CN201828236U

CN201828236U - Cable testing circuit

Info

Publication number: CN201828236U
Application number: CN2010205760751U
Authority: CN
Inventors: 林禹鹏
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-10-26
Filing date: 2010-10-26
Publication date: 2011-05-11
Anticipated expiration: 2020-10-26

Abstract

The utility model relates to the field of testing circuits, in particular to a cable testing circuit. A cable switch switching circuit is connected with an integral charge and discharge circuit and a voltage comparison circuit respectively; and two output signals are respectively connected to a single chip microcomputer control circuit which outputs a display circuit. In the cable testing circuit, the charge and discharge period is utilized by a voltage integral circuit, logical operation is controlled by a single chip microcomputer, a plurality of cables can be measured simultaneously; the length of the cable, breaking distance and short-circuit fault and the like can be measured accurately; and the cables can be judged and displayed accurately. The cable testing circuit is simple in structure, economical and practical and is a measuring instrument circuit device for measuring and maintaining.

Description

A kind of cable test circuit

Technical field

The utility model relates to the test circuit field, particularly relates to a kind of cable test circuit.

Background technology

At present, communication or power cable are widely used in communication or power-supply unit, but measure length and lack survey instrument, and the method for check to lay the whether short circuit of distance cable far away, misconnection, missing is to adopt multimeter, contact pin and lead to test, when checking cable, need two staff at least; If the heart yearn quantity of tested cable is bigger, to expend a large amount of time, be easy to cause the situation of not exclusively test to take place, there is potential safety hazard, in addition, the testing result of tested each heart yearn of cable adopts manual record, also has the possibility of makeing mistakes in recording process, checks and accepts for construction maintenance, buying and brings inconvenience.

The utility model content

The purpose of this utility model provides a kind of accurate measurement cable length and breaking distance, short trouble etc., cable is accurately judged the cable test circuit of demonstration.

The technical scheme that the utility model adopted is such: a kind of cable test circuit, connect integration respectively by the cable switch commutation circuit and charge and discharge circuit and voltage comparator circuit, two output signals are connected respectively to single chip machine controlling circuit, single chip machine controlling circuit output display circuit.

Cable end piece A short circuit is represented to measure first via cable, supply voltage is connected to the 5th pin of analog switching circuit U4 through resistance R 4 dividing potential drops, the external stake resistance R of the 3rd pin of analog switching circuit U4, the 3rd pin by analog switching circuit U4 is an output terminal, divide two-way to connect, one the road is connected to the 7th pin of time base circuit U3, time base circuit U3 shunt capacitance C1 forms integration and charges and discharge circuit, C1 is charged, the 2nd foot control system output of time base circuit U3 is connected to the 39th pin height of single chip machine controlling circuit U1, electronegative potential, another road of the 3rd pin output terminal of analog switching circuit U4 is connected to voltage comparator U5A, the 3rd pin of U5B, the 5th pin, carry out two grades of voltage ratios, respectively by voltage comparator U5A, the 1st pin of U5B and the 7th pin output high level, be connected to the 36th pin of single chip machine controlling circuit U1, the height of the 37th pin, electronegative potential, through the output of single chip machine controlling circuit U1 internal logic s operation control, by single chip machine controlling circuit U1 the 32nd, 33,34,35 pin respectively with display circuit U2 the 3rd, 4,5,6 pin connect to form data transfer control circuit.

By adopting the aforementioned techniques scheme, the beneficial effects of the utility model are: this cable test circuit is knitted the parallel circuit utilization by voltage and is discharged and recharged the cycle, through the Single-chip Controlling logical operation, can measure many cables simultaneously, accurately measure cable length and breaking distance, short trouble etc., cable is accurately judged demonstration, economical and practical, be the surveying instrument circuit arrangement of measuring, safeguarding.

Description of drawings

Fig. 1 is the frame assumption diagram of the utility model embodiment;

Fig. 2 is the circuit theory diagrams of the utility model embodiment.

Embodiment

Further specify the utility model below in conjunction with the drawings and specific embodiments.

As shown in Figure 1 and Figure 2, a kind of cable test circuit is connected respectively by cable switch commutation circuit 1 that integration charges and discharge circuit 2 and voltage comparator circuit 5, two output signals are connected respectively to single chip machine controlling circuit 3, single chip machine controlling circuit 3 output display circuits 4.

Cable end piece A short circuit is represented to measure first via cable, supply voltage is connected to the 5th pin of analog switching circuit U4 through resistance R 4 dividing potential drops, the external stake resistance R of the 3rd pin of analog switching circuit U4, avoid exporting unsettled generation false positive signal because of its 3rd pin, the 3rd pin by analog switching circuit U4 is an output terminal, divide two-way to connect, one the tunnel connects the 7th pin of time base circuit U3, time base circuit U3 shunt capacitance C1 forms integration and charges and discharge circuit, C1 is charged, charge cycle is limited the control switching cycle of analog switching circuit U4 by single chip machine controlling circuit U1, the 2nd foot control system output of time base circuit U3 is connected to the 39th pin height of single chip machine controlling circuit U1, electronegative potential, another road of the 3rd pin output terminal of analog switching circuit U4 is connected to voltage comparator U5A, the 3rd pin of U5B, the 5th pin, carry out two grades of voltage ratios, respectively by voltage comparator U5A, the 1st pin of U5B and the 7th pin output high level, be connected to the 36th pin of single chip machine controlling circuit U1, the height of the 37th pin, electronegative potential, export through single chip machine controlling circuit U1 internal logic s operation control, by single chip machine controlling circuit U1 the 32nd, 33,34,35 pin respectively with display circuit U2 the 3rd, 4,5,6 pin connect to form data transfer control circuit, show current cable length and fault.

More than show and described ultimate principle of the present utility model and principal character and advantage thereof; the technician of the industry should understand; the utility model is not restricted to the described embodiments; that describes in the foregoing description and the explanation just illustrates principle of the present utility model; under the prerequisite that does not break away from the utility model spirit and scope; the utility model also has various changes and modifications; these changes and improvements all fall in claimed the utility model scope, and the claimed scope of the utility model is defined by appending claims and equivalent thereof.

Claims

1. cable test circuit, it is characterized in that: connect integration respectively by cable switch commutation circuit (1) and charge and discharge circuit (2) and voltage comparator circuit (5), two output signals are connected respectively to single chip machine controlling circuit (3), single chip machine controlling circuit (3) output display circuit (4).