Indicating device of grounding control electrical cabinet

Abstract

The utility model discloses an indicating device of a grounding control electrical cabinet. The indicating device comprises an MCU, an indicating lamp and a display screen. The MCU is connected to the indicating lamp through the driving and self-checking circuit; the MCU is connected to the display screen; the input end of the hardware filter circuit is used for receiving a switching value signal of the grounding control electrical cabinet, and the output end of the hardware filter circuit is connected to the MCU through the optical coupler isolation circuit. According to the utility model, the hardware filter circuit and the optical coupler isolation circuit are adopted to eliminate interference signals, thereby ensuring that the indicating lamp of the grounding control electrical cabinet can indicate correctly, and avoiding potential safety hazards; and meanwhile, the self-checking and driving circuit is adopted to carry out self-checking on the indicating lamp and upload the damage state of the indicating lamp to the display screen for displaying, so that when the indicating lamp is damaged, a worker can be timely notified to carry out maintenance, safety accidents caused by wrong indication due to the damage of the indicating lamp are avoided, and the safety of the grounding control electrical cabinet is improved.

Description

Technical Field

[0001] This utility model relates to the field of electrical automation control for rail transit, specifically to an indicator device for a grounding control electrical cabinet. Background Technology

[0002] In the field of railway electrical automation, grounding control cabinets are essential equipment. The electrical signals of these cabinets include both digital and analog signals. Digital signals include open / close signals, fault / normal signals, energized / de-energized signals, and manual / automatic signals; analog signals include voltage and resistance signals. Digital signals are indicated by indicator lights within the cabinet, while analog signals are displayed using digital instruments. Multiple indicator lights are needed to display these digital signals, allowing personnel to obtain the operating status of the railway electrical system. Temperature and humidity within the cabinet also need to be controlled to ensure the grounding switches operate in a safe environment. The digital signals within the grounding control cabinet are susceptible to interference from other signals, causing indicator lights to display incorrectly. This prevents personnel from obtaining accurate information about the railway electrical system's status, potentially leading to safety accidents. Furthermore, if indicator lights malfunction, personnel cannot be notified promptly for repair, and incorrect indications can result in accidents and safety hazards.

[0003] To address this issue, an indicating device for a grounding control electrical cabinet is proposed. Utility Model Content

[0004] To address the aforementioned problems, the purpose of this utility model is to provide an indicator device for a grounding control electrical cabinet. This device eliminates interference signals in the input switch signals and performs self-testing on the indicator lights, ensuring they can indicate correctly. This allows staff to obtain accurate information about the railway electrical system status, preventing potential safety hazards. The technical solution adopted is as follows:

[0005] An indicating device for a grounding control electrical cabinet includes an MCU, indicator lights, and a display screen; the MCU is connected to the indicator lights via a drive and self-test circuit; the MCU is connected to the display screen; it also includes a hardware filtering circuit and an optocoupler isolation circuit, the input of the hardware filtering circuit is used to receive the switching signals of the grounding control electrical cabinet, and the output is connected to the MCU via the optocoupler isolation circuit.

[0006] Furthermore, in the hardware filtering circuit: the first end of fuse F1 is the input terminal; the second end of fuse F1 is connected to the cathode of diode D2 and the first end of resistor R1; the second end of resistor R1 is connected to the first end of resistor R4; the first end of resistor R4 is connected to the first end of capacitor C1; the first end of capacitor C1 is connected to the first end of resistor R2; the second end of resistor R2 is connected to the first end of capacitor C2 and the cathode of diode D1; the anode of diode D2, the second end of resistor R4, the second end of capacitor C1, and the second end of capacitor C2 are grounded; and the anode of diode D1 is the output terminal.

[0007] The optocoupler isolation circuit is as follows: the first input terminal of optocoupler U1 is the input terminal, the second input terminal of optocoupler U1 is grounded, the first output terminal of optocoupler U1 is connected to the first terminal of resistor R3, the second terminal of resistor R3 is connected to the power supply, the first terminal of resistor R3 is connected to the first terminal of capacitor C3, the second terminal of capacitor C3 and the second output terminal of optocoupler U1 are grounded, and the first terminal of capacitor C3 is the output terminal.

[0008] Furthermore, in the driving and self-test circuit: the first end of resistor R7 is the input terminal; the second end of resistor R7 is connected to the first end of resistor R31 and the base of transistor Q1; the second end of resistor R31 and the emitter of transistor Q1 are grounded; the collector of transistor Q1 is connected to the first end of resistor R6; the second end of resistor R6 is connected to the cathode of LED D3 and the first end of resistor R5; the anode of LED D3 is connected to the power supply; the second end of resistor R5 is connected to the first end of capacitor C4; the second end of capacitor C4 is grounded; and the first end of capacitor C4 is the output terminal.

