CA1171462A - Device for automatically monitoring an independent current supply - Google Patents
Device for automatically monitoring an independent current supplyInfo
- Publication number
- CA1171462A CA1171462A CA000342423A CA342423A CA1171462A CA 1171462 A CA1171462 A CA 1171462A CA 000342423 A CA000342423 A CA 000342423A CA 342423 A CA342423 A CA 342423A CA 1171462 A CA1171462 A CA 1171462A
- Authority
- CA
- Canada
- Prior art keywords
- monitoring
- humidity
- transponder
- voltage
- sensor
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
- G01R19/16533—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values characterised by the application
- G01R19/16538—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values characterised by the application in AC or DC supplies
- G01R19/16542—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values characterised by the application in AC or DC supplies for batteries
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
- G01R31/3644—Constructional arrangements
- G01R31/3648—Constructional arrangements comprising digital calculation means, e.g. for performing an algorithm
-
- G—PHYSICS
- G08—SIGNALLING
- G08G—TRAFFIC CONTROL SYSTEMS
- G08G1/00—Traffic control systems for road vehicles
- G08G1/123—Traffic control systems for road vehicles indicating the position of vehicles, e.g. scheduled vehicles; Managing passenger vehicles circulating according to a fixed timetable, e.g. buses, trains, trams
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
- G01R31/3644—Constructional arrangements
- G01R31/3646—Constructional arrangements for indicating electrical conditions or variables, e.g. visual or audible indicators
Landscapes
- General Physics & Mathematics (AREA)
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Power Engineering (AREA)
- Alarm Systems (AREA)
- Arrangements For Transmission Of Measured Signals (AREA)
- Mobile Radio Communication Systems (AREA)
- Traffic Control Systems (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
- Testing Or Calibration Of Command Recording Devices (AREA)
- Electric Propulsion And Braking For Vehicles (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
Abstract of the Invention This invention relates to a device for automatically monitoring the charging state of the independent current supply of the transponder of a network for determining the position of traffic systems, wherein there is coordinated with the current supply (primary batteries or accumulators ad-apted to be charged via solar cells) a monitoring sensor with a defined re-sponse threshold. The humidity of the ambient atmosphere is additionally monitored by providing a sensor inside the device. The sensor indicates any excess of a predetermined limiting value of the humidity inside the trans-ponder which under normal operational conditions is kept at low values. If the humidity sensor detects excess humidity, it produces a signal which is mixed with the monitoring signal via an OR gate and included in a response telegram to be sent to an interrogating unit.
Description
~7~ Z
The invention relates to a device for the automatic monit-oring of the state of an independ~ t electric current suFply source. In position-determining radio networks for use in traf-fic systems positional data may be sent by a transponder in radio rontact with an interrogation unit that is installed in a vehicle. The interrogation unit can be supplied from the veh-icle power supply, but the power supply for each transponder may present serious problems, and independ~nt sources, such as prim-ary batteries or long-life accumulators, possibly charged via solar cells, may be preferred. In this case it is desirable to provide a monitoring sensor having a response threshold which exceeds the minimum voltage required for satisfactory operation by a value which can be adjusted in a determinate manner, which sensor produces an alarm signal if the result of the voltage measurement carried out during an interrogation, this signal being fed as a monitoring signal, to a telegram register to be incorporated in the transponder response.
The `functioning reliability in a punctiform system of this kind in which data is transmitted from a transponder to a read-out device by modulated micro-wave signals, is dependent not only upon the charge state of the indepen ~nt current supply - source, but also upon the reliable functioning of the circuitry in these micro-wave devicesO For example, in the event of dam-age to the housing, this reliable functioning can be severely influenced in an adverse manner by moisture, which can lead to sudden breakdowns, or slow deterioration, e.g. where metallic circuit components do not change their effective electrical - - 2 ~
, t , ~ r , ~71~Z
., .
characteristics significantly until serious corrosion occurs.
Consequently, although the operating reliability of the system may be impaired in a short or a long term, the harmful influence of any moisture is not normally distinguishable until the trans-ponder device actually breaks down.
One object of the present invention is to provide an imp-roved form of the monitoring device described in the introduct-ion, in which at the atmospheric humidity within the transponder device is also monitored.
The invention consists in a device for the automatic mon-~ itoring of.the state of an independ~nt electric current supply : . source, for a transponder of a position determining network in a i.
traffic.system, which transponder is in radio contact with a mobile interrogation unit, a voltage charge state monitoring . , ;, 15 sensor having a response threshold which exceeds the minimum ... . ~ ~ - . . .
