CN212008735U - Non-contact intelligent electroscope for high-voltage power equipment - Google Patents

Abstract

The utility model discloses a non-contact intelligent electroscope for high voltage power equipment, including the casing, be provided with on the casing: the electric field induction antenna, the charging interface, the key panel, the indicator light and the loudspeaker are arranged on the key panel; a circuit board is arranged in the shell; the circuit board is provided with an MCU control module, an electric field detection circuit, a communication circuit, a power supply and battery management circuit, a key circuit, an indicator light circuit and a voice circuit; the electric field induction antenna is electrically connected with the input end of the MCU control module through the electric field detection circuit, the communication circuit is in communication connection with the MCU control module, the charging interface is electrically connected with the input end of the MCU control module through the power supply and the battery management circuit, the key panel is electrically connected with the input end of the MCU control module through the key circuit, the indicator lamp is electrically connected with the output end of the MCU control module through the indicator lamp circuit, and the loudspeaker is electrically connected with the output end of the MCU control module through the voice circuit; the utility model discloses can carry out non-contact to high tension switchgear's electrified state and detect.

Description

Non-contact intelligent electroscope for high-voltage power equipment

Technical Field

The utility model belongs to the technical field of power equipment, concretely relates to non-contact intelligent electroscope for high voltage power equipment.

Background

At present, the electric power enterprise all adopts the electricity testing handcart to carry out direct contact's the electricity of testing to the electric power equipment's such as high tension switchgear electricity testing work, and this kind of electricity testing handcart complex operation has brought following problem:

1) an insulation glove is required to be arranged on the electric isolation to carry out an electrified test, so that the operation time is prolonged;

2) the electricity testing handcart needs to be dragged to a maintenance position and pushed into the electricity testing handcart, and operation steps are added;

3) the partial handcart dragging needs large force, the back and forth pulling and pushing increases the operation difficulty of operators, the operation generally needs cooperation of a plurality of people, and meanwhile, the operation time is also increased.

Because the equipment has more work tasks of power failure under the common condition, the electricity testing preparation work is greatly influenced by the site, and the single person can not or is difficult to operate.

In conclusion, the traditional electricity testing handcart has the problems of time consumption, power consumption and complex operation in the electricity testing of the high-voltage switch cabinet, and the problem is more obvious particularly when the electricity testing handcart has multiple electricity testing tasks.

SUMMERY OF THE UTILITY MODEL

The utility model overcomes the deficiencies in the prior art, the technical problem who solves is: the utility model provides a non-contact intelligence electroscope for high voltage power equipment can carry out non-contact to the high tension switchgear and test the electricity, shortens and tests electric operating time, improves and tests electric efficiency.

In order to solve the technical problem, the utility model discloses a technical scheme be:

a non-contact intelligent electroscope for high-voltage power equipment, includes the casing, be provided with on the casing: the electric field induction antenna, the charging interface, the key panel, the indicator light and the loudspeaker are arranged on the key panel; a circuit board is arranged in the shell; the circuit board is provided with an MCU control module, an electric field detection circuit, a communication circuit, a power supply and battery management circuit, a key circuit, an indicator light circuit and a voice circuit; the electric field induction antenna is electrically connected with the input end of the MCU control module through the electric field detection circuit, the communication circuit is in communication connection with the MCU control module, the charging interface is electrically connected with the input end of the MCU control module through the power supply and the battery management circuit, the key panel is electrically connected with the input end of the MCU control module through the key circuit, the indicator lamp is electrically connected with the output end of the MCU control module through the indicator lamp circuit, and the loudspeaker is electrically connected with the output end of the MCU control module through the voice circuit.

Preferably, the MCU control module includes: a control chip U8, the electric field detection circuit includes an electric field sensor U7, the voice circuit includes: a voice processing chip U3 and a power amplifier chip U2; the TX end of the electric field sensor U7 is electrically connected with an electric field induction antenna, the VCC end of the electric field sensor U7 is connected with the VCC power output end of a power supply and battery management circuit, the SCL end of the electric field sensor U7 is connected with the SCL end of the control chip U8, and the SDA end of the electric field sensor U7 is connected with the SDA end of the control chip U8;

the BUSY end of the voice processing chip U3 is connected with the BUSY end of the control chip U8, the RST end of the voice processing chip U3 is connected with the RST end of the control chip U8, the DATA end of the voice processing chip U3 is connected with the DATA end of the control chip U8, the CLK end of the voice processing chip U3 is connected with the CLK end of the control chip U8, the P end of the voice processing chip U3 is connected with the INP end of the power amplification chip U2, the N end of the voice processing chip U3 is connected with the INN end of the power amplification chip U2, the CTRL end of the power amplification chip U2 is connected with the VCC power output end of the power supply and battery management circuit after being connected with a resistor R1 in series, the CTRL end of the power amplification chip U2 is connected with the CTRL end of the control chip U8, the Byp end of the U635 is connected with a capacitor C26 in series and then grounded, and the VOP end of the power amplification chip U2 is connected with a plug 5928, a plug pin of the N599 and a plug pin 599 of the, Pin 1 of a plug N5 and pin 3 of a plug N5 are connected, the other end of the capacitor C25 is grounded, the GND end of the power amplifier chip U2 is grounded, the VCC end of the power amplifier chip U2 is connected with the VCC power supply output end of the power supply and battery management circuit, the VON end of the power amplifier chip U2 is connected in series with an inductor FB2 and then connected with one end of a capacitor C27, pin 2 of the plug N4, pin 4 of the plug N4, pin 2 of the plug N5 and pin 4 of the plug N5, the other end of the capacitor C27 is grounded, pin 5 of the plug N4 is connected with pin 6 of the plug N4 and then grounded, and pin 5 of the plug N5 is connected with pin 6 of the plug N5 and then grounded; the loudspeaker comprises a first loudspeaker and a second loudspeaker, the voice circuit is electrically connected with the first loudspeaker through a plug N4, and the voice circuit is electrically connected with the second loudspeaker through a plug N5;