[0009] Furthermore, it also includes a temperature and humidity sensor, a heater, and an exhaust fan; the temperature and humidity sensor is connected to the MCU via a first communication circuit; the MCU is also connected to the heater and the exhaust fan in sequence via a Darlington drive circuit and a relay.

[0010] Furthermore, it also includes an external host; the MCU is also connected to the external host in sequence through a digital isolation circuit and a second communication circuit.

[0011] Furthermore, it also includes an operation keyboard; the operation keyboard is connected to the MCU.

[0012] Compared with the prior art, this utility model has the following advantages and beneficial effects:

[0013] 1. This utility model eliminates interference signals in the input switch signals through hardware filtering circuits and optocoupler isolation circuits, ensuring that the indicator lights can indicate correctly, thereby enabling staff to obtain accurate railway electrical system status, improving the safety of the grounding control electrical cabinet and avoiding potential safety hazards.

[0014] 2. This utility model uses a drive and self-test circuit to perform self-testing on the indicator light. The drive and self-test circuit feeds back a damage detection signal to the MCU, which then obtains the indicator light's damage status and displays it on the screen. When an indicator light is damaged, it can promptly notify personnel for repair, avoiding safety accidents caused by erroneous indications due to indicator light malfunction and improving the safety of the grounding control electrical cabinet. Attached Figure Description

[0015] Figure 1 This is a diagram showing the effect after the present invention is installed.

[0016] Figure 2 This is a structural block diagram of the present invention.

[0017] Figure 3 This is a schematic diagram of the hardware filtering circuit and optocoupler isolation circuit of this utility model.

[0018] Figure 4 This is a schematic diagram of the driving and self-testing circuit of this utility model.

[0019] The labels in the diagram are: 1. Display screen; 2. Keyboard; 3. Indicator light. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model, so as to provide a better understanding of the concept of the present utility model, the technical problem solved, the technical features constituting the technical solution and the technical effects brought about.

[0021] like Figure 1 The image shows the effect of an indicator device being installed in a grounding control electrical cabinet.

[0022] like Figure 2 As shown, an indicator device for a grounding control electrical cabinet includes an MCU, indicator lights 3, and a display screen 1. The MCU is connected to the indicator lights 3 via a drive and self-test circuit. The MCU is also connected to the display screen 1. The device further includes a hardware filtering circuit and an optocoupler isolation circuit. The input of the hardware filtering circuit receives the switching signals from the grounding control electrical cabinet, and its output is connected to the MCU via the optocoupler isolation circuit. The display screen 1 can display the damage status of the indicator lights 3 and system parameters. The display screen 1 can display Chinese characters, making the human-machine interaction more user-friendly.

[0023] like Figure 3As shown, the hardware filtering circuit consists of the following: the first end of fuse F1 is the input terminal; the second end of fuse F1 is connected to the cathode of diode D2 and the first end of resistor R1; the second end of resistor R1 is connected to the first end of resistor R4; the first end of resistor R4 is connected to the first end of capacitor C1; the first end of capacitor C1 is connected to the first end of resistor R2; the second end of resistor R2 is connected to the first end of capacitor C2 and the cathode of diode D1; the anode of diode D2, the second end of resistor R4, the second end of capacitor C1, and the second end of capacitor C2 are grounded; and the anode of diode D1 is the output terminal.

[0024] The optocoupler isolation circuit is as follows: the first input terminal of optocoupler U1 is the input terminal, the second input terminal of optocoupler U1 is grounded, the first output terminal of optocoupler U1 is connected to the first terminal of resistor R3, the second terminal of resistor R3 is connected to the power supply, the first terminal of resistor R3 is connected to the first terminal of capacitor C3, the second terminal of capacitor C3 and the second output terminal of optocoupler U1 are grounded, and the first terminal of capacitor C3 is the output terminal.

[0025] Among them, SIGN-CH1 is the input terminal of the hardware filter circuit, F1 is the PTC resettable fuse, D1 is the Zener diode, D2 is the TVS transient suppression diode, R1 is the main current limiting resistor, R2 is the filter resistor, R3 is the signal steady-state resistor, R4 is the interference signal discharge resistor, C1, C2, and C3 are all filter capacitors, U1 is the signal isolation optocoupler, and SIN-CH1 is the output terminal of the optocoupler isolation circuit.

