AP820A - AC input cell for data acquisition circuits. - Google Patents
AC input cell for data acquisition circuits. Download PDFInfo
- Publication number
- AP820A AP820A APAP/P/1997/001071A AP9701071A AP820A AP 820 A AP820 A AP 820A AP 9701071 A AP9701071 A AP 9701071A AP 820 A AP820 A AP 820A
- Authority
- AP
- ARIPO
- Prior art keywords
- elements
- input
- lines
- voltage
- data acquisition
- Prior art date
Links
- 238000001514 detection method Methods 0.000 description 10
- 239000003990 capacitor Substances 0.000 description 4
- 230000003071 parasitic effect Effects 0.000 description 2
- 239000000470 constituent Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
- G08B29/16—Security signalling or alarm systems, e.g. redundant systems
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
- B61L1/00—Devices along the route controlled by interaction with the vehicle or train
- B61L1/20—Safety arrangements for preventing or indicating malfunction of the device, e.g. by leakage current, by lightning
Landscapes
- Engineering & Computer Science (AREA)
- Computer Security & Cryptography (AREA)
- Automation & Control Theory (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Current Or Voltage (AREA)
- Electronic Switches (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
- Train Traffic Observation, Control, And Security (AREA)
Abstract
An AC input cell for data acquisition circuits, particularly in railway applications. The cell includes at least two lines (A and B) of identical elements, and each line includes at least one Zener diode (T3Z1 or DZ2), an optccouplcr (Ul or L"2) including an LED. a diode (D2 or D4) and a resistor (Rl or R3), each of said elements being arranged in scries.
Description
AC INPUT CELL INTENDED FOR DATA ACQUISITION CIRCUITS.
Subject of the invention.
The present invention relates essentially to an AC input cell intended for data acquisition circuits, more particularly in railway applications.
Technical background.
Currently, AC input cells intended for data acquisition circuits essentially consist of mechanical safety relays which are connected together by simple cabling.
Objects of the invention.
The present invention aims to provide a cell for AC inputs intended for data acquisition circuits, particularly in railway applications, which has at least equivalent behaviour in terms of safety to that of the prior art, while keeping inherent advantages of compactness, easier maintenance and fitting as well as greater longevity.
More particularly, the present invention aims to provide a cell in which misreading always errs on the side of safety.
The present invention also aims to detect malfunctions which may occur in the various constituent elements of the cell.
The present invention furthermore aims to minimize the influence of a variation in the characteristics of the components which are used, under the effect of an external factor such as a rise in temperature, for example.
Principle characteristics of the present invention.
The present . invention relates to an AC input cell intended for data acquisition circuits, comprising at least one device for detecting a voltage greater than the reference for the positive half-cycle at the input voltage, and a device for detecting a voltage greater than the reference for the negative half-cycle of the input voltage.
AP/P/ 9 7 / 0 1 0 7 1
LA
ΑΡ 0.0 0 8 2 0 the present invention, of the two detection
In this case, detection device for
- 2 Each of these detection devices comprises a Zener diode, an optocoupler comprising an emission LED, a diode and a resistor, these elements being arranged in series.
According to a first preferred embodiment of the elements constituting each devices mentioned above are arranged on one branch, the two branches being arranged in parallel.
the elements constituting the the negative half-cycle are arranged in a configuration which is the opposite to that of the ones constituting the detection device for the positive half-cycle.
According to another embodiment, the two detection devices are arranged in series on a single branch. In this case, the elements constituting the detection device for the mounted in a configuration negative half-cycle are which is the opposite to that of those constituting the detection device for the positive half-cycle.
Particularly advantageously, a resistor is arranged in parallel on each of the optocouplers, so as to make it possible to limit the influence of the leakage current of the Zener diodes.
Brief description of the figures.
The present invention will be described in more detail with the aid of the following figures:
Figures 1 and 2 represent outline diagrams which show the essential elements constituting a device according to .the present invention.
Figure 3 represents an embodiment of the device according to the present invention implemented by applying the principles described in figures 1 and 2.
IL 0 I 0 : L 6 Zd/dV
AP Ο Ο Ο 8 2 Ο
- 3 Description of some preferred embodiments of the invention .
In order to understand the principles underlying the design of the device according to the present· invention, reference will .be made essentially to Figures 1 and 2 which incorporate the principle characteristic elements.
