CN2924549Y

CN2924549Y - Lighting cable power-off stealing detection device

Info

Publication number: CN2924549Y
Application number: CN 200620104705
Authority: CN
Inventors: 周逊盛; 董建平; 李志波; 周永
Original assignee: RUIQI INFORMATION TECHNOLOGY Co Ltd HANGZHOU
Current assignee: RUIQI INFORMATION TECHNOLOGY Co Ltd HANGZHOU
Priority date: 2006-06-15
Filing date: 2006-06-15
Publication date: 2007-07-18
Anticipated expiration: 2016-06-15

Abstract

The utility model relates to a cable theft detection device at the situations of lighting cables power outages. The existing detection method is unreliable. The utility model comprises a mainframe arranged in cable switch box and a terminal arranged at the end of the cable. The mainframe comprises a power supply, electronic switches, a sampling resistor, AD converters and microprocessors. The terminal comprises power modules, load, electronic switches and microprocessors. The terminal of the utility model is a dynamic DC impedance, if the mainframe can detect the DC impedance which changes according to the default laws, the cable is normal, thus the influences of fixed impedance can be greatly eliminated.

Description

Stolen pick-up unit during the light conduits outage

Technical field

The utility model relates to a kind of pick-up unit, the stolen pick-up unit of cable under especially a kind of light conduits powering-off state.

Background technology

Light conduits is installed in open-air stolen easily, in order can in time to find when stolen, just needs a kind of checkout equipment of cable break.Whether only relate to cable detection streamer under cold situation here breaks.Traditional method has two kinds, a kind of is the means of communication of power carrier, be exactly " main frame " equipment of in the powered switch case, installing, " end " equipment is installed at each end at cable, pass through power carrier communication between them, in case cable is stolen, then Communications failure can be judged as broken string.This method has two problems to be difficult to overcome, and one is generally all to be gas-discharge lamp on the light conduits, and each lamp all is with a building-out capacitor, can seriously absorb power carrier signal, so false alarm is very serious; The another one problem is that the communication apparatus of power carrier generally all will be obtained power supply from line of electric force, generally occur under the situation of not having electricity daytime and steal, in order to make communication to proceed, just must use storage battery power supply, and the charging and discharging of accumulator circulation has certain number of times, need periodic maintenance, this has just increased product the workload that safeguard the back has been installed.Another is a method of measuring the impedance of cable, is exactly one " main frame " is installed in switch box, at each end of cable a small-sized transformer is installed.Under the state of cable energising, terminal transformer is to almost not influence of circuit; Under the cold situation of cable, " main frame " can measure the dc impedance of cable, and this impedance is exactly the dc impedance of transformer.In case this impedance is worth greater than certain, think that then cable disconnects.The shortcoming of this method is: the state more complicated of cable, because cable is embedded in undergroundly, leak electricity between the cable that ground vapour can cause, and consumer makes moist and also has electric leakage, thereby causes main frame to detect failure.

Summary of the invention

The purpose of this utility model overcomes the deficiencies in the prior art exactly, and the technical scheme of the cable stolen pick-up unit of a kind of light conduits under powering-off state is provided.

The utility model comprises the end that is arranged on the main frame in the cable switch case and is installed in the cable end.Comprise power supply, electronic switch, sample resistance, AD converter and microprocessor in the main frame.Power supply is powered to other parts, and electronic switch connects power supply and cable, and the input of AD converter accesses sample resistance, AD converter digital interface receive microprocessor.Comprise power module, load, electronic switch and microprocessor in the end.Power module is powered to other parts, and the output terminal of microprocessor is connected to the input end of electronic switch, and the electronic switch output terminal is connected to load.When electronic switch closes, load is parallel to cable, otherwise load disconnects from cable.

Microprocessor in the main frame adopts 8 general single-chip microcomputers, the AT89C51 of atmel corp for example, and it can gather the AD data, and calculates electric current, analyzes whether comprise terminal signal in this electric current then.Microprocessor in the end adopts 8 general single-chip microcomputers, the LPC932 of PHILIPS company for example, and it can send pulse control electronic switch.