the key circuit key plug N3 is characterized in that a pin 1 of the key plug N3 is connected with a resistor R19 in series and then is connected with one end of a resistor R20, one end of a resistor R21, one end of a resistor R22, one end of a resistor R23 and a VCC power output end of a power supply and battery management circuit, the other end of the resistor R20 is connected with a pin 2 of the key plug N3, the other end of the resistor R21 is connected with a pin 3 of the key plug N3, the other end of the resistor R22 is connected with a pin 4 of the key plug N3, the other end of the resistor R23 is connected with a pin 5 of the key plug N3, and the key circuit is electrically connected with a button arranged on a key panel through a key plug N3;

the indicator light circuit includes: an indicator lamp D3, an indicator lamp D4, an indicator lamp D5, an indicator lamp D6, an indicator lamp D7, an indicator lamp D8 and an indicator lamp D9, wherein one end of the indicator lamp D3 is connected to an LED1 end of a control chip U8, one end of the indicator lamp D4 is connected to an LED2 end of the control chip U8, one end of the indicator lamp D5 is connected to an LED3 end of the control chip U8, one end of the indicator lamp D6 is connected to an LED4 end of the control chip U8, one end of the indicator lamp D7 is connected to an LED5 end of the control chip U8, one end of the indicator lamp D8 is connected to an LED6 end of the control chip U8, one end of the indicator lamp D9 is connected to an LED7 end of the control chip U8, and the other end of the indicator lamp D7 is connected to one end of a resistor R7, one end of a VCC power supply of the resistor R7, one end of the power supply of the resistor R7 and one end of the battery management circuit 7, the other end of the resistor R13 is connected with the other end of the indicator light D4, the other end of the resistor R14 is connected with the other end of the indicator light D5, the other end of the resistor R15 is connected with the other end of the indicator light D6, the other end of the resistor R16 is connected with the other end of the indicator light D7, the other end of the resistor R17 is connected with the other end of the indicator light D8, and the other end of the resistor R18 is connected with the other end of the indicator light D9.

Preferably, the power supply and battery management circuit comprises: a processing chip U5 and a voltage conversion chip U6, wherein the/CHRG terminal of the processing chip U5 is connected to the Chgstatus terminal of the control chip U8, the VCC terminal of the processing chip U5 is connected to one terminal of a capacitor C29, one terminal of a capacitor C28, the cathode of a diode D2 and the source of a FET U4, the other terminal of the capacitor C28 is connected to the other terminal of a capacitor C29 and then grounded, the anode of the diode D2 is connected to an external +12V power input terminal through a charging interface, the GATE of the FET U4 is connected to the GATE terminal of the processing chip U5, the drain of the FET U4 is connected to one terminal of an inductor L5 and the cathode of a diode D1, the anode of a diode D1 is grounded, the other terminal of the inductor L5 is connected to one terminal of a resistor R2, one terminal of a resistor R3, one terminal of a resistor R5 and the SENSE terminal of the processing chip U5, and the other terminal of the resistor R8258 is connected to the other terminal of the resistor R3, The other end of the resistor R5, one end of the capacitor C31, one end of the capacitor C32, the BAT end of the processing chip U5 and the input end of the battery BAT are connected, the other end of the capacitor C32 is respectively connected with the other end of the capacitor C31, the other end of the capacitor C30, the GND end of the processing chip U5 and the NTC end of the processing chip U5, and the other end of the capacitor C30 is connected with the COMP end of the processing chip U5 after being connected with the resistor R4 in series;

the output end of the battery BAT is connected with one end of a capacitor C33, the VIN end of a voltage conversion chip U6, the EN end of a voltage conversion chip U6 and one end of a capacitor C35 respectively, the other end of the capacitor C33 and the other end of a capacitor C35 are both grounded, the GND end of the voltage conversion chip U6 is grounded, the SW end of the voltage conversion chip U6 is connected with an inductor L6 in series and then is connected with one end of a resistor R7, one end of the capacitor C34, one end of a capacitor C37, one end of the capacitor C36 and one end of a resistor R6, the other end of the resistor R7 is connected with one end of a resistor R8, the other end of a capacitor C37 and the FB end of the voltage conversion chip U6 respectively, the other end of the resistor R8 is connected with the other end of a capacitor C37 and the other end of a capacitor C36 and then is grounded, and the other end of the resistor R6 is.

Preferably, the communication circuit includes: the system comprises a 2.4G communication and Bluetooth circuit and a built-in antenna, wherein the built-in antenna is in communication connection with the MCU control module through the 2.4G communication and Bluetooth circuit.

Preferably, the communication circuit includes: the IOT communication antenna is in communication connection with the MCU control module through the IOT communication circuit.

Preferably, the 2.4G communication and bluetooth circuit includes: an XL1 end of the wireless chip U10 is connected to one end of a capacitor C1 and one end of a crystal oscillator X1, respectively, the other end of the capacitor C1 is grounded, the other end of the crystal oscillator X1 is connected to one end of a capacitor C2 and an XL2 end of the wireless chip U10, respectively, a TXRX end of the wireless chip U10 is connected to a pin 9 of a plug N2, an IRQ end of the wireless chip U10 is connected to a pin 8 of a plug N2, a PACE end of the wireless chip U10 is connected to a pin 7 of the plug N2, a CSN end of the wireless chip U2 is connected to a pin 6 of the plug N2, a MOSI end of the wireless chip U2 is connected to a pin 5 of the plug N2, a JCE end of the wireless chip U2 is connected to a pin 3 of the plug N2, a MISO end of the wireless chip U2 is connected to a pin 2 of the plug N2, a pin 4G of the plug U2 is connected to a bluetooth chip 2, and a communication control pin xrx 2 is connected to the plug N2, a pin 8 of the plug N2 is connected with an IRQ end of a control chip U8, a pin 7 of the plug N2 is connected with a JPACE end of the control chip U8, a pin 6 of the plug N2 is connected with a JCSN end of the control chip U8, a pin 5 of the plug N2 is connected with a JMOSI end of the control chip U8, a pin 3 of the plug N2 is connected with a JCE end of the control chip U8, a pin 1 of the plug N2 is connected with a VCC power output end of a power supply and battery management circuit, and a pin 10 of the plug N2 is grounded;

the VCC end of the wireless chip U10 is connected with the VCC power output end of a power supply and battery management circuit, the GND end of the wireless chip U10 is grounded, the ANT end of the wireless chip U10 is connected with one end of a capacitor C5 and one end of an inductor L1 respectively, the other end of an inductor L1 is connected with one end of a capacitor C3, one end of a capacitor C4 and a pin 2 of a connector N1 respectively, the other end of a capacitor C5, the other end of a capacitor C3, the other end of a capacitor C4, a pin 1 of a plug N1 and a pin 3 of a plug N1 are all grounded, and the 2.4G communication and Bluetooth circuit is electrically connected with a built-in antenna through a plug N1.