The device according to the present invention, commonly referred to as an AC input cell for data acquisition circuits, as represented in Figure 1 is essentially composed of two branches, referred to as branches A and B, which respectively comprise a device for detecting a voltage higher than the reference for the positive half-cycle at the input voltage (branch A) and a device for detecting a voltage higher than the reference for the negative half-cycle of the input voltage (branch B) .
In general, the voltage thresholding is carried out by measuring the time for which, during one half20 cycle, the input voltage is greater than the reference voltage. If this time is greater than the predefined limit time, then the input voltage is considered as sufficient; otherwise, it is considered that there is not a sufficient voltage at the input.
j 25 The branches A and B comprise the same (T) elements, but arranged in an opposite configuration.
The branch A, which constitutes the detection device for the positive half-cycle, comprises a Zener diode DZ1, an optocoupler Ul, a diode D2 and a resistor Rl, these elements being arranged in series; whereas the branch B which constitutes the detection device for the
,. negative half-cycle comprises a Zener diode DZ2, an optocoupler U2, a diode D4 and a resistor R3, also arranged in series but in the opposite configuration.
_ According to a preferred embodiment, represented in Figure 2, it is conceivable for all the elements represented on the branches A and B in Figure to be arranged on a single branch, the two series of elements - Zener diode DZ1, optocoupler Ul and Zener
AP/P/ 9 7 / 0 1 0 71
AP 0. 0 0 8 2 0
DZ2, optocoupler configurations .
The main
U2
- 4 being arranged in opposite drawback of this configuration described in Figure 2 resides in the fact that the 5 Zener diodes DZ1 and DZ2 may have a particularly large leakage current which increases with temperature.
Advantageously, in order to solve this problem, a resistor R7 or R13 is arranged in parallel on the LEDs of the optocouplers U1 and U2.
It is also conceivable for another element, having the same function, to be arranged in parallel with U1 or U2. However, a resistor seems .to be the element with the most reliable and simplest design.
This device has the essential advantage of obtaining current thresholding.
Another advantage of this arrangement is a saving in volume and an increase in safety.
Figure 3 describes a practical example of a device according to the present invention, using the principles described in Figure 2.
The device described in Figure 3 is a 110 volt hertz AC input cell, essentially comprising 3 functional units arranged in cascade.
The first unit (unit I) essentially makes it possible to limit overvoltages.
The second unit (unit .II) guarantees consumption of the input power.
The third unit (unit III) performs the voltage thresholding of the cell, as well as the DC isolation between the input and the output processing lines.
The unit I consists of a varistore VR1, a resistor R5, diodes and spark gaps with a view to protecting the cell from overvoltages, whereas the unit
II which ensures the minimal rated consumption (reactive power) consists of a ”4 terminal capacitor
C4 coupling the input terminals of the cell to the unit
III which itself provides the voltage thresholding.
The varistore VR1 clips the overvoltages occurring during differential discharges, while the
AP/P/ 9 7 / 0 1 0 7 1
APO Ο 0 8 2 0
- 5 resistor R5 limits the amplitude of the current peaks in the 4 terminal capacitor C4 during the discharges, as well as the dV/dt.
The 4 terminal capacitor C4 should be 5 designed so as to ensure minimal consumption for a given 50 hertz input voltage.
The device . for detecting a voltage higher than the reference for the positive half-cycle of the input voltage, this device being located on branch A, essentially consists of the elements described in Figures 1 and 2: the Zener diode DZ'l, the optocoupler Ul, the diode D2 and the resistor Rl, while -the device for detecting a voltage higher than the reference for the negative half-cycle of the input voltage, which device is located on branch B, essentially consists of the same elements as the ones described in Figures 1 and 2: the Zener diode DZ2, the optocoupler U2, the diode D4 and the resistor R3.
Furthermore, a fuse FI or F2 is present in each of the branches A or B.
The principle selection criterion for the two main optocouplers Ul and U2 is that of operating with the lowest possible LED current, in order to make it possible to dissipate the minimum amount of power in the series resistors Rl and R3. This also makes it possible to minimize the contribution of the characteristic of the emission LED in the value of the voltage threshold.
The conduction time of the optocouplers Ul and
U2 is measured by sampling, 32 times at regular intervals of 20 milliseconds (therefore corresponding to a frequency of. 50 hertz), the electrical level delivered to the output processing lines and by counting the number of samples for which there is a logic state 0.