[0026] The principle of the hardware filtering circuit is as follows: (1) When the input signal is overvoltage, diode D2 conducts in reverse to clamp the input voltage, the current increases, and the self-resetting fuse F1 is overcurrent-broken, thus protecting the subsequent circuit from damage; when the input signal contains reverse interference voltage, diode D2 conducts in forward to eliminate the reverse interference voltage, thus protecting optocoupler U1 from being broken down by reverse voltage; (2) When the input signal is low voltage, diode D1 cannot conduct, the current flows through resistor R1 and resistor R4 in sequence, optocoupler U1 does not conduct, thus filtering out abnormal low voltage input signals; (3) When the input signal contains interference surge voltage signals or pulse group signals, The interference energy is first absorbed by diode D2, which absorbs some of the spike interference. The remaining energy is attenuated by resistor R1 and then enters the filter composed of capacitor C1, resistor R2, and capacitor C2. Most of the energy is absorbed by the larger capacitor C1 in the previous stage. The remaining high-frequency glitches are further attenuated by resistor R2 and then absorbed by capacitor C2. After the interference energy is absorbed and stored, it cannot enter the subsequent circuit because the voltage is too low to turn on diode D1. The interference energy stored in capacitors C1 and C2 is released through resistor R4 in the static state to prevent the energy accumulated after absorbing interference signals multiple times from breaking down diode D1 and interfering with the subsequent circuit.

[0027] The input switching signals from the grounding control electrical cabinet are first filtered by a hardware filter circuit to eliminate interference signals, and then electrically isolated by an optocoupler isolation circuit to further eliminate interference signals. The resulting clean switching signals are input to the MCU. The MCU determines whether the switching signal is a continuous signal lasting longer than 200ms to confirm whether the switching signal is valid, and then controls the indicator light 3 to turn on or off, ensuring that indicator light 3 can indicate correctly. This allows staff to obtain accurate information about the railway electrical system status, improves the safety of the grounding control electrical cabinet, and avoids potential safety hazards.

[0028] like Figure 4 As shown, the driving and self-test circuit is as follows: the first end of resistor R7 is the input terminal; the second end of resistor R7 is connected to the first end of resistor R31 and the base of transistor Q1; the second end of resistor R31 and the emitter of transistor Q1 are grounded; the collector of transistor Q1 is connected to the first end of resistor R6; the second end of resistor R6 is connected to the cathode of LED D3 and the first end of resistor R5; the anode of LED D3 is connected to the power supply; the second end of resistor R5 is connected to the first end of capacitor C4; the second end of capacitor C4 is connected to ground; and the first end of capacitor C4 is the output terminal.

[0029] Among them, LED-OUT is the input terminal, R7 is the current limiting resistor, R31 is the steady-state pull-down resistor, Q1 is the NPN driver transistor, R6 is the indicator current limiting resistor, D3 is the light-emitting diode; R5 is the indicator damage detection output resistor, C4 is the filter capacitor, and LED-ADC is the output terminal.

[0030] The principle of the drive and self-test circuit is as follows: When indicator light 3 needs to be lit, the MCU outputs a high-level signal to LED-OUT. After current limiting by resistor R7, the signal is input to the base of transistor Q1, and transistor Q1 enters the saturation conduction state. The power supply (+5V) passes through LED D3, current limiting resistor R6, and transistor Q1 in sequence, thus lighting up LED D3. If indicator light 3 is currently working normally, the voltage drop of LED D3 should be 1.8V, so the voltage of resistor R5 should be 5V-1.8V=3.2V. If indicator light 3 is open-circuited and damaged, the voltage of resistor R5 should be the saturation voltage drop of transistor Q1, 0.3V. If indicator light 3 is short-circuited and damaged, the voltage of resistor R5 should be the power supply voltage of 5V. The signal is input to the MCU through resistor R5. The MCU can collect the voltage of resistor R5 through the ADC circuit and determine whether the voltage of resistor R5 is the normal 3.2V, thereby determining whether indicator light 3 is damaged, and outputting a damage detection signal through LED-ADC.

[0031] The drive and self-test circuit, while driving indicator light 3, outputs a damage detection signal to the MCU. The MCU obtains the damage status of indicator light 3 and displays it on display screen 1. When indicator light 3 is damaged, it can promptly notify personnel for repair, avoiding safety accidents caused by erroneous indications due to indicator light 3 malfunction, and improving the safety of the grounding control electrical cabinet.

