CN207301222U - A kind of electrical equipment protective grounding state monitoring apparatus - Google Patents

Abstract

The utility model discloses a monitoring device for protecting and grounding state of electrical equipment, which relates to the technical field of safety protection of electrical equipment in a power system. The device for protecting the grounding state of electrical equipment includes a chassis, switches or buttons arranged on the chassis, and a power module, a grounding state monitoring control unit and an alarm unit disposed in the chassis, the grounding state monitoring control unit Including the sampling resistor, photoelectric isolation circuit and single-chip monitoring unit connected in sequence; the connection point between the sampling resistor and the input ground terminal of the photoelectric isolation circuit is used as the PE grounding protection monitoring output terminal; when the electrical equipment protection grounding state is monitored, the electrical equipment is grounded The terminal is connected to the common ground of the PE grounding protection monitoring output terminal, and the status of the PE grounding protection monitoring output terminal is continuously monitored in real time through the single-chip microcomputer monitoring unit to realize real-time and continuous monitoring of the grounding status of the electrical equipment.

Description

A protective grounding state monitoring device for electrical equipment

technical field

The utility model belongs to the safety protection technology of electrical equipment in an electric power system, in particular to a monitoring device for the protection grounding state of electrical equipment.

Background technique

During the use of electrical equipment, the metal casing of the equipment needs to be provided with a dedicated protective grounding wire. Especially for the electrical equipment used at the substation site of the power supply bureau, due to the complex test environment on site, large interference, and strong induction current, if the electrical equipment has poor grounding wire contact, broken wire or unconnected wire during use If the situation, the protective grounding loses its proper protective effect on personal safety.

At present, there is still a lack of continuous and effective monitoring means for the status of the protective grounding wire of electrical equipment. Without changing the original structure and functional state of the electrical equipment, the present invention proposes a method and a monitoring device for continuous monitoring of the protective grounding state of the electrical equipment. Real-time monitoring is of great significance to the safe production of the power sector and the personal safety of field test personnel.

Utility model content

Aiming at the deficiencies of the prior art, the utility model provides a monitoring device for protecting and grounding state of electrical equipment.

The utility model solves the above-mentioned technical problems through the following technical solutions: a device for monitoring the grounding state of electrical equipment protection, including a chassis, switches or buttons arranged on the chassis, and a power supply module arranged in the chassis , grounding state monitoring control unit and alarm unit;

The power module includes an AC/DC power module, and a rectifier module, a PWM pulse step-down module, and a voltage-stabilizing output module connected in sequence; the ground state monitoring control unit includes a sampling resistor, a photoelectric isolation circuit, and a single-chip microcomputer monitoring unit connected in sequence ; The output end of the AC/DC power supply module is connected to the monitoring unit of the single-chip microcomputer; the output end of the voltage stabilizing output module is connected to one end of the sampling resistor, and the other end of the sampling resistor is connected to the input grounding end of the photoelectric coupling circuit connected, and lead out as the PE grounding protection monitoring output; the single-chip monitoring unit is connected to the alarm unit.

Further, the switch or key includes a power switch, a test key, and a mute key; one end of the power switch is connected to the input ends of the AC/DC power module and the rectifier module; the other end is connected to an external AC power supply for controlling The working power supply of the device; the test key and the silence key are respectively connected with the single-chip microcomputer monitoring unit, and are respectively used to start monitoring and cancel the alarm sound when the sound and light alarm is issued.

Further, the AC/DC power supply module includes a transistor, a sampling module, a reference voltage module, a comparison module and a light-emitting diode; the sampling module includes a sampling resistor and a temperature-sensitive resistor connected in series; the reference voltage module includes two Resistors R1 and R2 connected in series; the comparison module includes a comparator and an NPN transistor, the output terminal of the comparator is connected to the base of the NPN transistor, the collector of the NPN transistor is connected to the power supply, and the emitter of the NPN transistor is connected to the light emitting diode. Diode connection; the temperature-sensitive resistor is attached to the transistor; the common connection point of the sampling resistor and the temperature-sensitive resistor is connected to the same input end of the comparator; the common connection of the resistor R1 and the resistor R2 The point is connected with the inverting input terminal of the comparator; when the temperature of the transistor is too high, the light-emitting diode sends out a light alarm, so as to remind the operator to take measures to prevent the transistor from burning out.