Preferably, the IOT communication circuit includes: a VCC end of the SIM card is connected to a pin 1 of the TVS diode, one end of a capacitor C51, one end of a capacitor C52, one end of a resistor R54, and a power end SIM _ VDD end of the SIM card, a RST end of the SIM card is connected to a pin 2 of the TVS diode, one end of a capacitor C53, and one end of a resistor R51, a CLK end of the SIM card is connected to a pin 3 of the TVS diode, one end of a capacitor C54, and one end of a resistor R52, a GND end of the SIM card is connected to the other end of the capacitor C51 and the ground end SIM _ GND end of the SIM card, an IO end of the SIM card is connected to a pin 5 of the TVS diode, one end of the capacitor C55, and one end of a resistor R53, the other end of the resistor R51 is connected to a SIM _ GND end of the control chip U8, the other end of the resistor R52 is connected to a SIM _ GND end of the control chip U8, and the other end of the resistor R54 is connected to the RST _ CLK end of the control chip, The SIM _ DATA end of the control chip U8 is connected, and the other end of the capacitor C52, the other end of the capacitor C53, the other end of the capacitor C54 and the other end of the capacitor C55 are all grounded;

the TXD end of the IOT module U41 is connected with the RXD end of the control chip U8, the RXD end of the IOT module U41 is connected with the TXD end of the control chip U8, the GND end of the IOT module U41 is connected with the GND end of the control chip U8, the RF _ AN end of the IOT module U41 is connected with one end of a resistor OR and one end of a capacitor NM1, the other end of the resistor OR is connected with one end of a capacitor NM2 and AN IOT communication antenna, and the other end of the capacitor NM1 and the other end of the capacitor NM2 are both grounded.

Compared with the prior art, the utility model following beneficial effect has:

the utility model adopts a non-contact mode, tests electricity through the method of testing the electricity small window or the small hole of the high-voltage switch cabinet, when in use, only the electric field induction antenna is needed to be put into the electricity small window or the small hole of the high-voltage switch cabinet, and only the test is needed to be carried out on the electricity small window or the infrared observation window without opening the door of the high-voltage switch cabinet, thus having no risk in operation; and single one-hand just can test, need not bulky equipment, and the preparation time is short, and test time only needs tens of seconds to accomplish the detection of an equipment, whole testing process, and is simple and convenient, compares with the tradition handcart mode of testing electricity, has shortened and has tested the electric operating time, has improved and has tested electric efficiency, has high practicality.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings.

FIG. 1 is a schematic view of the structure of the present invention

FIG. 2 is a circuit diagram of the present invention;

fig. 3 is a schematic circuit diagram of a control chip U8 in the MCU control module of the present invention;

FIG. 4 is a schematic circuit diagram of a voltage stabilizing circuit and an external storage circuit in the MCU control module of the present invention;

fig. 5 is a schematic circuit diagram of the middle electric field detection circuit of the present invention;

FIG. 6 is a schematic circuit diagram of the key circuit of the present invention;

FIG. 7 is a schematic circuit diagram of the circuit of the indicator light of the present invention;

FIG. 8 is a schematic circuit diagram of the voice circuit of the present invention;

fig. 9 is a schematic circuit diagram of a power supply and battery management circuit according to the present invention;

fig. 10 is a schematic circuit diagram of a 2.4G communication and bluetooth circuit according to the present invention;

fig. 11 is a schematic view of the communication between the 2.4G communication and bluetooth circuit and the external device of the present invention;

fig. 12 is a schematic circuit diagram of the IOT communication circuit of the present invention;

fig. 13 is a schematic diagram of communication between the IOT communication circuit and the external device according to the present invention;

in the figure: the device comprises a shell 1, an electric field induction antenna 11, a charging interface 12, a key panel 13, an indicator lamp 14 and a loudspeaker 15, wherein the shell is a shell body;

the controller comprises an MCU control module 22, an electric field detection circuit 23, a communication circuit 24, a power supply and battery management circuit 25, a key circuit 26, an indicator light circuit 27 and a voice circuit 28.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention; based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

Fig. 1 is the utility model discloses a schematic structure diagram, fig. 2 are the utility model discloses a circuit connection picture, as shown in fig. 1, fig. 2, a non-contact intelligent electroscope for high voltage electric power equipment, including casing 1, be provided with on the casing 1: the electric field induction antenna 11, the charging interface 12, the key panel 13, the indicator light 14 and the loudspeaker 15; a circuit board is arranged in the shell 1; the circuit board is provided with an MCU control module 22, an electric field detection circuit 23, a communication circuit 24, a power supply and battery management circuit 25, a key circuit 26, an indicator light circuit 27 and a voice circuit 28; electric field induction antenna 11 passes through electric field detection circuit 23 and MCU control module 22's input end electricity and links to each other, communication circuit 24 is connected with MCU control module 22 communication, interface 12 that charges is connected with MCU control module 22's input electricity through power and battery management circuit 25, keypad 13 passes through keypad circuit 26 and is connected with MCU control module 22's input electricity, pilot lamp 14 is connected with MCU control module 22's output electricity through pilot lamp circuit 27, speaker 15 is connected with MCU control module 22's output electricity through voice circuit 28.

