CN210128997U

CN210128997U - Power grid detector and socket provided with same

Info

Publication number: CN210128997U
Application number: CN201920816624.9U
Authority: CN
Inventors: 王平
Original assignee: Ningbo Yun Qing Electronic Technology Co Ltd
Current assignee: Ningbo Yun Qing Electronic Technology Co Ltd
Priority date: 2019-06-01
Filing date: 2019-06-01
Publication date: 2020-03-06
Anticipated expiration: 2029-06-01

Abstract

A power grid detector and a socket provided with the same belong to the technical field of detectors. The power grid detector comprises a shell and a plug; a circuit is arranged in the shell; the circuit comprises an operational amplifier (U1) and a filter; the filter comprises a filter A and a filter B; the filter A comprises a capacitor CB2 and a resistor R3; the filter B comprises a capacitor C5 and a resistor R4; one side of the operational amplifier (U1) collects external noise and radiation signals through a signal collection end (INPUT), the other side of the operational amplifier is connected with a measurement chip (U2), and the measurement chip (U2) is connected with a display end (DISP 1). More than 1 group of power jacks are arranged on the shell. The utility model has the advantages that: through simple circuit design, the production cost of the detector is reduced, whether the electromagnetic field of the power grid in our living environment exceeds the standard or not can be known in time, and then our power grid environment is improved, and the index beneficial to health is improved.

Description

Power grid detector and socket provided with same

Technical Field

The utility model relates to a detector, in particular to electric wire netting detector and ann have electric wire netting detector's socket.

Background

With the development of economy, various electronic and electric devices (such as induction cookers, microwave ovens, copiers, washing machines and dish washing machines) are increased, the wiring reasonableness of the power grid and the operation of high-power electric devices cause high-frequency component signals with short duration and high voltage to exist in the power grid.

These are electromagnetic oscillation sources which, together with disturbances occurring during operation of the device, form electromagnetic fields which can be harmful to human tissue. These fields are invisible to the naked eye, but the long term accumulation is very harmful to the human body. One existing method for measuring high-frequency component signals of a power transmission line is through a spectrum analyzer. Such a measuring instrument is not only expensive, but also requires a professional to operate.

Ideally, it would be desirable to have a simple device for measurement that can be used without special training.

SUMMERY OF THE UTILITY MODEL

In order to solve the problem that the measurement transmission line high frequency component signal method is complicated among the prior art, with high costs, the utility model provides a power grid detector, it reduces detector manufacturing cost through simple circuit design, more can know immediately whether the electromagnetic field of our living environment's electric wire netting exceeds standard, and then our power grid environment of modified promotes and does benefit to healthy index.

The utility model discloses the technical scheme who adopts as follows: a power grid detector comprises a shell and a plug; a circuit is arranged in the shell; the circuit comprises an operational amplifier (U1), the circuit further comprises a filter; the filter comprises a filter A and a filter B; the filter A comprises a capacitor CB2 and a resistor R3; the filter B comprises a capacitor C5 and a resistor R4; one side of the operational amplifier (U1) collects external noise and electromagnetic field through a signal collection end (INPUT), and the other side is connected with a measurement chip (U2). The measuring chip (U2) outputs display data to a display terminal (DISP 1).

The measuring chip (U2) comprises a D/A conversion circuit, a reference source, a clock system, a seven-segment decoder and a display driver.

The measuring chip (U2) is ICL7106, ICL7107 or a singlechip.

The display terminal (DISP1) is LCD, nixie tube, OLED screen, color screen or LED.

The power grid detector is provided with an independent switch A for switching on and off the power grid detector.

The socket is provided with a power grid detector and comprises a power grid detector, a plug and a power supply jack; the power grid detector comprises a shell; the casing is internally provided with a circuit, and the casing is provided with more than 1 group of power jacks. (the socket and the power jack are prior art and will not be described in detail).

The power supply jack is provided with an independent switch B for switching on and off the power supply jack.

The power grid detector can also be installed in a wall socket.

The working principle is as follows:

the circuit contains a filter which is able to divide the frequency of the signal of the transmission line. For example, a power line signal with a frequency of 50-60Hz, and a signal more representative of the high frequency characteristic can be output through the frequency division of the filter. The signal output by the filter is input to an operational amplifier U1 with a feedback loop, which allows the signal output by the amplifier to be rectified and maintains an average output. The amplifier output is then processed by a common measurement chip or MCU and output to the display (DISP 1).

