CN201716385U

CN201716385U - Monostable circuit of alarm for automatic detection of communication cable breakpoint

Info

Publication number: CN201716385U
Application number: CN201020199451XU
Authority: CN
Inventors: 王立华; 王明合
Original assignee: Shandong University of Science and Technology
Current assignee: Shandong University of Science and Technology
Priority date: 2010-05-24
Filing date: 2010-05-24
Publication date: 2011-01-19
Anticipated expiration: 2020-05-24

Abstract

The utility model relates to a monostable circuit of an alarm for automatic detection of communication cable breakpoints. The alarm comprises a control circuit and a monostable circuit connected electrically, the monostable circuit comprises an integrated circuit IC1, a capacitor C1, a capacitor C2, a resistor R1 and a resistor R2, the grounding end of the integrated circuit IC1 is connected with a control voltage end through the capacitor C2, the triggering end of the integrated circuit IC1 is connected with one end of the capacitor C1 and one end of the resistor R1, the other end of the capacitor C1 is connected with a triggering signal, the other end of the resistor R1 is connected with a power supply, the reset end is connected with the power supply, the threshold end is connected with a discharge end and one end of the resistor R2, a cable is grounded, and the other end of the resistor R2 is connected with the power supply. The utility model can realize the real-time detection of breakpoints of the cable and judge the distances of the breakpoints through the monostable circuit and the control circuit and can monitor the external spare cable only through simple setting. When the cable is cut off or fails, the utility model can rapidly measure the distance of the breakpoint of the cable, and the user can dial the telephone number stored in advance for voice alarm.

Description

Monostable circuit of automatic detection warning instrument for communication cable breakpoint

Technical field

The utility model relates to a kind of detection alarm instrument, specifically, relates to a kind of detection alarm instrument monostable circuit that can detect automatically communication cable breakpoint, belongs to electronic technology field.

Background technology

High speed development along with modern communications, the various types of communication circuit is more and more, and the complexity of arranging net, and along with the development in city, the excavation of urban road also increases day by day, makes communication line not only be subjected to elemental influence and causes communication cable the situation of breakpoint to occur, also is subjected to some artificial factor, cause communication cable the situation of breakpoint to occur as road excavation and cable are stolen etc., influence the operation of whole communication network.How in time to grasp the break-make situation of various communication cables reliably, at present, also rest on and have only when breakpoint fault appears in communication cable, just go the on-the-spot break-make that detects communication line by specific purpose tool, this detection means efficiency ratio is lower, and the waste lot of manpower and material resources has brought very big difficulty for the on-call maintenance of communication cable, can not adapt to the development of telecommunications, influence the service quality of the whole communications industry.

The utility model content

Problem to be solved in the utility model is at above deficiency, and a kind of Monostable circuit of automatic detection warning instrument for communication cable breakpoint of detection streamer breakpoint automatically is provided.

For overcoming the above problems, the technical scheme that the utility model adopted is: Monostable circuit of automatic detection warning instrument for communication cable breakpoint, it is characterized in that: described alarm comprises the control circuit of electrical connection, monostable circuit, monostable circuit comprises integrated circuit (IC) 1, capacitor C 1, capacitor C 2, resistance R 1 and resistance R 2, the earth terminal of integrated circuit (IC) 1 connects the control voltage end of integrated circuit (IC) 1 through capacitor C 2, one end of the triggering termination capacitor C 1 of integrated circuit (IC) 1 and an end of resistance R 1, the other end contact of capacitor C 1 is signaled, another termination power of resistance R 1, the termination power that resets of integrated circuit (IC) 1, the discharge end of the threshold value termination integrated circuit (IC) 1 of integrated circuit (IC) 1 and an end of resistance R 2, another root cable grounding, another termination power of resistance R 2.

The utility model adopts technique scheme, have the following advantages: utilize monostable circuit and control circuit to cooperate breakpoint to detect in real time to cable, judge the breakpoint distance, only need just can monitor to standby external cable through simple setting, when cable is cut or break down, can measure the distance of breakpoint of cable rapidly, the telephone number of dialing prior storage simultaneously carries out audio alert, for the automatic detection of cable provides method fast and effectively.

The utility model is described in further detail below in conjunction with drawings and Examples.

Description of drawings

Accompanying drawing 1 is the circuit block diagram of detection alarm instrument among the utility model embodiment;

Accompanying drawing 2 is the circuit theory diagrams of monostable circuit among the utility model embodiment;

Accompanying drawing 3 is the circuit theory diagrams of telephone interface circuit among the utility model embodiment;

Accompanying drawing 4 is the circuit theory diagrams of dial-up circuit among the utility model embodiment;

Accompanying drawing 5 is the circuit theory diagrams of bell flowing detecting circuit among the utility model embodiment.

