CN203259808U - Circuit breaker characteristic detection test bed automatic-carry timer - Google Patents

Abstract

The utility model relates to a circuit breaker characteristic detection test bed automatic-carry timer which comprises a single chip microcomputer, a small power bare board, a three-end voltage-stabilized power source modulator, a four-digit nixie tube and a crystal oscillator reset circuit. The single chip microcomputer can control corresponding input and output ports of the nixie tube for digital display to be connected with pins of the nixie tube, the two ends of a reset button are connected to the RESET pin and the GND pin of the single chip microcomputer respectively and the two ends of a second capacitor respectively, the two ends of a pull-up resistor are connected to the 5V pin and the RESET pin of the single chip microcomputer respectively, the two ends of a first capacitor are connected to the 5V pin and the GND pin of the single chip microcomputer respectively, the two ends of a crystal oscillator are connected to the XTAL1 pin and the XTAL2 pin of the single chip microcomputer respectively, and the two ends of the crystal oscillator are grounded through a third capacitor and a fourth capacitor respectively. According to the timer, decimal points can be automatically shifted, the four-digit nixie tube can display the timekeeping time of more than two hours and forty minutes, and the time can be corrected to 0.001 second.

Description

Circuit breaker characteristic detects testing table automatic carry timer

Technical field

The utility model belongs to a kind of breaker test stand timer, particularly relates to a kind of circuit breaker characteristic and detects testing table automatic carry timer.

Background technology

There is following defective in the timer that uses at present known home market electric product detection testing table: the charactron figure place that is used for showing many (being generally five-digit number code pipe), but not wide (the longest timing 999.99S of displaying time scope, also less than is 17 minutes), precision lower (can only be accurate to 0.01S) is not suitable for some electric products control occasion that accuracy requirement is higher at the trial, the timing time requirement is long.If adopt original design proposal will increase the figure place that the timing time scope just must increase charactron, the charactron figure place increases then needs to take more single-chip processor i/o mouth, also need to use instead larger single-chip microcomputer in case the I/O mouth is not enough, and the drive current that need to add every section diode in the triode logarithmic code pipe after the charactron figure place increases in order to reach normal display brightness in circuit amplifies, so undoubtedly so that the volume of timer is larger.

Summary of the invention

The utility model provides a kind of timing time that shows to reach two hours more than 40 minutes circuit breaker characteristic detection testing table automatic carry timer for solving the technical matters that exists in the known technology.

The utility model for the technical scheme that solves the technical matters that exists in the known technology and take is: it includes single-chip microcomputer, small power supply bare board, three-terminal voltage-stabilizing power supply modulator, and it also includes four positions and selects pin and eight ends to select common cathode group of four figures pipe and the crystal oscillator reset circuit of pin; Comprise on the described group of four figures pipe that four positions select pin and eight sections to select pin, each charactron all is made of eight sections diodes, and described single-chip microcomputer can be controlled each pin of corresponding input/output port and charactron that the charactron numeral shows and be connected; Receive respectively on single-chip microcomputer RESET and two pins of GND at the two ends of reset button, and the two ends of second electric capacity, receive respectively on single-chip microcomputer 5V and two pins of RESET at the two ends of pull-up resistor, receive respectively on single-chip microcomputer 5V and two pins of GND at the two ends of the first electric capacity, receive respectively on single-chip microcomputer XTAL1 and two pins of XTAL2 at the two ends of crystal oscillator, and these two ends are respectively by the 3rd, the 4th capacity earth.

Advantage and the good effect that the utlity model has are: the radix point of timer can carry out automatic shift, only just can show with group of four figures pipe to reach two hours more than 40 minutes timing time, and can be accurate to 0.001 second

Description of drawings

Fig. 1 is the single-chip microcomputer pinouts of the utility model tool;

Fig. 2 is the charactron display part circuit theory diagrams of the utility model tool;

Fig. 3 is crystal oscillator and the reset portion parallel circuit schematic diagram of the utility model tool;

Fig. 4 is the power unit schematic diagram of the utility model tool;

Fig. 5 is the control program process flow diagram of the utility model tool.

Embodiment

For further understanding summary of the invention of the present utility model, Characteristic, hereby exemplify following examples, and cooperate accompanying drawing to be described in detail as follows:

As shown in Figure 1, 2, Q, B, S, the G(that pin PA3, the PA6 of single chip computer AT mega16, PA7, PB7 receive respectively charactron is kilobit, hundred, ten, individual position) these four positions select pin, be used for controlling group of four figures pipe whether electric; Pin PC6, the PB1 of single chip computer AT mega16, PB3, PB4, PB2, PC4, PB5, PA4 receive respectively a, b, c, d, e, f, these eight sections of g, dp of charactron and select pin, be used for controlling eight sections diodes whether electric.The light on and off that program among the single chip computer AT mega16 can be controlled the first seven section diode form digital " 0 " to " 9 ", the dp section is radix point, select to such an extent that whether electricly select to allow who radix point effectively show by controlling four positions, the demonstration of charactron is controlled in the switching of the high-low level of the input/output port by control single chip computer AT mega16 like this.