Fig. 3 is a schematic circuit diagram of a control chip U8 in the MCU control module of the present invention, fig. 4 is a schematic circuit diagram of a voltage stabilizing circuit and an external storage chip in the MCU control module of the present invention, fig. 5 is a schematic circuit diagram of a middle electric field detection circuit of the present invention, fig. 6 is a schematic circuit diagram of a middle key circuit of the present invention, fig. 7 is a schematic circuit diagram of a middle indicator circuit of the present invention, and fig. 8 is a schematic circuit diagram of a middle voice circuit of the present invention; as shown in fig. 3 to 8, the MCU control module 22 includes: a control chip U8, the electric field detection circuit 23 includes an electric field sensor U7, the voice circuit 28 includes: a voice processing chip U3 and a power amplifier chip U2;

the TX end of the electric field sensor U7 is electrically connected with the electric field induction antenna 11, the VCC end of the electric field sensor U7 is connected with the VCC power output end of the power supply and battery management circuit 25, the SCL end of the electric field sensor U7 is connected with the SCL end of the control chip U8, and the SDA end of the electric field sensor U7 is connected with the SDA end of the control chip U8;

the BUSY end of the voice processing chip U3 is connected with the BUSY end of the control chip U8, the RST end of the voice processing chip U3 is connected with the RST end of the control chip U8, the DATA end of the voice processing chip U3 is connected with the DATA end of the control chip U8, the CLK end of the voice processing chip U3 is connected with the CLK end of the control chip U8, the P end of the voice processing chip U3 is connected with the INP end of the power amplification chip U2, the N end of the voice processing chip U3 is connected with the INN end of the power amplification chip U2, the CTRL end of the power amplification chip U2 is connected with the VCC power output end of the power supply and battery management circuit 25 after being connected with a resistor R1 in series, the CTRL end of the power amplification chip U2 is connected with the CTRL end of the control chip U8, the Byp end of the power amplification chip U2 is connected with a capacitor C26 in series and then grounded, and the VOP end of the power amplification chip U2 is connected with a power induction terminal 1 and a plug pin 599 and, Pin 1 of a plug N5 and pin 3 of a plug N5 are connected, the other end of the capacitor C25 is grounded, the GND end of the power amplifier chip U2 is grounded, the VCC end of the power amplifier chip U2 is connected with the VCC power supply output end of the power supply and battery management circuit 25, the VON end of the power amplifier chip U2 is connected in series with an inductor FB2 and then connected with one end of the capacitor C27, pin 2 of the plug N4, pin 4 of the plug N4, pin 2 of the plug N5 and pin 4 of the plug N5, the other end of the capacitor C27 is grounded, pin 5 of the plug N4 is connected with pin 6 of the plug N4 and then grounded, and pin 5 of the plug N5 is connected with pin 6 of the plug N5 and then grounded; the loudspeaker 15 comprises a first loudspeaker and a second loudspeaker, the voice circuit 28 is electrically connected with the first loudspeaker through a plug N4, and the voice circuit 28 is electrically connected with the second loudspeaker through a plug N5; specifically, the BUSY end of the voice processing chip U3 is a status port, the RST end of the voice processing chip U3 is a reset end, the DATA end of the voice processing chip U3 is a DATA line, the CLK end of the voice processing chip U3 is a synchronous clock line, and the BUSY end, the RST end, the DATA end, and the CLK end are all electrically connected to the control chip U8 and receive an instruction from the control chip U8; further, the power amplifier chip U2 is used for driving the speaker 15, and the P, N is a voice input signal.

The key circuit 26 is a key plug N3, a pin 1 of the key plug N3 is connected in series with a resistor R19 and then connected with one end of the resistor R20, one end of the resistor R21, one end of the resistor R22, one end of the resistor R23 and a VCC power output end of the power and battery management circuit 25, the other end of the resistor R20 is connected with a pin 2 of the key plug N3, the other end of the resistor R21 is connected with a pin 3 of the key plug N3, the other end of the resistor R22 is connected with a pin 4 of the key plug N3, the other end of the resistor R23 is connected with a pin 5 of the key plug N3, and the key circuit 26 is electrically connected with a button arranged on the key panel 13 through a key plug N3;

the indicator light circuit 27 includes: an indicator lamp D3, an indicator lamp D4, an indicator lamp D5, an indicator lamp D6, an indicator lamp D7, an indicator lamp D8 and an indicator lamp D9, wherein one end of the indicator lamp D3 is connected to an LED1 end of a control chip U8, one end of the indicator lamp D4 is connected to an LED2 end of the control chip U8, one end of the indicator lamp D5 is connected to an LED3 end of the control chip U8, one end of the indicator lamp D6 is connected to an LED4 end of the control chip U8, one end of the indicator lamp D7 is connected to an LED5 end of the control chip U8, one end of the indicator lamp D8 is connected to an LED6 end of the control chip U8, one end of the indicator lamp D9 is connected to an LED7 end of the control chip U8, the other end of the indicator lamp D7 is connected to one end of a resistor R7, one end of a VCC power supply of the resistor R7, one end of the power supply of the resistor R7 and the battery management circuit 7, the other end of the resistor R13 is connected with the other end of the indicator light D4, the other end of the resistor R14 is connected with the other end of the indicator light D5, the other end of the resistor R15 is connected with the other end of the indicator light D6, the other end of the resistor R16 is connected with the other end of the indicator light D7, the other end of the resistor R17 is connected with the other end of the indicator light D8, and the other end of the resistor R18 is connected with the other end of the indicator light D9; specifically, control chip U8 is the utility model discloses a core adopts 32 bit ARM MCU, has the characteristic of high-speed low-power consumption, and it accomplishes the control to all modules.

As shown in fig. 4, in the present invention, the MCU control module 22 includes: the voltage stabilizing circuit comprises a chip U9, and the external storage circuit comprises a chip U11;

the VIN end of the chip U9 is connected with one end of a capacitor C40, the input end of a battery BAT and one end of a capacitor C42, the other end of the capacitor C40, the other end of the capacitor C42 and the GND end of the chip U9 are all grounded, the SW end of the chip U9 is connected with an inductor L7 in series and then is connected with one end of a resistor R10, one end of a capacitor C41, one end of a capacitor C44, one end of a capacitor C43 and one end of a resistor R9, the other end of the resistor R10 is respectively connected with one end of a resistor R1 and the FB end of the chip U9, the other end of the resistor R1 is connected with the other end of the capacitor C44 and the other end of the capacitor C43 and then is grounded, and the other end of the resistor R9 is connected with a power supply and the VCC; of said chip U11

The terminal is connected with the SPIO _ CS terminal of the control chip U8, the SCLK terminal of the chip U11 is connected with the SPIO _ SCLK terminal of the control chip U8, the SIO _0/SI terminal of the chip U11 is connected with the SPIO _ MOSI0 terminal of the control chip U8, the SIO _1/SO terminal of the chip U11 is connected with the SPIO _ MISO0 terminal of the control chip U8, and the SIO _ 2/pole of the chip U11

The terminal is connected with the SPIO _ MISO1 terminal of the control chip U8, and the SIO _ 2-

The terminal is connected with the SPIO _ SPIO _ MISOI1 terminal of the control chip U8, the VCC terminal of the chip U11 is connected with the VCC power output terminal of the power supply and battery management circuit 25, and the GND terminal of the chip U11 is grounded.