The emission LED of Ul emits throughout the time when the input voltage is higher than the threshold voltage of t.he branch A. The emission of this
LED of the optocoupler Ul entails earthing of' the
AP/P/ 97/01071 ~-;-4
AP Ο 0 Ο 8 2 Ο
- 6 resistors R2, R9 and RIO arranged in pull up on . the optocoupler Ul, thus leading to Ql being turned off and to the reading of a 0 logic level on the input of the multiplexer scanned by the processing line A (Ql emitter).
The time when emission LED of U2 emits throughout the input voltage is higher than threshold voltage of the branch B. The emission of this LED of the optocoupler U2 entails earthing of the 10 resistors R4 , Rll and R12 arranged in pull up on the optocoupler U2, thus leading to the reading of a 0 logic level on the input of the multiplexer -scanned by the processing line B (collector of the output transistor of U2).
There are two safety criteria guaranteed for
110 volt AC input cells:
the detection threshold must not fall below a limit for a 50 hertz sinusoidal voltage; the power consumed under a 50 hertz sinusoidal 20 voltage for an input in the logic state 1 cannot fall below a second limit value.
It should be noted that, apart from the 4 terminal capacitor, the components used to produce an AC input cell have no other intrinsic guarantee of 25 safety. For this reason, safety needs to rely on the use of the redundancy and checking the coherence of the data provided to the processing lines.
In particular, processing line A scans the voltage on the emitter Ql, while line B is connected to 30 the collector of the output transistor of the At the end of each scanning cycle, A for. mutual verification purposes, their own value for the number of samples taken when Ul or U2 were conducting.
The useful signals at the output of the cell are naturally presented on the collectors of the output optocouplers with a high output impedance level for the electrical state and a low impedance level for the electrical state. One precaution then consists in optocoupler U2 . and B exchange, the the
AP/P/ 9 7 / 0 1 0 7 1
APOΟ 0 8 2 0
- Ί using, just for the processing line A, a buffer stage with transistor inverting the level of the output impedances· so that there is this time a low impedance level for the 1 electrical state and a high impedance level for the 0 electrical state.
This characteristic has the risk of producing an OR logic function (as regards the state of the inputs) for the two processing lines in the event of defects consisting in the occurrence of a short-circuit between the output signals of the various cells.
This buffer stage consists of the transistor Q1 and the resistor R6 which are placed in the .processing line A.
By thus creating an asymmetry between the two 15 lines, in the event of multiple parasitic conducting circuits occurring, possibly affecting the same cells for the two processing lines, the following behaviour is profited from: the equivalent of a wired OR function (at the electrical level) is produced on the cells of line A, while the equivalent of a wired AND (at the electrical- level) is produced on the cells of line B.
This leads to a divergence between processing lines being detected as soon as the two cells affected by the parasitic conducting circuits are in different : 25 states.
Claims (4)
1. AC input cell intended for data acquisition circuits, particularly in railway applications,
5 comprising at least two lines (A and B) of identical elements arranged the opposite way round on the two lines, each line comprising at least one Zener diode (DZ1 or DZ2), an optocoupler (Ul or U2) comprising an LED diode, a diode (D2 or D4) and a resistor (Rl or
10 R3), each of these elements being arranged in series.
2. Cell according to Claim 1,' characterized in that the two lines (A and B) are arranged in. parallel, the elements of the first line being mounted in a configuration which is the opposite to that of the
15 elements of the second line.
3. Cell according to Claim 1, characterized in that the two lines of elements (A and B) are placed in series, the elements of the first line being mounted in a configuration which is the opposite to that of the
20 elements of the second line.
4 . Cell according to any one of the preceding claims, characterized in that a resistor (R7 or R13) is arranged in parallel on the LED diode of each of the optocouplers (Ul or U2).