As shown in Figure 4, the input termination 220V AC power of the small power supply bare board SMPS that the output direct current is 12 volts, the GND of its output terminal connects respectively the GND of the three-terminal voltage-stabilizing power supply modulator 78L05 that exports 5 volts of direct currents and the negative pole of electrochemical capacitor C5, and the extension line of GND is linked into the GND pin of single chip computer AT mega16, the negative electrode of voltage stabilizing diode D1 meets the 12V of small power supply bare board SMPS output terminal, its anode connects the input end of three-terminal voltage-stabilizing power supply modulator 78L05, the output terminal of three-terminal voltage-stabilizing power supply modulator 78L05 links to each other with the anode of electrochemical capacitor C5, and its extension line is linked into the VCC pin of single chip computer AT mega16.

As shown in Figure 3, receive respectively on the RESET and two pins of GND of single chip computer AT mega16 at the two ends of reset button SW, and with these two two ends that pin is received respectively capacitor C 2, receive respectively on the 5V and two pins of RESET of single chip computer AT mega16 at the two ends of pull-up resistor R1, and the two ends of capacitor C 1 are received respectively the interference in the filter out power on the 5V of single chip computer AT mega16 and two pins of GND, guaranteed that VCC's is stable.Receive respectively on the XTAL1 and two pins of XTAL2 of single chip computer AT mega16 at the two ends of crystal oscillator Y, and these two ends are respectively by capacitor C 3, C4 ground connection.

The control register clock selecting position of single chip computer AT mega16 is set to 64 frequency divisions, owing to adopt the crystal oscillator of 12.8MHz, so the time of every note one number of data register is (64/12800) millisecond, namely data register remembers that the corresponding timing time of 200 numbers is 1 millisecond.Namely 0000 arrive FFFF for 16 data register TCNT1(, altogether can count 65536 numbers) zero clearing, then the register automatic counting enters after writing all over and overflows interruption, at this moment the corresponding real time is 327.68 milliseconds, then return data register zero clearing and repeat above-mentioned flow process.Record enters the number of times of interruption, and then (aa represents timing time in the computing formula to calculate total timing time: aa=327.68*s+TCNT1* (64/12800), the s representative enters the number of times of interruption, and TCNT1 represents the number of register numeration, and unit is millisecond).The radix point of kilobit was effective when timing time was not more than 9999 milliseconds, and charactron showed 0.001 second when namely timing time was 1 millisecond, and charactron showed 0.010 second when timing time was 10 milliseconds; Timing time is greater than 9999 milliseconds and when being not more than 99999 milliseconds, and hundred radix point is effective, 4-digit number before showing, and charactron showed 12.34 seconds when namely timing time was 12345 milliseconds; Timing time is greater than 99999 milliseconds and when being not more than 999999 milliseconds, and ten radix point is effective, 4-digit number before showing, and charactron showed 123.4 seconds when namely timing time was 123456 milliseconds; Timing time is greater than 999999 milliseconds and when being not more than 9999999 milliseconds, and four radix point are completely without effect, 4-digit number before showing, and charactron showed 1234 seconds when namely timing time was 1234567 milliseconds.So just, realize the automatic shift of radix point, thereby enlarged timing time scope to 9999 second, namely 2 hours 46 minutes 40 seconds, can be used for the occasion that the requirement timing time is long and accuracy requirement is higher.

Control of the present utility model is finished according to the following steps:

1. judge whether to begin timing, if as then carry out step 2, continue to judge if not return;

2. startup timer, it is 64 frequency divisions that the clock selecting position is set, the beginning timing;

3. the calculating timing time determines display precision according to the time size;

4. demonstration timing time;

Judge whether to stop timing, if as then keeping timing time, if not return step 3.

Claims (1)

1. a circuit breaker characteristic detects testing table automatic carry timer, it includes single-chip microcomputer, small power supply bare board, three-terminal voltage-stabilizing power supply modulator, it is characterized in that: also include four positions and select pin and eight ends to select common cathode group of four figures pipe and the crystal oscillator reset circuit of pin; Comprise on the described group of four figures pipe that four positions select pin and eight sections to select pin, each charactron all is made of eight sections diodes, and described single-chip microcomputer can be controlled each pin of corresponding input/output port and charactron that the charactron numeral shows and be connected; Receive respectively on single-chip microcomputer RESET and two pins of GND at the two ends of reset button, and the two ends of second electric capacity, receive respectively on single-chip microcomputer 5V and two pins of RESET at the two ends of pull-up resistor, receive respectively on single-chip microcomputer 5V and two pins of GND at the two ends of the first electric capacity, receive respectively on single-chip microcomputer XTAL1 and two pins of XTAL2 at the two ends of crystal oscillator, and these two ends are respectively by the 3rd, the 4th capacity earth.

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