Among the figure,

The 1-control circuit, 2-monostable circuit, 3-dial-up circuit, 4-telephone interface circuit, 5-bell flowing detecting circuit, 6-R232 interface circuit, 7-channel selection circuit, 8-external cable interface circuit, 9-recording and playing circuit.

Embodiment

Embodiment, as shown in Figure 1, Monostable circuit of automatic detection warning instrument for communication cable breakpoint comprises control circuit 1, monostable circuit 2, dial-up circuit 3, telephone interface circuit 4, bell flowing detecting circuit 5, R232 interface circuit 6, channel selection circuit 7, external cable interface circuit 8 and the recording and playing circuit 9 of electrical connection.

As shown in Figure 2, a pair of cable has only drawn among the figure, monostable circuit 2 comprises integrated circuit (IC) 1, capacitor C 1, capacitor C 2, resistance R 1 and resistance R 2, integrated circuit (IC) 1 is 555 integrated circuit, the earth terminal of integrated circuit (IC) 1 meets the control voltage end CVOLT of integrated circuit (IC) 1 through capacitor C 2, the trigger end TRIG of integrated circuit (IC) 1 connects an end of capacitor C 1 and an end of resistance R 1, the other end contact of capacitor C 1 is signaled, another termination power of resistance R 1, the reset terminal R of integrated circuit (IC) 1 connects power supply, the threshold value end THR of integrated circuit (IC) 1 connects the discharge end DIS of integrated circuit (IC) 1 and an end of resistance R 2, the threshold value end THR of integrated circuit (IC) 1 connects a cable through external cable interface circuit 8, another root cable grounding, another termination power of resistance R 2.

After the cable detection power on circuitry,, be equivalent to its threshold value end THR and discharge end DIS by the equivalent capacity C3 ground connection between cable, thereby constituted monostable circuit 555 integrated circuit.This moment is if send the trigger end TRIG of a low pulse signal to 555 integrated circuit by control circuit 1, will trigger out a high level pulse signal at the output terminal Q of 555 integrated circuit, detect the duration T s (Ts=1.1*C3*R2 second) of this high level by control circuit 1, and should preserve by time initial value Ts.During operate as normal, control circuit 1 scan round, and the duration of detected high level, Ts compares with initial value, if identical, then continues scan round.When line failure, when promptly the duration of detected high level and Ts are inequality, by control circuit 1 computational scheme electric capacity, the capacity C 3=Ts/1.1*R2 of capacitor C 3.This value again and be kept at the proof test value contrast of the cable length of control circuit 1 storage can be judged the distance of disconnected cable exactly then.

As shown in Figure 3, telephone interface circuit 4 comprises amplifying circuit and trigger circuit, amplifying circuit comprises operational amplifier IC2, operational amplifier IC3, resistance R 3, resistance R 4, resistance R 5, resistance R 6, resistance R 7, capacitor C 4, capacitor C 5, capacitor C 6 and capacitor C 7, the in-phase input end ground connection of operational amplifier IC2, the end of the inverting input connecting resistance R3 of operational amplifier IC2, one end of resistance R 4 and an end of resistance R 5, the other end of resistance R 3 connects the AUD sound signal through capacitor C 4, the other end of resistance R 4 connects dial-up circuit 3 through capacitor C 5, the output terminal of another termination operational amplifier IC2 of resistance R 5, the output terminal of operational amplifier IC2 is through the capacitor C 6 of series connection, resistance R 6 connects the inverting input of operational amplifier IC3, the in-phase input end ground connection of operational amplifier IC3, the inverting input of operational amplifier IC3 connects the output terminal of operational amplifier IC3 through resistance R 7, and the output terminal of operational amplifier IC3 is through capacitor C 7 contact Power Generation Roads.

Trigger circuit comprise triode Q1, isolating transformer T, relay J, diode V1, diode V2, diode V3, diode V4 and diode V5, diode V2, diode V3, diode V4 and diode V5 form full bridge rectifier, one termination capacitor C7 of isolating transformer T primary coil, the other end ground connection of isolating transformer T primary coil, an input end of one termination full bridge rectifier of isolating transformer T secondary coil, the other end of isolating transformer T secondary coil connects another input end of full bridge rectifier through the normal open switch K of relay J, the base stage connection control circuit 1 of triode Q1, the grounded emitter of triode Q1, the collector of triode Q1 connects the positive pole of diode V1, the negative pole of diode V1 connects power supply, and the coil of relay J is in parallel with diode V1.

