one of claims 1-3, characterised in, that a motion detector (17) is arranged to detect the movements of the meter (15) housing. 5. A device according to any of claims 1-3, characterised in, that a mercury switch (16) is arranged for detecting the movements of the meter (15) housing. 6. A device according to any of claims 1-5, characterised in, that a toggle switch (20) is provided connected to the main fuses (2) of the meter. 7. A device according to any of claims 1-6, characterised in, that a magnetic switch (23) is provided connected the covering of the meter (15) and/or main breaker/main fuses (2,3). 8. A device according to any of claims 1-7, characterised in, that a time dely unit (8) is arranged foi delay of the guard state, for example at start of the device. 9. A device according to any of claims 1-8, characterised in, that a circuit (10) is arranged connected to the detection means for multiplexing the incoming signals. 10. A device according to any of claims 1-9, characterised in, that at least one switch (14) is arranged for breaking the current to the electricity meter equipment at unauthorized tampering, which switch (14) holds its condition until an admitted resetting signal is received. 11. A device according to any of claims 1-10, characterised in, that a timer is provided to be activated at tampering. 12. A device according to any of claims 1-11, characterised in, that the device is connected to a control station for alerting and/or remote control through the electricity main. 13. A device according to any of preceding claims, characterised in, that a thermal protection is provided connected the main fuses (2) of the electricity meter equipment. 14. A device according to any of preceding claims, characterised in, that the device is arranged under the meter terminal box locket.

Inventors: ELGSTROEM MIKAEL, NORDENVIK NILS-OLOF, ELGSTROEM, MIKAEL, NORDENVIK, NILS-OLOF
Applicants: ELGSTROEM MIKAEL, NORDENVIK NILS OLOF, ELGSTROEM, MIKAEL, NORDENVIK, NILS-OLOF
Application year: 1996
Main classification: G01R11
IPC codes: G01R11