[0032] The temperature and humidity sensor is connected to the MCU via a first communication circuit. The MCU is then connected to the heater and exhaust fan via a Darlington drive circuit and a relay. The temperature and humidity sensor collects real-time temperature and humidity data from the grounding control electrical cabinet and sends it to the MCU via the first communication circuit. The MCU displays the real-time temperature and humidity data and the set temperature and humidity range on display screen 1. After judgment and processing, the MCU controls the heater and exhaust fan via the Darlington drive circuit and relay respectively. When the MCU detects that the temperature is below the lower limit, it controls the heater to start heating; when the MCU detects that the temperature is above the lower limit, it controls the heater to stop; when the MCU detects that the humidity is above the upper limit, it controls the exhaust fan to start dehumidifying; when the MCU detects that the humidity is below the upper limit, it controls the exhaust fan to stop. If the temperature and humidity sensor malfunctions, the heater and exhaust fan will not start; if the heater and exhaust fan are already running, they will be forcibly shut down. This achieves the control of the temperature and humidity of the cabinet within the set range, ensuring that the grounding switch of the grounding control electrical cabinet can operate in a safe environment and improving the safety of the grounding control electrical cabinet.

[0033] The external host communicates with the MCU sequentially through the digital isolation circuit and the second communication circuit. It can acquire and display data information such as the operating status and damage status of the indicator light 3 and the operating status of the equipment. At the same time, it can also transmit the information to be displayed to the MCU and display it through the display screen 1 connected to the MCU.

[0034] The operation keyboard 2 is connected to the MCU and is used to modify the set temperature and humidity range (the upper and lower limits of the temperature and humidity range) and system parameters (such as the external communication baud rate), making the human-machine interaction of the grounding control electrical cabinet more convenient.

[0035] The human body sensor is installed outside the door of the grounding control cabinet and connected to the MCU. When a worker approaches, the MCU detects the signal from the human body sensor and immediately lights up display screen 1; if there is no operation, display screen 1 is turned off after a delay, thus saving energy and extending the service life of display screen 1.

[0036] In this embodiment, both the first and second communication circuits are TTL to RS-485 circuits, the display screen 1 is an LCD display screen, and the indicator light 3 is an LED light.

Claims

1. An indicating device for a grounding control electrical cabinet, characterized in that: It includes an MCU (1), an indicator light (3), and a display screen; the MCU (1) is connected to the indicator light (3) through a drive and self-test circuit; the MCU (1) is connected to the display screen; it also includes a hardware filter circuit and an optocoupler isolation circuit, the input of the hardware filter circuit is used to receive the switching signal of the grounding control electrical cabinet, and the output is connected to the MCU (1) through the optocoupler isolation circuit.

2. The indicating device for a grounding control electrical cabinet as described in claim 1, characterized in that: The hardware filtering circuit consists of the following: the first end of fuse F1 is the input terminal; the second end of fuse F1 is connected to the cathode of diode D2 and the first end of resistor R1; the second end of resistor R1 is connected to the first end of resistor R4; the first end of resistor R4 is connected to the first end of capacitor C1; the first end of capacitor C1 is connected to the first end of resistor R2; the second end of resistor R2 is connected to the first end of capacitor C2 and the cathode of diode D1; the anode of diode D2, the second end of resistor R4, the second end of capacitor C1, and the second end of capacitor C2 are grounded; and the anode of diode D1 is the output terminal. The optocoupler isolation circuit is as follows: the first input terminal of optocoupler U1 is the input terminal, the second input terminal of optocoupler U1 is grounded, the first output terminal of optocoupler U1 is connected to the first terminal of resistor R3, the second terminal of resistor R3 is connected to the power supply, the first terminal of resistor R3 is connected to the first terminal of capacitor C3, the second terminal of capacitor C3 and the second output terminal of optocoupler U1 are grounded, and the first terminal of capacitor C3 is the output terminal.

3. The indicating device for a grounding control electrical cabinet as described in claim 1, characterized in that: The driving and self-test circuit consists of the following: the first end of resistor R7 is the input terminal; the second end of resistor R7 is connected to the first end of resistor R31 and the base of transistor Q1; the second end of resistor R31 and the emitter of transistor Q1 are grounded; the collector of transistor Q1 is connected to the first end of resistor R6; the second end of resistor R6 is connected to the cathode of LED D3 and the first end of resistor R5; the anode of LED D3 is connected to the power supply; the second end of resistor R5 is connected to the first end of capacitor C4; the second end of capacitor C4 is grounded; and the first end of capacitor C4 is the output terminal.

4. The indicating device for a grounding control electrical cabinet as described in claim 1, characterized in that: It also includes a temperature and humidity sensor, a heater and an exhaust fan; the temperature and humidity sensor is connected to the MCU (1) through the first communication circuit; the MCU (1) is also connected to the heater and the exhaust fan in sequence through the Darlington drive circuit and the relay.

5. The indicating device for a grounding control electrical cabinet as described in claim 1, characterized in that: It also includes an external host; the MCU (1) is also connected to the external host in sequence through a digital isolation circuit and a second communication circuit.

6. The indicating device for a grounding control electrical cabinet as described in claim 1, characterized in that: It also includes an operation keyboard (2); the operation keyboard (2) is connected to the MCU (1).

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