When detecting when disconnected cable occurring, control circuit 1 is output as high level, makes triode Q1 conducting, the relay J adhesive; The dtmf signal that while dial-up circuit 3 sends is added on the isolating transformer T after operational amplifier IC2 and operational amplifier IC3 amplification, secondary, full bridge rectifier by isolating transformer T are added to external telephone wire TP1, TP2 end, thereby realize dialing of alarm call.Behind the other side's off-hook, the voice signal of warning is also through passing to outside line after operational amplifier IC2 and the operational amplifier IC3 amplification.

As shown in Figure 4, dial-up circuit 3 comprises integrated circuit (IC) 4, capacitor C 8, capacitor C 9, crystal oscillator G, the model of integrated circuit (IC) 4 is the dtmf signal generator of HT9200A, crystal oscillator G is connected between two crystal oscillator incoming ends of integrated circuit (IC) 4, capacitor C 8, capacitor C 9 and crystal oscillator G form the 3.58MHz crystal oscillator, the end of crystal oscillator G is through capacitor C 8 ground connection, the other end of crystal oscillator G is through capacitor C 9 ground connection, the chip selection signal input end CS of integrated circuit (IC) 4, serial signal synchronous input end SK and serial signal input end DATA connection control circuit 1, the power supply positive input termination power supply of integrated circuit (IC) 4, the answer the call capacitor C 5 of interface circuit 4 of the dtmf signal output terminal of integrated circuit (IC) 4, the power-input end grounding of integrated circuit (IC) 4.Adopt dtmf signal generator, use the 3.58MHz crystal oscillator, this chip has characteristics such as low-power consumption, total harmonic distortion be low, dtmf signal generator can be produced 16 kinds of two-frequency signals and 8 kinds of simple signals and be exported to telephone interface circuit 4 by the dtmf signal output terminal by control circuit 1 control, thereby realizes dialing.

As shown in Figure 5, bell flowing detecting circuit 5 comprises integrated circuit (IC) 5, resistance R 8, resistance R 9, resistance R 10, capacitor C 10, capacitor C 11, capacitor C 12 and photoelectrical coupler OC, the model of integrated circuit (IC) 5 is the ring detection chip of LS1240,1 pin and 8 pin of integrated circuit (IC) 5 are respectively the ringing-current input end, 2 pin are earth terminal, 3 pin are oscillation frequency setting-CSET end, 4 pin are oscillation frequency setting-RSET end, 5 pin are output terminal, 7 pin are the rectifying and wave-filtering end, 1 pin of integrated circuit (IC) 5 is through the resistance R 8 and the capacitor C 10 line TP1 that answers the call of series connection, the 8 pin line TP2 that answers the call, 7 pin connect an end of capacitor C 11, and 3 pin connect an end of capacitor C 12, the end of 4 pin connecting resistance R9,2 pin connect the other end of capacitor C 11, the other end of the other end of capacitor C 12 and

resistance R

9,5 pin of integrated circuit (IC) 5 connect the input end of photoelectrical coupler OC, another input end grounding of electric coupler OC, the output terminal connection control circuit 1 of photoelectrical coupler OC through resistance R 10.

When disconnected cable appears in cable, dial the police emergency number, after the other side's off-hook is answered, again during clawback, 70-120V, the ringing signal of 25Hz can be added to the ring detection chip through C10 after straight, R8 current limliting, portion exports from 5 pin by the oscillator and the amplifier generation ringdown of inside behind rectifying and voltage-stabilizing within it, exports digital signal to control circuit 1 through photoelectrical coupler again, after control circuit 1 detects, stop to report to the police.

Claims

1. Monostable circuit of automatic detection warning instrument for communication cable breakpoint, it is characterized in that: described alarm comprises the control circuit (1) and the monostable circuit (2) of electrical connection, monostable circuit (2) comprises integrated circuit (IC) 1, capacitor C 1, capacitor C 2, resistance R 1 and resistance R 2, the earth terminal of integrated circuit (IC) 1 connects the control voltage end of integrated circuit (IC) 1 through capacitor C 2, one end of the triggering termination capacitor C 1 of integrated circuit (IC) 1 and an end of resistance R 1, the other end contact of capacitor C 1 is signaled, another termination power of resistance R 1, the termination power that resets of integrated circuit (IC) 1, the discharge end of the threshold value termination integrated circuit (IC) 1 of integrated circuit (IC) 1 and an end of resistance R 2, another root cable grounding, another termination power of resistance R 2.