Fig. 9 is a schematic circuit diagram of the middle power supply and battery management circuit of the present invention, as shown in fig. 9, the power supply and battery management circuit 25 includes: a processing chip U5 and a voltage conversion chip U6, wherein the/CHRG terminal of the processing chip U5 is connected to the Chgstatus terminal of the control chip U8, the VCC terminal of the processing chip U5 is connected to one terminal of a capacitor C29, one terminal of a capacitor C28, the cathode of a diode D2 and the source of a FET U4, the other terminal of the capacitor C28 is connected to the other terminal of a capacitor C29 and then grounded, the anode of the diode D2 is connected to the external +12V power input terminal through a charging interface 12, the GATE of the FET U4 is connected to the GATE terminal of the processing chip U5, the drain of the FET U4 is connected to one terminal of an inductor L5 and the cathode of a diode D1, the anode of a diode D1 is grounded, the other terminal of the inductor L5 is connected to one terminal of a resistor R2, one terminal of a resistor R3, one terminal of a resistor R5 and the SENSE terminal of the processing chip U5, and the other terminal of the resistor R8258 is connected to the other terminal of the resistor R36, The other end of the resistor R5, one end of the capacitor C31, one end of the capacitor C32, the BAT end of the processing chip U5 and the input end of the battery BAT are connected, the other end of the capacitor C32 is respectively connected with the other end of the capacitor C31, the other end of the capacitor C30, the GND end of the processing chip U5 and the NTC end of the processing chip U5, and the other end of the capacitor C30 is connected with the COMP end of the processing chip U5 after being connected with the resistor R4 in series; the output end of the battery BAT is connected with one end of a capacitor C33, the VIN end of a voltage conversion chip U6, the EN end of a voltage conversion chip U6 and one end of a capacitor C35 respectively, the other end of the capacitor C33 and the other end of a capacitor C35 are both grounded, the GND end of the voltage conversion chip U6 is grounded, the SW end of the voltage conversion chip U6 is connected with an inductor L6 in series and then is connected with one end of a resistor R7, one end of the capacitor C34, one end of a capacitor C37, one end of the capacitor C36 and one end of a resistor R6, the other end of the resistor R7 is connected with one end of a resistor R8, the other end of a capacitor C37 and the FB end of the voltage conversion chip U6 respectively, the other end of the resistor R8 is connected with the other end of a capacitor C37 and the other end of a capacitor C36 and then is grounded, and the other end of the resistor R6 is connected.

Specifically, the processing chip U5 is a charging processing chip, an external power supply of +12V is converted into a power supply for charging the battery, the control of the battery charging states such as floating charge, constant voltage, constant current and the like is completed by the processing chip U5, the charging is automatically stopped after the charging is completed, wherein ChgStatus is a charging state bit and is connected with the control chip U8 to represent the current state of the battery; the voltage conversion chip U6 converts the battery voltage into VCC voltage, and provides power supply for other chips such as the control chip U8, and the BAT terminal of the processing chip U5 is connected to the battery.

Fig. 10 is a schematic circuit diagram of the 2.4G communication and bluetooth circuit of the present invention, and fig. 11 is a schematic communication diagram of the 2.4G communication and bluetooth circuit and external devices of the present invention; as shown in fig. 10 and 11, the communication circuit 24 includes: the system comprises a 2.4G communication and Bluetooth circuit and a built-in antenna, wherein the built-in antenna is in communication connection with the MCU control module 22 through the 2.4G communication and Bluetooth circuit; the utility model discloses in, built-in antenna of 2.4G module and bluetooth module sharing, their different places are: 2.4G is a private assistant, the communication distance can reach 800m, and the private assistant is mainly used for communicating with an external wireless alarm terminal, the external wireless alarm terminal can be placed in the range of 800m, when the utility model discloses take place to report to the police, the wireless alarm terminal also reports to the police simultaneously, is used for notifying other staff and supervision personnel; the utility model provides a bluetooth module then mainly is connected with cell-phone APP, the utility model discloses can pass through cell-phone APP program record current alarm time to can shoot the backstage on present picture and pronunciation with APP, play data record function and backstage management and control.

Specifically, the 2.4G communication and bluetooth circuit includes: an XL1 end of the wireless chip U10 is connected to one end of a capacitor C1 and one end of a crystal oscillator X1, respectively, the other end of the capacitor C1 is grounded, the other end of the crystal oscillator X1 is connected to one end of a capacitor C2 and an XL2 end of the wireless chip U10, respectively, a TXRX end of the wireless chip U10 is connected to a pin 9 of a plug N2, an IRQ end of the wireless chip U10 is connected to a pin 8 of a plug N2, a PACE end of the wireless chip U10 is connected to a pin 7 of the plug N2, a CSN end of the wireless chip U2 is connected to a pin 6 of the plug N2, a MOSI end of the wireless chip U2 is connected to a pin 5 of the plug N2, a JCE end of the wireless chip U2 is connected to a pin 3 of the plug N2, a MISO end of the wireless chip U2 is connected to a pin 2 of the plug N2, a pin 4G of the plug U2 is connected to a bluetooth chip 2, and a communication control pin xrx 2 is connected to the plug N2, a pin 8 of the plug N2 is connected with an IRQ end of a control chip U8, a pin 7 of the plug N2 is connected with a JPACE end of the control chip U8, a pin 6 of the plug N2 is connected with a JCSN end of the control chip U8, a pin 5 of the plug N2 is connected with a JMOSI end of the control chip U8, a pin 3 of the plug N2 is connected with a JCE end of the control chip U8, a pin 1 of the plug N2 is connected with a VCC power output end of a power supply and battery management circuit 25, and a pin 10 of the plug N2 is grounded;

the VCC end of the wireless chip U10 is connected with the VCC power output end of the power supply and battery management circuit 25, the GND end of the wireless chip U10 is grounded, the ANT end of the wireless chip U10 is connected with one end of the capacitor C5 and one end of the inductor L1, the other end of the inductor L1 is connected with one end of the capacitor C3, one end of the capacitor C4 and the pin 2 of the connector N1, the other end of the capacitor C5, the other end of the capacitor C3, the other end of the capacitor C4, the pin 1 of the plug N1 and the pin 3 of the plug N1 are grounded, and the 2.4G communication and Bluetooth circuit is electrically connected with the built-in antenna through the plug N1.