The utility model provides a beneficial effect that technical scheme brought is:

the utility model provides a power grid detector, it is through simple circuit design, and lower cost more can know immediately whether the electromagnetic pollution coefficient of our living environment's electric wire netting exceeds standard, and then modified our electric wire netting environment, promotes and does benefit to healthy index.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic circuit diagram of embodiment 1 of the present invention;

fig. 2 is an external view of a power grid tester according to embodiment 1 of the present invention;

fig. 3 is an appearance diagram of a socket with a power grid tester according to embodiment 2 of the present invention.

Description of reference numerals: casing 1, display end (DISP1)2, power jack 3, plug 4.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

Example 1:

as shown in fig. 1 and 2, the power grid detector comprises a shell 1 and a plug 4; a circuit is arranged in the shell 1; the circuit comprises an operational amplifier (U1), the circuit further comprises a filter; the filter comprises a filter A and a filter B; the filter A comprises a capacitor CB2 and a resistor R3; the filter B comprises a capacitor C5 and a resistor R4; one side of the operational amplifier (U1) collects external noise and electromagnetic field through a signal collection end (INPUT), and the other side is connected with a measurement chip (U2). The measuring chip (U2) outputs display data to a display terminal (DISP1) 2.

The measuring chip (U2) is ICL 7106.

The display terminal (DISP1)2 is an LED.

The grid tester is equipped with an independent switch a (not shown in the figure). The power grid detector is used for controlling the on and off of the power grid detector.

The working principle is as follows:

the circuit contains a filter which is able to divide the frequency of the signal of the transmission line. For example, a power line signal with a frequency of 50-60Hz, and a signal more representative of the high frequency characteristic can be output through the frequency division of the filter. The signal output by the filter is input to an operational amplifier U1 with a feedback loop, which allows the signal output by the amplifier to be rectified and maintains an average output. The amplifier output is then processed by a common measurement chip or MCU and output to the display (DISP1) 2.

Detailed description:

signals in the power transmission line include a fundamental frequency signal, a high frequency component signal, and the like. Our present detection is directed to the high frequency part; we need to substantially eliminate the fundamental frequency signal, leaving a high frequency signal. Then the frequency is divided and corrected, and a stable average value is output and displayed by a common display device. The portion of the display device that is of interest is the value that effectively represents the power line power pollution without the need to detect components at each frequency.

The following part analyzes the circuit in detail, the circuit is not expensive to build, and the whole circuit part can be integrated into a common socket.

The circuit principle is explained as follows:

the circuit of the attached figure 1 is as follows: INPUT represents mains INPUT. First, the Alternating Current (AC) terminal signal is passed through a voltage divider formed by resistors R1 and R12 to reduce the potential of the AC terminal input, for example, to 2% of the original potential. The voltage divider used in fig. 1, which is composed of resistors, may also be formed by capacitors or other voltage dividing circuits or may sometimes be omitted directly.

As mentioned above, the potential of 2/% of the original AC terminal is applied across resistor R1 through a voltage divider connected to a filter capable of substantially eliminating the fundamental frequency signal of the transmission line. Typically this filter (RC filter) has a high impedance for low frequency signals, e.g. 50Hz to 60Hz, and a low impedance for high frequency signals. The circuit of fig. 1 includes two RC filters, filter a and filter B; the filter A consists of a capacitor CB2 and a resistor R3; the filter B is composed of a capacitor C5 and a resistor R4. The filter can basically eliminate the fundamental frequency signal of the power line and allow the high-frequency signal to pass through.

The filter output voltage is equal to the voltage across resistor R4, which is connected to capacitor C7. C7 is a capacitor with a very small capacitance that provides a very high impedance to divide the signal coming from the filter. The divided signal is fed to the inverting terminal of an amplifier U1(TL07CP), the non-inverting terminal of which is common to the lower terminal of the Alternating Current (AC) terminal.

A pair of diodes are connected in parallel in the reverse direction at the forward end and the reverse end of the amplifier, and play a role of voltage stabilization, for example, when a voltage value exceeding a rated value is added at the two ends of the diode, the diode is broken down, and the voltage at the two ends is ensured to be stabilized at 0.8V. Thereby protecting the amplifier and the instrumentation of the right circuit from damage caused by over-voltage drive from the ac side.