25 5. Cell according to any one of the preceding claims, characterized in that, on just one of the lines (A), it comprises a buffer stage with transistor (Ql and R6) inverting the level of the output impedances.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP95870039 | 1995-04-19 | ||
| PCT/BE1996/000040 WO1996033086A1 (en) | 1995-04-19 | 1996-04-12 | Ac input cell for data acquisition circuits |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| AP9701071A0 AP9701071A0 (en) | 1997-10-31 |
| AP820A true AP820A (en) | 2000-04-20 |
Family
ID=8222128
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| APAP/P/1997/001071A AP820A (en) | 1995-04-19 | 1996-04-12 | AC input cell for data acquisition circuits. |
Country Status (21)
| Country | Link |
|---|---|
| US (1) | US6229349B1 (en) |
| EP (1) | EP0822907B1 (en) |
| JP (1) | JPH11504587A (en) |
| KR (1) | KR100403087B1 (en) |
| CN (1) | CN1182393A (en) |
| AP (1) | AP820A (en) |
| AT (1) | ATE189430T1 (en) |
| AU (1) | AU713905B2 (en) |
| CA (1) | CA2218502A1 (en) |
| CZ (1) | CZ289720B6 (en) |
| DE (1) | DE69606527T2 (en) |
| DK (1) | DK0822907T3 (en) |
| EA (1) | EA000206B1 (en) |
| ES (1) | ES2143756T3 (en) |
| GR (1) | GR3033056T3 (en) |
| HU (1) | HUP9802642A3 (en) |
| OA (1) | OA10527A (en) |
| PL (1) | PL180737B1 (en) |
| PT (1) | PT822907E (en) |
| SK (1) | SK283834B6 (en) |
| WO (1) | WO1996033086A1 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2763184B1 (en) * | 1997-05-07 | 1999-07-23 | Csee Transport | VALIDATION DEVICE FOR DIGITAL MESSAGES, APPLICABLE IN PARTICULAR TO RAIL TRAFFIC REGULATION SYSTEMS |
| FR2798538B1 (en) | 1999-09-10 | 2001-12-14 | Soprano | INPUT LOGIC CIRCUIT WITHOUT THERMAL DISSIPATION AND VOLTAGE ADAPTABLE |
| DE10329655A1 (en) * | 2003-07-01 | 2005-02-03 | Infineon Technologies Ag | Electronic component |
| US7808892B1 (en) * | 2006-11-21 | 2010-10-05 | Meteorcomm, Llc | Redundant data distribution systems and methods |
| US8674681B2 (en) * | 2010-05-25 | 2014-03-18 | Rockwell Automation Technologies, Inc. | Voltage detection and measurement circuit |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4091292A (en) * | 1977-03-07 | 1978-05-23 | General Signal Corporation | Fail-safe monitor of d.c. voltage |
| FR2569916B1 (en) * | 1984-09-03 | 1986-09-26 | Charbonnages De France | POWER CIRCUIT AND TRIGGERING DEVICE COMPRISING SAME |
| GB2166918B (en) * | 1984-11-13 | 1988-09-14 | Westinghouse Brake & Signal | A circuit arrangement for providing in a fail-safe manner an alternating output signal to a load |
| AUPM744794A0 (en) * | 1994-08-15 | 1994-09-08 | Garrick, Gilbert Alain Lindsay | Smoke alarm system with standby battery and elv reactive primary power supply |
-
1996
- 1996-04-12 CZ CZ19973220A patent/CZ289720B6/en not_active IP Right Cessation
- 1996-04-12 DK DK96908937T patent/DK0822907T3/en active
- 1996-04-12 JP JP8531361A patent/JPH11504587A/en active Pending
- 1996-04-12 HU HU9802642A patent/HUP9802642A3/en unknown
- 1996-04-12 US US08/952,362 patent/US6229349B1/en not_active Expired - Fee Related
- 1996-04-12 AP APAP/P/1997/001071A patent/AP820A/en active
- 1996-04-12 SK SK1415-97A patent/SK283834B6/en not_active IP Right Cessation
- 1996-04-12 DE DE69606527T patent/DE69606527T2/en not_active Expired - Lifetime
- 1996-04-12 CN CN96193384A patent/CN1182393A/en active Pending
- 1996-04-12 PT PT96908937T patent/PT822907E/en unknown
- 1996-04-12 CA CA002218502A patent/CA2218502A1/en not_active Abandoned
- 1996-04-12 KR KR1019970707288A patent/KR100403087B1/en not_active IP Right Cessation
- 1996-04-12 WO PCT/BE1996/000040 patent/WO1996033086A1/en active IP Right Grant