In the utility model, the plug N2 is a plug connected with the control chip U8, the JTXRX end of the control chip U8 is a bit for receiving and sending, and 1 represents sending, and 0 represents receiving; the IRQ end of the control chip U8 is 1, when the wireless chip U10 receives the information, the control chip U8 is informed to read the message, and the IRQ end is 0, which indicates no information; the JPACE end of the control chip U8 is opened for opening a PA power amplifier or not, is opened for 1 and is closed for 0, the JCSN end of the control chip U8 is an SPI chip selection signal, the JMOSI end of the control chip U8 is an SPI master output slave input signal, the JMISO end of the control chip U8 is an SPI master input slave output signal, the JCE end of the control chip U8 is a wireless module chip selection signal and works for 1 and enters a standby low power consumption state for 0, the ANT end of the wireless chip U10 is 2.4G signal output, and the plug N1 is connected with a built-in antenna. The 2.4G private protocol and the Bluetooth BLE are wireless module protocol stacks, and are set or called according to the content of the received message through the SPI.

Fig. 12 is a schematic circuit diagram of the IOT communication circuit of the present invention, fig. 13 is a schematic communication diagram of the IOT communication circuit and the external device of the present invention, as shown in fig. 12 and fig. 13, the communication circuit 24 includes: the IOT communication antenna is in communication connection with the MCU control module 22 through the IOT communication circuit.

The utility model discloses in, through IOT communication circuit and IOT communication antenna, can be directly on the network through IOT sends data to backstage management platform, be used for right the utility model discloses an upload, call, supervision etc. of data need insert the SIM card side and can use, use be the GSM network, the GSM antenna is built-in.

Specifically, the IOT communication circuit includes: a VCC end of the SIM card is connected to a pin 1 of the TVS diode, one end of a capacitor C51, one end of a capacitor C52, one end of a resistor R54, and a power end SIM _ VDD end of the SIM card, a RST end of the SIM card is connected to a pin 2 of the TVS diode, one end of a capacitor C53, and one end of a resistor R51, a CLK end of the SIM card is connected to a pin 3 of the TVS diode, one end of a capacitor C54, and one end of a resistor R52, a GND end of the SIM card is connected to the other end of the capacitor C51 and the ground end SIM _ GND end of the SIM card, an IO end of the SIM card is connected to a pin 5 of the TVS diode, one end of the capacitor C55, and one end of a resistor R53, the other end of the resistor R51 is connected to a SIM _ GND end of the control chip U8, the other end of the resistor R52 is connected to a SIM _ GND end of the control chip U8, and the other end of the resistor R54 is connected to the RST _ CLK end of the control chip, The SIM _ DATA end of the control chip U8 is connected, and the other end of the capacitor C52, the other end of the capacitor C53, the other end of the capacitor C54 and the other end of the capacitor C55 are all grounded;

the TXD end of the IOT module U41 is connected with the RXD end of the control chip U8, the RXD end of the IOT module U41 is connected with the TXD end of the control chip U8, the GND end of the IOT module U41 is connected with the GND end of the control chip U8, the RF _ AN end of the IOT module U41 is connected with one end of a resistor OR and one end of a capacitor NM1, the other end of the resistor OR is connected with one end of a capacitor NM2 and AN IOT communication antenna, and the other end of the capacitor NM1 and the other end of the capacitor NM2 are both grounded.

Specifically, SIM _ VDD is the SIM card power supply, SIM _ GND is the SIM card ground, SIM _ RST is the SIM card reset, SIM _ CLK is the clock signal, SIM _ DATA is the serial DATA line, and TVS diode is the protection circuit.

The utility model discloses in, electric field induction antenna 11 responds to electric field signal to send electric field signal intensity value to MCU control module 22 through electric field detection circuit 23 and carry out analysis and judgement, MCU control module 22 judges whether the circuit is electrified back, carries out audible-visual alarm through pilot lamp circuit 27 and voice circuit 28, specifically, keypad 13 sets up corresponding voltage gear through keying circuit 26, the utility model provides a preferred 35kV voltage gear, 10kV voltage gear and 20kV voltage gear of voltage unit.

The utility model adopts a non-contact mode, tests electricity through the method of testing the electricity-testing small window or the small hole of the high-voltage switch cabinet, when in use, the electrified state of the high-voltage switch cabinet can be detected only by putting the electric field induction antenna 11 into the electricity-testing small window or the small hole of the high-voltage switch cabinet, and the operation has no risk because the high-voltage switch cabinet door does not need to be opened and only needs to test the electricity-testing small window or the infrared observation window; and single one-hand just can test, need not bulky equipment, and the preparation time is short, and test time only needs tens of seconds to accomplish the detection of an equipment, whole testing process, and is simple and convenient, compares with the tradition handcart mode of testing electricity, has shortened and has tested the electric operating time, improves and tests electric efficiency, has high practicality.

The utility model discloses a non-contact mode is passed through the high tension switchgear and is tested the method of electricity small window or aperture test and test the electricity, tests the electricity 100% through the on-the-spot practice up to 8 months, does not appear any mistake, reduces operating time 80%, simultaneously because need not open the high tension switchgear door, only need test no risk in electricity small window or infrared observation window, single one-man one-hand just can test simultaneously and need not bulky equipment, test time only need 1 of tens of seconds, the front and back preparation time is also very short; the utility model discloses can guarantee to use more than 7 days under the use built-in battery condition not charging, and be furnished with backup battery, low-power consumption and voice prompt make human-computer interaction simple, can realize the start and use, it also has the test demand of the test demand in reply complicated place and multiple voltage simultaneously, the electricity testing operation under the very suitable high tension switchgear scene.

The utility model discloses also can carry out non-contact electricity testing to 800KV direct current circuit and 1000KV exchanges the extra-high voltage.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.