Further, the photoelectric coupling circuit uses a TLP632 photoelectric coupling chip.

Further, the single-chip microcomputer monitoring unit adopts a single-chip microcomputer chip of the model STM32L151, and performs double logic combination judgment on the isolated input signals at both ends of the sampling resistor through the P0.1 and P0.2 input IO interfaces of the STM32L151 chip to judge the grounding state Is it normal.

Compared with the prior art, the device for protecting the grounding state of electrical equipment provided by the utility model includes a chassis, switches or buttons arranged on the chassis, and a power supply module and a grounding state monitoring control unit arranged in the chassis And an alarm unit, the ground state monitoring control unit includes a sampling resistor connected in sequence, a photoelectric isolation circuit and a single-chip microcomputer monitoring unit; the connection point of the input ground terminal of the sampling resistor and the photoelectric isolation circuit is drawn as the PE grounding protection monitoring output terminal; in the electrical equipment When monitoring the protective grounding state, connect the grounding terminal of the electrical equipment to the PE grounding protection monitoring output terminal, and continuously monitor the status of the PE grounding protection monitoring output terminal in real time through the single-chip microcomputer monitoring unit. When the PE grounding protection monitoring output terminal and the ground wire appear When the contact is poor, the wire is disconnected or not connected, the high level of the PE grounding protection monitoring output terminal is monitored by the single-chip microcomputer monitoring unit, and the control alarm unit sends out an audible and visual alarm to realize real-time and continuous monitoring of the grounding status of electrical equipment and protect field test personnel. personal safety; the monitoring device of the present invention has the advantages of simple structure, reliability, safe use and convenient monitoring.

Description of drawings

In order to illustrate the technical solution of the utility model more clearly, the accompanying drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only an embodiment of the utility model. For Those of ordinary skill in the art can also obtain other drawings based on these drawings without any creative effort.

Fig. 1 is a structural block diagram of an electrical equipment protection grounding state device of the present invention;

Fig. 2 is the wiring diagram of the electrical equipment and the electrical equipment protection grounding state monitoring device of the present invention;

Among them: 1-PE grounding protection monitoring output terminal, 2-grounding terminal, 3-sampling resistance.

Detailed ways

The technical solutions in this implementation model will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of them. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

As shown in Figure 1, a device for monitoring the grounding state of electrical equipment protection provided by the utility model includes a chassis, switches or buttons arranged on the chassis, and a power supply module, a grounding state monitoring control unit and an alarm set in the chassis. unit;

The power supply module includes an AC/DC power supply module, and a rectification module, a PWM pulse step-down module, and a voltage-stabilizing output module connected in sequence; the grounding state monitoring control unit includes a sampling resistor 3, a photoelectric isolation circuit, and a single-chip microcomputer monitoring unit connected in sequence; The output end of the DC power supply module is connected to the single-chip monitoring unit; the output end of the voltage-stabilizing output module is connected to one end of the sampling resistor 3, and the other end of the sampling resistor 3 is connected to the input grounding end of the photoelectric coupling circuit, and leads out as a PE grounding protection monitoring Output terminal 1; the single-chip microcomputer monitoring unit is connected with the alarm unit.

The switch or key includes a power switch, a test key and a mute key; one end of the power switch is respectively connected to the input ends of the AC/DC power supply module and the rectifier module; the other end is connected to an external AC power supply for the working power of the control device; the test key The and mute keys are respectively connected with the single-chip microcomputer monitoring unit, and are respectively used for starting monitoring and canceling the alarm sound when sound and light alarms are issued.

The AC/DC power supply module includes a transistor, a sampling module, a reference voltage module, a comparison module and a light-emitting diode; the sampling module includes a sampling resistor and a temperature-sensitive resistor connected in series; the reference voltage module includes two resistors R1 and R2 connected in series; The module includes a comparator and an NPN transistor, the output of the comparator is connected to the base of the NPN transistor, the collector of the NPN transistor is connected to the power supply, and the emitter of the NPN transistor is connected to the light-emitting diode; the temperature sensitive resistor is attached to the transistor; the sampling The common connection point of the resistor and the temperature-sensitive resistor is connected to the same input terminal of the comparator; the common connection point of the resistor R1 and the resistor R2 is connected to the inverting input terminal of the comparator; when the temperature of the transistor is too high, the light-emitting diode emits light Alarm to remind the operator to take measures to prevent the transistor from burning out.