.- voltage required for satisfactory.operatiPn by a value whi-ch may be set in a determinate manner being provided to produce an . . .
~ alarm slgnal if the result of the voltage measurement during.any : interrogation indicates a voltage below said threshold,~and fed ~ 20 via an OR-gate to be included in a telegram- register, and an:~ .
; atmospheric humidity monitoring sensor being provided to check : that the interior of the transponder is maintained at a low at-mospheric humidity in its normal operating state, there being arranged close to the micro wave circuitry which is to be mon-25 itored a humidity probe which responds to indicate the over-stepping.of a.given limit value of the atmospheric humidity, and thereupon produce an alarm signal fed Vla said OR-gate to be _ 3 _ 4~;~
included in said telegram register.
The invention will now be described with reference to the drawings, in which:
Figure 1 schematically illustrates one exemplary embodiment construct-ed in accordance with the invention; and Figure 2 plots the content of a transponder response signal against a time scale.
Figure 1 only illustrates the monitoring circuit of a transponder.
A power source having terminals +UB and OV can be connected via a switch Su 10 to a first monitoring stage, comprising a transistor TSl of the npn type, a collector resistor Rl in its collector circuit, and a voltage divider which consists of resistors R2 and R3 in series with a Zener diode Z with the junction of the resistors R2 and R3 being connected to the base of the tran-sistor TSl. From the collector of the transistor TSl a line Ll leads to one input of an OR-gate ~, whose output is connected to an input of a telegram register TR. Via this line Ll a source voltage monitoring signal is fed to the telegram register TR during any interrogation, if necessary. This monitoring circuit, which serves to monitor the battery voltage, is designed to be such that when the voltage falls below a specific voltage, (alarm voltage), the transistor TSl blocks.
In order that the atmospheric moisture may be monitored, the circuit is supplemented in the following manner. Parallel to the emitter-collector path of the first transistor TSl there is connected a second transistor TS2 of the pnp type with a collector load R4 and a voltage divider consisting of resistors .g~ ' .
:
.
, 6~:
R5 R~, and a humidity-dependent resistor R7 connected in series, the junction oE the resistors R5 and R6 being connected to the base of -the transistor TS2, whose collector ls connected to the second input of the OR-gate G. The path of the battery voltage is via the change-over switch Su, when the latter is actuated by a monitoring pulse I~ to connect the monitoring circuits briefly (C~1%o) during the response signal telegram. The illustrated position of the change-over switch applies to the situation in which both monitoring circuits, i.e. the monitoring circuits for the battery charge state and the monitoring circuit for the at-mospheric humidity, are inactive. In this position the monitor-ing circuits comprising the transistors TSl and TS2 receive no operating voltage and the two gate inputs are each supplied, via the line Ll and resistor Rl, and via the line L2 and resistor R4, with a logic "0" (OV). By means of the the monitoring pulse I~
the switch Su connects the operating voltage for a short length of time to the monitoring circuits. When the voltage UB has fallen below a given threshold value, so that, during the course of the monitoring pulse I~ the Zener diode Z stops being con-ductive, then a logic "1" (+UB) is applied to the gate input viathe line Ll and the resistor Rl. If the voltage value of +UB
still exceeds the given threshold value, during the course of the monitoring pulse I~ the Zener diode Z becomes conductive, and consequently the transistor TSl conducts. The line Ll is then connected via the transistor TSl to O V, and no alarm is produced during the monitoring pulse I~.
The resistance value of the humidity-dependent resistor ~71~
R7 is very closely dependent upon the a-tmospheric humidity, if possible with logarithmic precision, and in such manner that the resistance value reduces with increasing atmospheric humidity.
A reduc-tion in the resistance oE the resistor R7 causes -the transistor TS2 to become conductive and emit a signal in the form of a logic "1" via the line L2 to the OR-gate G. In order to economise on operating current, the transistor TS2 and the transistor TSl are only connected to the operating voltage +U~
via the switch Su within the duration of a monitoring pulse I~.
On delivery, or Eollowing servicing work, the air contained in the interior of the micro-wave device will have the lowest pos-sible humidity.
The above described monitoring of the atmospheric humidity is naturally not limited to use in an answer-back device of a locating system but can be used correspondingly in any other housings, and may be used by itself, and not merely in combin-ation with a battery voltage monitoring unit, as has been described above.