Claims (7)

1. A non-contact intelligent electroscope for high-voltage power equipment, which comprises a shell (1), and is characterized in that:

the shell (1) is provided with: the device comprises an electric field induction antenna (11), a charging interface (12), a key panel (13), an indicator light (14) and a loudspeaker (15); a circuit board is arranged in the shell (1);

the circuit board is provided with an MCU control module (22), an electric field detection circuit (23), a communication circuit (24), a power supply and battery management circuit (25), a key circuit (26), an indicator light circuit (27) and a voice circuit (28);

electric field induction antenna (11) are connected with the input end electricity of MCU control module (22) through electric field detection circuit (23), communication circuit (24) are connected with MCU control module (22) communication, interface (12) that charges is connected with the input electricity of MCU control module (22) through power and battery management circuit (25), key panel (13) are connected with the input electricity of MCU control module (22) through key circuit (26), pilot lamp (14) are connected with the output electricity of MCU control module (22) through pilot lamp circuit (27), speaker (15) are connected with the output electricity of MCU control module (22) through voice circuit (28).

2. The non-contact intelligent electroscope for high-voltage power equipment according to claim 1, characterized in that: the MCU control module (22) comprises: a control chip U8, the electric field detection circuit (23) includes an electric field sensor U7, the voice circuit (28) includes: a voice processing chip U3 and a power amplifier chip U2;

the TX end of the electric field sensor U7 is electrically connected with an electric field induction antenna (11), the VCC end of the electric field sensor U7 is connected with the VCC power output end of a power supply and battery management circuit (25), the SCL end of the electric field sensor U7 is connected with the SCL end of a control chip U8, and the SDA end of the electric field sensor U7 is connected with the SDA end of a control chip U8;

the BUSY end of the voice processing chip U3 is connected with the BUSY end of the control chip U8, the RST end of the voice processing chip U3 is connected with the RST end of the control chip U8, the DATA end of the voice processing chip U3 is connected with the DATA end of the control chip U8, the CLK end of the voice processing chip U3 is connected with the CLK end of the control chip U8, the P end of the voice processing chip U3 is connected with the INP end of the power amplification chip U2, the N end of the voice processing chip U3 is connected with the INN end of the power amplification chip U2, the CTRL end of the power amplification chip U2 is connected with a resistor R1 in series and then connected with the VCC power output end of a power supply and battery management circuit (25), the CTRL end of the power amplification chip U2 is connected with the CTRL end of the control chip U8, the Bass end of the chip 2 is connected with a capacitor C26 in series and then connected with the capacitor C461, and the plug 581 of the power amplification pin 581, the plug 23 and the plug 24C 23 respectively after the VOP 5 FB 5, A pin 3 of a plug N4, a pin 1 of a plug N5 and a pin 3 of a plug N5 are connected, the other end of the capacitor C25 is grounded, a GND end of the power amplifier chip U2 is grounded, a VCC end of the power amplifier chip U2 is connected with a VCC power output end of a power supply and battery management circuit (25), a VON end of the power amplifier chip U2 is connected with an inductor FB2 in series and then is connected with one end of the capacitor C27, a pin 2 of the plug N4, a pin 4 of the plug N4, a pin 2 of the plug N5 and a pin 4 of the plug N5 respectively, the other end of the capacitor C27 is grounded, a pin 5 of the plug N4 is connected with a pin 6 of the plug N4 and then is grounded, and a pin 5 of the plug N5 is connected with a pin 6 of the plug N5 and then is grounded; the loudspeaker (15) comprises a first loudspeaker and a second loudspeaker, the voice circuit (28) is electrically connected with the first loudspeaker through a plug N4, and the voice circuit (28) is electrically connected with the second loudspeaker through a plug N5;

the key circuit (26) is a key plug N3, a pin 1 of the key plug N3 is connected with a resistor R19 in series and then is connected with one end of a resistor R20, one end of a resistor R21, one end of a resistor R22, one end of a resistor R23 and a VCC power output end of a power and battery management circuit (25), the other end of the resistor R20 is connected with a pin 2 of the key plug N3, the other end of the resistor R21 is connected with a pin 3 of the key plug N3, the other end of the resistor R22 is connected with a pin 4 of the key plug N3, the other end of the resistor R23 is connected with a pin 5 of the key plug N3, and the key circuit (26) is electrically connected with a button arranged on a key panel (13) through the key plug N3;

the indicator light circuit (27) includes: an indicator lamp D3, an indicator lamp D4, an indicator lamp D5, an indicator lamp D6, an indicator lamp D7, an indicator lamp D8 and an indicator lamp D9, wherein one end of the indicator lamp D3 is connected to the end of the LED1 of the control chip U8, one end of the indicator lamp D4 is connected to the end of the LED2 of the control chip U8, one end of the indicator lamp D5 is connected to the end of the LED3 of the control chip U8, one end of the indicator lamp D6 is connected to the end of the LED4 of the control chip U8, one end of the indicator lamp D7 is connected to the end of the LED5 of the control chip U8, one end of the indicator lamp D8 is connected to the end of the LED6 of the control chip U8, one end of the indicator lamp D9 is connected to the end of the LED7 of the control chip U8, and the other end of the indicator lamp D7 is connected to the end of the resistor R7, the power supply of the resistor R7, the power supply (VCC) and the output end of the resistor R7, the power supply circuit (7), the other end of the resistor R13 is connected with the other end of the indicator light D4, the other end of the resistor R14 is connected with the other end of the indicator light D5, the other end of the resistor R15 is connected with the other end of the indicator light D6, the other end of the resistor R16 is connected with the other end of the indicator light D7, the other end of the resistor R17 is connected with the other end of the indicator light D8, and the other end of the resistor R18 is connected with the other end of the indicator light D9.