The utility model makes terminal transformer into a dynamic dc impedance, if main frame can detect the dc impedance that changes according to default rule, thinks that then cable is normal, so just can get rid of the influence of blocked impedance greatly, and it is more accurate to detect.

The utility model is compared with original technology, has the following advantages:

1, overcomes the building-out capacitor influence of thousands of microfarads on the road lighting cable;

2, overcome the cable leakage influence;

3, the take over party can be sent waveform clearly through after the digital signal processing, can calculate signal to noise ratio (S/N ratio), signal amplitude etc., therefore can judge the communication degree of reliability for complicated circuit, the diagnosis communication circuit;

4, communication distance and cable length are irrelevant, but the electric leakage of the direct current of cable is relevant, therefore are specially adapted to illuminating line.

Description of drawings

Fig. 1 is the one-piece construction synoptic diagram;

Fig. 2 is the structured flowchart in the main frame;

Fig. 3 is a structural representation in the end.

Embodiment

As Fig. 1, Fig. 2 and shown in Figure 3, this pick-up unit comprises main frame 1 that is arranged in the cable switch case and the end 4 that is installed in the cable end.Comprise power supply 5, electronic switch 4, sample resistance 6, AD converter 7, microprocessor 8 in the main frame 1.Power supply 5 is to the other parts power supply, and electronic switch 8 connects power supply 5 and cable 2, and the input of AD converter 7 accesses sample resistance, and the digital interface of AD converter 7 is received microprocessor 8.Comprise power module 12, load 9, electronic switch 10, microprocessor 11 in terminal 3.Power module 12 is to the other parts power supply, and the output terminal of microprocessor 11 is connected to the input end of electronic switch 10, and electronic switch 10 output terminals are connected to load 9.When electronic switch 10 closures, load 9 is parallel to cable 2, otherwise load 9 disconnects from cable 2.

When the switch in the switch box disconnects, the cable no power, after this " main frame " adds a low-voltage direct on cable, for example the low-voltage direct of 10V (this moment circuit load or disconnect voluntarily by contactor, perhaps do not work, also do not absorb any electric current because supply voltage is too low), then " end " utilizes this voltage to start working, periodically a load of inside is connected or disconnect, make the variation of the electric current generating period that flows through cable.Main frame then detects the electric current that is added on the cable, and judges according to the variation of electric current whether end exists.

If cable is cut off midway, then end is no longer worked, and whether the detected electric current of main frame will be invariable (rather than cycle change electric current), cut off thereby can judge cable in view of the above.

The implementation method of main frame: main frame is installed in the switch box, always have in the switch box under the normal condition electricity, can power to main frame.

Electronic switch in the main frame disconnects when cable is switched on, in case have a power failure then close automatically, to cable power supply." current measurement " module can be measured the electric current of supply cable, and the result is sent to " microprocessor ", and it can judge whether the variation of electric current meets predetermined rule, if meet, thinks that then cable is not disconnected.Thereby reach the purpose of detection streamer broken string.

Terminal implementation method: no-output when power module is interchange at voltage cable, this power devices is given in galvanic current source of output when voltage cable is low-voltage direct, microprocessor controls " electronic switch " is periodically closed, disconnection, thereby makes the variation of the electric current generating period that " main frame " provides.

Claims

Stolen pick-up unit when 1, light conduits cuts off the power supply, comprise the end (3) that is arranged on the main frame (1) in the cable switch case and is installed in the cable end, it is characterized in that comprising in the main frame (1) power supply (5), electronic switch (4), sample resistance (6), AD converter (7) and microprocessor (8); Power supply (5) is to the other parts power supply, and electronic switch (4) connects power supply (5) and cable (2), and the input of AD converter (7) accesses sample resistance (6), and the digital interface of AD converter (7) is received microprocessor (8); Comprise power module (12), load (9), electronic switch (10) and microprocessor (11) in terminal (3); Power module (12) is to the other parts power supply, and the output terminal of microprocessor (11) is connected to the input end of electronic switch (10), and electronic switch (10) output terminal is connected to load (9); When electronic switch (10) was closed, load (9) was parallel to cable (2), otherwise load (9) disconnects from cable (2).