- 1996-04-12 AT AT96908937T patent/ATE189430T1/en active
- 1996-04-12 AU AU52626/96A patent/AU713905B2/en not_active Expired
- 1996-04-12 PL PL96323041A patent/PL180737B1/en unknown
- 1996-04-12 ES ES96908937T patent/ES2143756T3/en not_active Expired - Lifetime
- 1996-04-12 EA EA199700237A patent/EA000206B1/en not_active IP Right Cessation
- 1996-04-12 EP EP96908937A patent/EP0822907B1/en not_active Expired - Lifetime
-
1997
- 1997-10-17 OA OA70110A patent/OA10527A/en unknown
-
2000
- 2000-03-24 GR GR20000400744T patent/GR3033056T3/en unknown
Non-Patent Citations (1)
| Title |
|---|
| NONE * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1182393A (en) | 1998-05-20 |
| JPH11504587A (en) | 1999-04-27 |
| OA10527A (en) | 2002-04-29 |
| ES2143756T3 (en) | 2000-05-16 |
| AP9701071A0 (en) | 1997-10-31 |
| EP0822907B1 (en) | 2000-02-02 |
| US6229349B1 (en) | 2001-05-08 |
| DE69606527D1 (en) | 2000-03-09 |
| ATE189430T1 (en) | 2000-02-15 |
| CA2218502A1 (en) | 1996-10-24 |
| DE69606527T2 (en) | 2000-08-17 |
| AU713905B2 (en) | 1999-12-16 |
| PL323041A1 (en) | 1998-03-02 |
| PL180737B1 (en) | 2001-03-30 |
| EA199700237A1 (en) | 1998-02-26 |
| HUP9802642A3 (en) | 1999-08-30 |
| GR3033056T3 (en) | 2000-08-31 |
| SK141597A3 (en) | 1998-06-03 |
| KR19980703887A (en) | 1998-12-05 |
| HUP9802642A2 (en) | 1999-03-29 |
| PT822907E (en) | 2000-07-31 |
| EP0822907A1 (en) | 1998-02-11 |
| WO1996033086A1 (en) | 1996-10-24 |
| KR100403087B1 (en) | 2004-02-11 |
| CZ322097A3 (en) | 1998-01-14 |
| SK283834B6 (en) | 2004-03-02 |
| EA000206B1 (en) | 1998-12-24 |
| AU5262696A (en) | 1996-11-07 |
| DK0822907T3 (en) | 2000-07-24 |
| CZ289720B6 (en) | 2002-03-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106199477A (en) | Noise generation circuit, self-checking circuit, AFCI and photovoltaic generating system | |
| AP820A (en) | AC input cell for data acquisition circuits. | |
| US4210906A (en) | Transient suppression and detection system with operational indicator means | |
| CN204950087U (en) | Intelligent express cabinet | |
| CA1154500A (en) | Vital contact isolation circuit | |
| KR860000736A (en) | Adapter for surge protection against high brightness and incandescent lamps | |
| CN214013869U (en) | Reliable single-phase wiring detection circuit of commercial power | |
| US5096147A (en) | In-circuit contact monitor | |
| KR19980703888A (en) | DC input cell for data acquisition circuit | |
| CN2433758Y (en) | Overcurrent protecter | |
| Kumar et al. | Surge immunity protection in AC LED Street Lights | |
| CN116526475B (en) | High-reliability power supply box transformer substation | |
| CN108646164A (en) | High-pressure thyristor on-Line Monitor Device | |
| CN204614735U (en) | A kind of relay | |
| RU2103778C1 (en) | Monitoring device for power capacitor bank | |
| CN2144360Y (en) | Protector for power cut and thunderbolt | |
| CN114784752B (en) | Leakage protection device and detection method thereof | |
| CN216904266U (en) | Multifunctional household power consumption protection device | |
| CN212459884U (en) | Acquisition circuit compatible with monostable bistable state and passive control output | |
| CN205945011U (en) | Colliery is flame -proof type long distance short -circuiting device in pit | |
| CN2377757Y (en) | Three-phase civil power supply safety protection monitor | |
| CN116155259A (en) | Thick film circuit for prolonging service life of optocoupler | |
| CN2038672U (en) | Plug (socket) with current leakage alarming function | |
| RU2081421C1 (en) | Electric network tension indication device | |
| CN2138851Y (en) | Multifunctional protector |