The photoelectric coupling circuit adopts TLP632 photoelectric coupling chip.

As shown in Figure 2, when monitoring the protective grounding status of electrical equipment, the grounding terminal 2 of the electrical equipment is connected to the common ground of the PE grounding protection monitoring output terminal 1, and the PE grounding protection monitoring output terminal 1 is continuously monitored in real time by the single-chip microcomputer monitoring unit. State: The single-chip microcomputer monitoring unit adopts the single-chip microcomputer chip of the model STM32L151, through the P0.1 and P0.2 input IO interfaces of the STM32L151 chip, the isolated input signal at both ends of the sampling resistor is judged by a double logic combination to judge whether the grounding state is normal. In this embodiment, the resistance value of the sampling resistor 3 is 40 ohms. When the monitoring device enters the monitoring state, the P0.1 port is 1, and the P0.2 port (PE grounding protection monitoring output terminal 1) is monitored; when the PE grounding protection monitoring output terminal 1 and the ground wire have poor contact, disconnection or When not connected, the PE grounding protection monitoring output terminal 1 is high level, P0.2 port is 1, the grounding state is bad, and the monitoring device sends out an audible and visual alarm.

What is disclosed above is only the specific embodiment of the present utility model, but the scope of protection of the present utility model is not limited thereto. Any skilled person familiar with the technical field can easily think of changes or modifications within the technical scope disclosed by the utility model. Variations should be covered within the protection scope of the present utility model.

Claims (5)

1. A protective grounding state monitoring device for electrical equipment, characterized in that: comprising a chassis, switches or buttons arranged on the chassis, and a power module, a grounding state monitoring control unit and an alarm unit arranged in the chassis; The power module includes an AC/DC power module, and a rectifier module, a PWM pulse step-down module, and a voltage-stabilizing output module connected in sequence; the ground state monitoring control unit includes a sampling resistor, a photoelectric isolation circuit, and a single-chip microcomputer monitoring unit connected in sequence ; The output end of the AC/DC power supply module is connected to the monitoring unit of the single-chip microcomputer; the output end of the voltage stabilizing output module is connected to one end of the sampling resistor, and the other end of the sampling resistor is connected to the input grounding end of the photoelectric coupling circuit connected, and lead out as the PE grounding protection monitoring output; the single-chip monitoring unit is connected to the alarm unit. 2. The electrical equipment protection grounding state monitoring device as claimed in claim 1, characterized in that: said switch or key comprises a power switch, a test key and a silencer key; one end of said power switch is connected to the AC/DC power supply module and The input end of the rectifier module is connected; the other end is connected with an external AC power supply, which is used to control the working power of the device; the test key and the silence key are respectively connected with the single-chip microcomputer monitoring unit, and are respectively used for starting monitoring and canceling when an audible and visual alarm is issued. Alarm sound. 3. The electrical equipment protective grounding state monitoring device as claimed in claim 1, wherein: the AC/DC power supply module includes a transistor, a sampling module, a reference voltage module, a comparison module and a light emitting diode; the sampling module includes a mutual A sampling resistor and a temperature-sensitive resistor connected in series; the reference voltage module includes two resistors R1 and R2 connected in series; the comparison module includes a comparator and an NPN transistor, and the output terminal of the comparator is connected to the base of the NPN transistor connected, the collector of the NPN transistor is connected to the power supply, and the emitter of the NPN transistor is connected to the light-emitting diode; the temperature-sensitive resistor is attached to the transistor; the common connection point of the sampling resistor and the temperature-sensitive resistor is compared with the The same input terminal of the comparator is connected; the common connection point of the resistor R1 and the resistor R2 is connected to the inverting input terminal of the comparator. 4. The device for monitoring the protective grounding state of electrical equipment according to claim 1, wherein the photoelectric coupling circuit adopts a TLP632 photoelectric coupling chip. 5. The electrical equipment protection grounding state monitoring device as claimed in claim 1, characterized in that: the single-chip microcomputer monitoring unit adopts a single-chip microcomputer chip with a model number of STM32L151, through two input IO interfaces of P0.1 and P0.2 of the STM32L151 chip Perform dual logic combination judgment on the isolated input signal at both ends of the sampling resistor to judge whether the grounding state is normal.