3. The non-contact intelligent electroscope for high-voltage power equipment according to claim 2, characterized in that: the power and battery management circuit (25) comprises: a processing chip U5 and a voltage conversion chip U6, wherein the/CHRG terminal of the processing chip U5 is connected to the Chgstatus terminal of the control chip U8, the VCC terminal of the processing chip U5 is connected to one terminal of a capacitor C29, one terminal of a capacitor C28, the cathode of a diode D2 and the source of a FET U4, the other terminal of the capacitor C28 is connected to the other terminal of a capacitor C29 and then grounded, the anode of the diode D2 is connected to the external +12V power input terminal through a charging interface (12), the GATE of the FET U4 is connected to the GATE terminal of the processing chip U5, the drain of the FET U4 is connected to one terminal of an inductor L5 and the cathode of a diode D1, the anode of a diode D1 is grounded, the other terminal of the inductor L5 is connected to one terminal of a resistor R2, one terminal of a resistor R3, one terminal of a resistor R5, the SEND 6867 terminal of the processing chip U5, and the other terminal of the resistor R2 is connected to the other terminal of the resistor R3, The other end of the resistor R5, one end of the capacitor C31, one end of the capacitor C32, the BAT end of the processing chip U5 and the input end of the battery BAT are connected, the other end of the capacitor C32 is respectively connected with the other end of the capacitor C31, the other end of the capacitor C30, the GND end of the processing chip U5 and the NTC end of the processing chip U5, and the other end of the capacitor C30 is connected with the COMP end of the processing chip U5 after being connected with the resistor R4 in series;

the output end of the battery BAT is connected with one end of a capacitor C33, the VIN end of a voltage conversion chip U6, the EN end of a voltage conversion chip U6 and one end of a capacitor C35 respectively, the other end of the capacitor C33 and the other end of a capacitor C35 are both grounded, the GND end of the voltage conversion chip U6 is grounded, the SW end of the voltage conversion chip U6 is connected with an inductor L6 in series and then is connected with one end of a resistor R7, one end of the capacitor C34, one end of a capacitor C37, one end of a capacitor C36 and one end of a resistor R6, the other end of the resistor R7 is connected with one end of a resistor R8, the other end of a capacitor C37 and the FB end of the voltage conversion chip U6 respectively, the other end of the resistor R8 is connected with the other end of a capacitor C37 and the other end of a capacitor C36 and then is grounded, and the other end of the resistor R6.

4. The non-contact intelligent electroscope for high-voltage power equipment according to claim 2, characterized in that: the communication circuit (24) comprises: the device comprises a 2.4G communication and Bluetooth circuit and an internal antenna, wherein the internal antenna is in communication connection with the MCU control module (22) through the 2.4G communication and Bluetooth circuit.

5. The non-contact intelligent electroscope for high-voltage power equipment according to claim 2, characterized in that: the communication circuit (24) comprises: the IOT communication antenna is in communication connection with the MCU control module (22) through the IOT communication circuit.

6. The non-contact intelligent electroscope for high-voltage power equipment according to claim 4, characterized in that: 2.4G communication and bluetooth circuit includes: an XL1 end of the wireless chip U10 is connected to one end of a capacitor C1 and one end of a crystal oscillator X1, respectively, the other end of the capacitor C1 is grounded, the other end of the crystal oscillator X1 is connected to one end of a capacitor C2 and an XL2 end of the wireless chip U10, respectively, a TXRX end of the wireless chip U10 is connected to a pin 9 of a plug N2, an IRQ end of the wireless chip U10 is connected to a pin 8 of a plug N2, a PACE end of the wireless chip U10 is connected to a pin 7 of the plug N2, a CSN end of the wireless chip U2 is connected to a pin 6 of the plug N2, a MOSI end of the wireless chip U2 is connected to a pin 5 of the plug N2, a JCE end of the wireless chip U2 is connected to a pin 3 of the plug N2, a MISO end of the wireless chip U2 is connected to a pin 2 of the plug N2, a pin 4G of the plug U2 is connected to a bluetooth chip 2, and a communication control pin xrx 2 is connected to the plug N2, a pin 8 of the plug N2 is connected with an IRQ end of a control chip U8, a pin 7 of the plug N2 is connected with a JPACE end of the control chip U8, a pin 6 of the plug N2 is connected with a JCSN end of the control chip U8, a pin 5 of the plug N2 is connected with a JMOSI end of the control chip U8, a pin 3 of the plug N2 is connected with a JCE end of the control chip U8, a pin 1 of the plug N2 is connected with a VCC power output end of a power supply and battery management circuit (25), and a pin 10 of the plug N2 is grounded;

the VCC end of the wireless chip U10 is connected with the VCC power output end of a power supply and battery management circuit (25), the GND end of the wireless chip U10 is grounded, the ANT end of the wireless chip U10 is connected with one end of a capacitor C5 and one end of an inductor L1 respectively, the other end of an inductor L1 is connected with one end of a capacitor C3, one end of a capacitor C4 and a pin 2 of a connector N1 respectively, the other end of a capacitor C5, the other end of a capacitor C3, the other end of a capacitor C4, a pin 1 of a plug N1 and a pin 3 of a plug N1 are all grounded, and a 2.4G communication and Bluetooth circuit is electrically connected with a built-in antenna through a plug N1.

7. The non-contact intelligent electroscope for high-voltage power equipment according to claim 5, characterized in that: the IOT communication circuit includes: a VCC end of the SIM card is connected to a pin 1 of the TVS diode, one end of a capacitor C51, one end of a capacitor C52, one end of a resistor R54, and a power end SIM _ VDD end of the SIM card, a RST end of the SIM card is connected to a pin 2 of the TVS diode, one end of a capacitor C53, and one end of a resistor R51, a CLK end of the SIM card is connected to a pin 3 of the TVS diode, one end of a capacitor C54, and one end of a resistor R52, a GND end of the SIM card is connected to the other end of the capacitor C51 and the ground end SIM _ GND end of the SIM card, an IO end of the SIM card is connected to a pin 5 of the TVS diode, one end of the capacitor C55, and one end of a resistor R53, the other end of the resistor R51 is connected to a SIM _ GND end of the control chip U8, the other end of the resistor R52 is connected to a SIM _ GND end of the control chip U8, and the other end of the resistor R54 is connected to the RST _ CLK end of the control chip, The SIM _ DATA end of the control chip U8 is connected, and the other end of the capacitor C52, the other end of the capacitor C53, the other end of the capacitor C54 and the other end of the capacitor C55 are all grounded;

the TXD end of the IOT module U41 is connected with the RXD end of the control chip U8, the RXD end of the IOT module U41 is connected with the TXD end of the control chip U8, the GND end of the IOT module U41 is connected with the GND end of the control chip U8, the RF _ AN end of the IOT module U41 is connected with one end of a resistor OR and one end of a capacitor NM1, the other end of the resistor OR is connected with one end of a capacitor NM2 and AN IOT communication antenna, and the other end of the capacitor NM1 and the other end of the capacitor NM2 are both grounded.

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