The output and inverting circuits of amplifier U1 form a feedback loop. In this feedback loop, a diode D6 is connected in series with a parallel circuit consisting of a capacitor C8 and a resistor R5, and then another diode D7 is connected directly in reverse with a diode D6 to the reverse terminal and output terminal of the amplifier.

In this feedback loop for the average value of the output signal, the values of the resistor R5 and the capacitor C8 are specifically set so that the amplifier can successfully convert an ac signal to a single dc signal. In addition, considering that the capacitor C8 is connected to the capacitors CB2, C5, C7, the capacitor C8 determines practically all high frequency signals received.

Diode D6 and diode D7 act to rectify the reverse pulse of the amplifier and output a forward going pulse. The dc signal value output by the amplifier is thus the offset value of the signal applied to its inverting input.

The output signal of the amplifier U1 is connected into a common measuring chip U2, and U2 is ICL 7106; the display comprises an A/D, D/A conversion circuit, a reference source, a clock system, a seven-segment decoder and a display driver.

The U2 outputs display data to the display terminal (DISP1)2 through the internal display driver.

In practical operation, an ac signal from the ac terminal is divided by the voltage divider to become 2% of the original value, and then the divided signal is coupled to a two-stage high-pass filter composed of capacitors CB2 and C5 and resistors R3 and R4. The filter has high impedance to the transmission line fundamental frequency of 50-60Hz through the special setting of the resistance capacitance value, so that the transmission line fundamental frequency signal is basically eliminated, and only a high-frequency signal is left. The signal passing through the filter is divided by the input capacitor C7, and the current passing through the capacitor C7 is C × dV/dt because the capacitance of the capacitor C7 is small. Due to the field effect transistor as an input stage of the amplifier, the amplifier possesses a large input impedance. In the present circuit, the amplifier can have a bandwidth of 100KHz or more. The feedback loop formed by the capacitor C8, the resistor R5, and the diodes D6 and D7 can rectify the input signal at the input of the amplifier to make a smooth output as a dc signal. And then the display is driven to display through the processing of the measuring chip.

So far, a measuring circuit capable of measuring electric power pollution of a power transmission line has been introduced. The circuit can be constructed at low cost.

The power grid detector using method comprises the following steps:

when the plug 4 of the detector is inserted into a power supply of an environment to be measured, the LED on the detector displays the current radiation value. Numerical units mSv, numerical display range: 1mSv-1999mSv, and if the value exceeds 1999mSv, the left side of the screen is shown as "1".

Example 2:

as shown in fig. 3, the socket provided with the power grid detector comprises a power grid detector, a plug 4 and a power jack 3; the power grid detector comprises a shell 1; a circuit is installed in the

shell

1, and 2 groups of power jacks 3 are arranged on the shell 1. (the socket and the power jack are prior art and will not be described in detail).

The power jack is provided with a separate switch B (not shown). Used for controlling the on and off of the power supply jack.

The power grid tester was the same as in example 1.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. A power grid detector comprises a shell and a plug; the method is characterized in that: a circuit is arranged in the shell; the circuit comprises an operational amplifier (U1), the circuit further comprising a filter; the filter comprises a filter A and a filter B; the filter A comprises a capacitor CB2 and a resistor R3; the filter B comprises a capacitor C5 and a resistor R4; one side of the operational amplifier (U1) collects external noise and electromagnetic field through a signal collection end (INPUT), the other side of the operational amplifier is connected with a measurement chip (U2), and the measurement chip (U2) outputs display data to a display end (DISP 1).

2. The power grid tester according to claim 1, wherein: the measuring chip (U2) comprises a D/A conversion circuit, a reference source, a clock system, a seven-segment decoder and a display driver.

3. The grid tester according to claim 2, wherein: the measuring chip (U2) is ICL7106, ICL7107 or a singlechip.

4. The power grid tester according to claim 1, wherein: the display terminal (DISP1) is LCD, nixie tube, OLED screen, color screen or LED.

5. The power grid tester according to claim 1, wherein: the power grid detector is provided with an independent switch A.

6. The socket provided with the power grid detector according to claim 1 is characterized in that: the socket comprises a power grid detector, a plug and a power supply jack; the power grid detector comprises a shell; the casing is internally provided with a circuit, and the casing is provided with more than 1 group of power jacks.

7. The socket of the electric network detector according to claim 6, wherein: the power supply jack is provided with an independent switch B.