In the telegram register TR the monitoring signal is inserted into the telegram produced by the transponder as a response signal. Figure 2 is a schematic graphical illustration of a diagram composed of several linked blocks, namely the syn-chronisation signals SynZ, the answer-back device data AGD, the monitoring signal UZ, and a parity check signal KZ. In response to any enquiry from an interrogation unit, the latter is supplied with a telegram of this kind from the transponder. As this signal will be received by the central control station, this is kept constantly informed of possible disturbances in any transponder.
.
.
i........................................... .
~, - . .
,.. ~ , , .. - - . . . , :. -. ~
: ~ . . ~ . .
- . . .
, . ~ .
, ~ .... ..
. .. . .
.- .:
- . .
.~ - .. . -.. . .
- . .
- 7 - .
.
The invention relates to a device for the automatic monit-oring of the state of an independ~ t electric current suFply source. In position-determining radio networks for use in traf-fic systems positional data may be sent by a transponder in radio rontact with an interrogation unit that is installed in a vehicle. The interrogation unit can be supplied from the veh-icle power supply, but the power supply for each transponder may present serious problems, and independ~nt sources, such as prim-ary batteries or long-life accumulators, possibly charged via solar cells, may be preferred. In this case it is desirable to provide a monitoring sensor having a response threshold which exceeds the minimum voltage required for satisfactory operation by a value which can be adjusted in a determinate manner, which sensor produces an alarm signal if the result of the voltage measurement carried out during an interrogation, this signal being fed as a monitoring signal, to a telegram register to be incorporated in the transponder response.
The `functioning reliability in a punctiform system of this kind in which data is transmitted from a transponder to a read-out device by modulated micro-wave signals, is dependent not only upon the charge state of the indepen ~nt current supply - source, but also upon the reliable functioning of the circuitry in these micro-wave devicesO For example, in the event of dam-age to the housing, this reliable functioning can be severely influenced in an adverse manner by moisture, which can lead to sudden breakdowns, or slow deterioration, e.g. where metallic circuit components do not change their effective electrical - - 2 ~
, t , ~ r , ~71~Z
., .
characteristics significantly until serious corrosion occurs.
Consequently, although the operating reliability of the system may be impaired in a short or a long term, the harmful influence of any moisture is not normally distinguishable until the trans-ponder device actually breaks down.
One object of the present invention is to provide an imp-roved form of the monitoring device described in the introduct-ion, in which at the atmospheric humidity within the transponder device is also monitored.
The invention consists in a device for the automatic mon-~ itoring of.the state of an independ~nt electric current supply : . source, for a transponder of a position determining network in a i.
traffic.system, which transponder is in radio contact with a mobile interrogation unit, a voltage charge state monitoring . , ;, 15 sensor having a response threshold which exceeds the minimum ... . ~ ~ - . . .
.- voltage required for satisfactory.operatiPn by a value whi-ch may be set in a determinate manner being provided to produce an . . .
~ alarm slgnal if the result of the voltage measurement during.any : interrogation indicates a voltage below said threshold,~and fed ~ 20 via an OR-gate to be included in a telegram- register, and an:~ .
; atmospheric humidity monitoring sensor being provided to check : that the interior of the transponder is maintained at a low at-mospheric humidity in its normal operating state, there being arranged close to the micro wave circuitry which is to be mon-25 itored a humidity probe which responds to indicate the over-stepping.of a.given limit value of the atmospheric humidity, and thereupon produce an alarm signal fed Vla said OR-gate to be _ 3 _ 4~;~
included in said telegram register.
The invention will now be described with reference to the drawings, in which:
Figure 1 schematically illustrates one exemplary embodiment construct-ed in accordance with the invention; and Figure 2 plots the content of a transponder response signal against a time scale.
Figure 1 only illustrates the monitoring circuit of a transponder.
A power source having terminals +UB and OV can be connected via a switch Su 10 to a first monitoring stage, comprising a transistor TSl of the npn type, a collector resistor Rl in its collector circuit, and a voltage divider which consists of resistors R2 and R3 in series with a Zener diode Z with the junction of the resistors R2 and R3 being connected to the base of the tran-sistor TSl. From the collector of the transistor TSl a line Ll leads to one input of an OR-gate ~, whose output is connected to an input of a telegram register TR. Via this line Ll a source voltage monitoring signal is fed to the telegram register TR during any interrogation, if necessary. This monitoring circuit, which serves to monitor the battery voltage, is designed to be such that when the voltage falls below a specific voltage, (alarm voltage), the transistor TSl blocks.
In order that the atmospheric moisture may be monitored, the circuit is supplemented in the following manner. Parallel to the emitter-collector path of the first transistor TSl there is connected a second transistor TS2 of the pnp type with a collector load R4 and a voltage divider consisting of resistors .g~ ' .
:
.
, 6~:
R5 R~, and a humidity-dependent resistor R7 connected in series, the junction oE the resistors R5 and R6 being connected to the base of -the transistor TS2, whose collector ls connected to the second input of the OR-gate G. The path of the battery voltage is via the change-over switch Su, when the latter is actuated by a monitoring pulse I~ to connect the monitoring circuits briefly (C~1%o) during the response signal telegram. The illustrated position of the change-over switch applies to the situation in which both monitoring circuits, i.e. the monitoring circuits for the battery charge state and the monitoring circuit for the at-mospheric humidity, are inactive. In this position the monitor-ing circuits comprising the transistors TSl and TS2 receive no operating voltage and the two gate inputs are each supplied, via the line Ll and resistor Rl, and via the line L2 and resistor R4, with a logic "0" (OV). By means of the the monitoring pulse I~
the switch Su connects the operating voltage for a short length of time to the monitoring circuits. When the voltage UB has fallen below a given threshold value, so that, during the course of the monitoring pulse I~ the Zener diode Z stops being con-ductive, then a logic "1" (+UB) is applied to the gate input viathe line Ll and the resistor Rl. If the voltage value of +UB
still exceeds the given threshold value, during the course of the monitoring pulse I~ the Zener diode Z becomes conductive, and consequently the transistor TSl conducts. The line Ll is then connected via the transistor TSl to O V, and no alarm is produced during the monitoring pulse I~.
The resistance value of the humidity-dependent resistor ~71~
R7 is very closely dependent upon the a-tmospheric humidity, if possible with logarithmic precision, and in such manner that the resistance value reduces with increasing atmospheric humidity.
A reduc-tion in the resistance oE the resistor R7 causes -the transistor TS2 to become conductive and emit a signal in the form of a logic "1" via the line L2 to the OR-gate G. In order to economise on operating current, the transistor TS2 and the transistor TSl are only connected to the operating voltage +U~
via the switch Su within the duration of a monitoring pulse I~.
On delivery, or Eollowing servicing work, the air contained in the interior of the micro-wave device will have the lowest pos-sible humidity.
The above described monitoring of the atmospheric humidity is naturally not limited to use in an answer-back device of a locating system but can be used correspondingly in any other housings, and may be used by itself, and not merely in combin-ation with a battery voltage monitoring unit, as has been described above.
In the telegram register TR the monitoring signal is inserted into the telegram produced by the transponder as a response signal. Figure 2 is a schematic graphical illustration of a diagram composed of several linked blocks, namely the syn-chronisation signals SynZ, the answer-back device data AGD, the monitoring signal UZ, and a parity check signal KZ. In response to any enquiry from an interrogation unit, the latter is supplied with a telegram of this kind from the transponder. As this signal will be received by the central control station, this is kept constantly informed of possible disturbances in any transponder.
.
.
i........................................... .
~, - . .
,.. ~ , , .. - - . . . , :. -. ~
: ~ . . ~ . .
- . . .
, . ~ .
, ~ .... ..
. .. . .
.- .:
- . .
.~ - .. . -.. . .
- . .
- 7 - .
.
Claims (5)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A device for the automatic monitoring of the state of an independent electric current supply source, for a transponder of a position determining network in a traffic system, which transponder is in radio contact with a mobile interrogation unit, a voltage charge state monitoring sensor having a response threshold which exceeds the minimum voltage required for satisfactory operation by a value which may be set in a determinate manner being provided to produce an alarm signal if the result of the voltage measurement during any interrogation indicates a voltage below said threshold, and fed via an OR-gate to be included in a telegram register, and an atmospheric humidity mon-itoring sensor being provided to check that the interior of the transponder is maintained at a low atmospheric humidity in its normal operating state, there being arranged close to the microwave circuitry which is to be monitored a humidity probe which responds to indicate the overstepping of a given limit value of the atmospheric humidity, and thereupon produce an alarm signal fed via said OR-gate to be included in said telegram register.
2. A device as claimed in Claim 1, in which said humidity probe consists of a resistor whose resistance value is closely dependent upon the atmospheric humidity.
3. A device as claimed in Claim 2, in which any change in resistance is converted via a transistor circuit into one of the two binary values and fed to said OR-gate.
4. A device as claimed in any one of Claims 1 to 3, in which means are provided by which the monitoring circuits are connected for only a short length of time during any interrogation.
5. A device as claimed in any one of Claims 1 to 3, in which a change over switch that is actuated by a monitoring pulse is arranged in the supply line from the battery voltage supply source.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2855809A DE2855809C2 (en) | 1978-12-22 | 1978-12-22 | Device for automatic monitoring of the state of charge of a network-independent power supply and the humidity in the response device of a system for determining the location of traffic facilities |
| DEP2855809.0 | 1978-12-22 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1171462A true CA1171462A (en) | 1984-07-24 |
Family
ID=6058176
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000342423A Expired CA1171462A (en) | 1978-12-22 | 1979-12-20 | Device for automatically monitoring an independent current supply |
Country Status (10)
| Country | Link |
|---|---|
| EP (1) | EP0013706B1 (en) |
| JP (1) | JPS5927534B2 (en) |
| AT (1) | AT371953B (en) |
| AU (1) | AU533556B2 (en) |
| CA (1) | CA1171462A (en) |
| DE (2) | DE2855809C2 (en) |
| DK (1) | DK150867C (en) |
| ES (1) | ES487212A0 (en) |
| FI (1) | FI68919C (en) |
| NO (1) | NO147165C (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2529002A2 (en) * | 1979-10-10 | 1983-12-23 | Laporte Yves | Autonomous multi-facet road sign with remote control - uses photo-voltaic cell array to provide energy for rechargeable battery driving motor which can act directly or pressurise fluid |
| ZA825021B (en) * | 1981-07-14 | 1983-06-29 | Tag Radionics Ltd | Coded information arrengements |
| JP7172838B2 (en) * | 2019-04-26 | 2022-11-16 | 株式会社デンソー | battery monitor |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3401373A (en) * | 1965-10-24 | 1968-09-10 | Ray D. Risner | Vehicle warning and alarm system |
| DE2022447A1 (en) * | 1970-05-08 | 1971-11-18 | Keller Hans Dipl Ing | Battery control procedures for photographic cameras |
| US3979667A (en) * | 1974-01-02 | 1976-09-07 | Diplex Limited | Electrical indicators |
| JPS5144979U (en) * | 1974-10-01 | 1976-04-02 | ||
| DE2816781C2 (en) * | 1978-04-18 | 1979-12-20 | Siemens Ag, 1000 Berlin Und 8000 Muenchen | Device for automatic monitoring of the charge status of mains-independent power supplies |
-
1978
- 1978-12-22 DE DE2855809A patent/DE2855809C2/en not_active Expired
-
1979
- 1979-11-20 DE DE7979104615T patent/DE2966565D1/en not_active Expired
- 1979-11-20 EP EP79104615A patent/EP0013706B1/en not_active Expired
- 1979-12-14 NO NO794100A patent/NO147165C/en unknown
- 1979-12-17 AT AT0793179A patent/AT371953B/en not_active IP Right Cessation
- 1979-12-20 AU AU54113/79A patent/AU533556B2/en not_active Ceased
- 1979-12-20 CA CA000342423A patent/CA1171462A/en not_active Expired
- 1979-12-21 ES ES487212A patent/ES487212A0/en active Granted
- 1979-12-21 FI FI794046A patent/FI68919C/en not_active IP Right Cessation
- 1979-12-21 JP JP54165800A patent/JPS5927534B2/en not_active Expired
- 1979-12-21 DK DK551979A patent/DK150867C/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| AU5411379A (en) | 1980-06-26 |
| AT371953B (en) | 1983-08-25 |
| NO794100L (en) | 1980-06-24 |
| DE2966565D1 (en) | 1984-02-23 |
| NO147165B (en) | 1982-11-01 |
| ES8100513A2 (en) | 1980-11-01 |
| DE2855809B1 (en) | 1979-10-11 |
| AU533556B2 (en) | 1983-12-01 |
| FI794046A (en) | 1980-06-23 |
| ATA793179A (en) | 1982-12-15 |
| FI68919C (en) | 1985-11-11 |
| ES487212A0 (en) | 1980-11-01 |
| JPS5590144A (en) | 1980-07-08 |
| EP0013706A1 (en) | 1980-08-06 |
| NO147165C (en) | 1983-02-09 |
| DK150867C (en) | 1988-06-06 |
| EP0013706B1 (en) | 1984-01-18 |
| DK150867B (en) | 1987-07-06 |
| DE2855809C2 (en) | 1980-06-19 |
| DK551979A (en) | 1980-06-23 |
| FI68919B (en) | 1985-07-31 |
| JPS5927534B2 (en) | 1984-07-06 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |