A kind of FAS cylinder electromagnetic valve drive signal voltage current detection device

Abstract

The utility model discloses a kind of FAS gas cylinder solenoid valve driving signal voltage current detection device, including MCU main control circuit, input voltage detection circuit and current detection circuit;The input voltage detection circuit includes rectifier circuit, polarity conversion circuit and input voltage acquisition circuit;The polarity conversion circuit is used to identify the polarity of input voltage;The input voltage acquisition circuit is used to collect voltage signal after rectification and polarity identification, and the signal collected is transmitted to the MCU main control circuit;The current detection circuit is used to collect the current value of input loop, and the signal collected is transmitted to the MCU main control circuit.The utility model makes that device can automatically adapt the positive and negative polarity of input signal by built-in rectifier circuit and polarity conversion circuit, without manual judgment, simplify operation;In addition, input voltage and current value can be measured simultaneously and synchronously, and through ADC and operational amplifier circuit, the accuracy and reliability of measurement data are guaranteed.

Description

Technical Field

[0001] This utility model belongs to the field of rail transit facility maintenance technology, and in particular relates to a device for detecting the voltage and current of the drive signal of an FAS gas cylinder solenoid valve. Background Technology

[0002] During the annual inspection of FAS (Fire Protection System) professional gas extinguishing systems in rail transit, the proper functioning of the gas cylinder solenoid valve is crucial for the system's effective fire suppression. The solenoid valve is typically driven by 24V DC voltage, with a power output of up to 36W. FAS gas extinguishing systems contain cylinders filled with inert gas. In the event of a fire, the solenoid valve opens, releasing the gas from the cylinder for use in rooms requiring gas extinguishing. If the FAS extinguishing panel itself malfunctions, resulting in insufficient output capacity to drive the solenoid valve, it will cause malfunctions such as the inability to open the gas cylinder, preventing gas extinguishing and potentially leading to serious consequences.

[0003] In the annual inspection of FAS professional gas extinguishing systems, maintenance personnel generally use digital multimeters to measure the no-load voltage of the solenoid valve plug to determine whether the emergency start function is normal. However, in actual operation, before measurement, the operator needs to manually determine the positive and negative terminals of the voltage. If the terminals are reversed, the correct reading may not be obtained or the instrument may be damaged. The process is cumbersome and requires a high level of experience. In addition, traditional multimeters can only perform single voltage or current measurements, making it difficult to monitor the two key parameters of voltage and current simultaneously and synchronously. They also lack data recording, automatic judgment, and alarm functions. Utility Model Content

[0004] To address the shortcomings of existing technologies, the purpose of this utility model is to provide a device for detecting the voltage and current of the drive signal of an FAS gas cylinder solenoid valve, thereby solving the technical problems mentioned in the background art.

[0005] This utility model provides the following technical solution: A device for detecting the voltage and current of the drive signal of an FAS gas cylinder solenoid valve includes an MCU main control circuit, an input voltage detection circuit, and a current detection circuit. The input voltage detection circuit includes a rectifier circuit, a polarity conversion circuit, and an input voltage acquisition circuit. The input terminal of the rectifier circuit is used to connect to the drive signal of the solenoid valve under test and to perform full-wave rectification on the input voltage. The input terminal of the polarity conversion circuit is connected to the input terminal of the rectifier circuit and is used to identify the polarity of the input voltage. Its output terminal is connected to the input voltage acquisition circuit. The input voltage acquisition circuit is used to acquire the voltage signal after rectification and polarity identification, and transmit the acquired signal to the MCU main control circuit. The current detection circuit is connected in series in the output circuit of the rectifier circuit to collect the current value of the input circuit and transmit the collected signal to the MCU main control circuit.

[0006] Preferably, the polarity conversion circuit uses an analog switch, and the channel selection terminal of the analog switch is connected to the MCU main control circuit and controlled by it to switch different voltage divider networks, thereby identifying the positive and negative polarities of the input voltage.

[0007] Preferably, the input voltage acquisition circuit includes a voltage follower and an analog-to-digital converter (ADC); the input terminal of the voltage follower is connected to the output terminal of the polarity conversion circuit to improve the input impedance; the input terminal of the ADC is connected to the output terminal of the voltage follower, and its digital output terminal is connected to the MCU main control circuit.

[0008] Preferably, the current detection circuit uses a current sampling chip, which is connected in series in the positive output circuit of the rectifier circuit. Its output terminal is connected to an analog-to-digital converter (ADC) and then to the MCU main control circuit.

[0009] Preferably, it also includes a human-machine interface and an audible and visual alarm circuit, both of which are connected to the MCU main control circuit and are used to display the measured voltage and current data and to issue an alarm in case of abnormality.

[0010] Preferably, it also includes a USB Type-C interface circuit, which is connected to a lithium battery charging management circuit for charging the lithium battery in the device.

[0011] Compared with the prior art, the present invention has the following beneficial effects: This utility model discloses a voltage and current detection device for the drive signal of an FAS gas cylinder solenoid valve. Through the built-in rectifier circuit and polarity conversion circuit, the device can automatically adapt to the positive and negative polarities of the input signal, eliminating the need for manual judgment and simplifying operation. In addition, it can simultaneously and synchronously measure the input voltage and current values, and through ADC and operational amplifier circuits, it ensures the accuracy and reliability of the measurement data. Attached Figure Description

[0012] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments are briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is the overall circuit block diagram of this utility model.

[0014] Figure 2This is the circuit diagram for the input voltage detection of this utility model.

[0015] Figure 3 This is the battery power-on / off circuit diagram of this utility model.

[0016] Figure 4 This is the boost circuit diagram of this utility model.

[0017] Figure 5 This is a circuit diagram of the TP4056 lithium battery charging circuit of this utility model.

[0018] Figure 6 This is the circuit diagram of the electronic load constant current circuit of this utility model.

[0019] Figure 7 This is the circuit diagram of the LCD screen of this utility model.

[0020] Figure 8 This is the circuit diagram of the USB interface of this utility model.

[0021] Figure 9 This is the main control circuit diagram of this utility model. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0023] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] This utility model provides a device for detecting the voltage and current of the drive signal of an FAS gas cylinder solenoid valve, referenced. Figure 1-9 As shown, it includes an MCU main control circuit, an input voltage detection circuit, and a current detection circuit; The input voltage detection circuit includes a rectifier circuit, a polarity conversion circuit, and an input voltage acquisition circuit; The input terminal of the rectifier circuit is used to connect to the drive signal of the solenoid valve under test, and performs full-wave rectification on the input voltage so that the subsequent circuit is not affected by the input polarity. The input terminal of the polarity conversion circuit is connected to the input terminal of the rectifier circuit to identify the polarity of the input voltage, and its output terminal is connected to the input voltage acquisition circuit. The input voltage acquisition circuit is used to acquire the voltage signal after rectification and polarity identification, and transmit the acquired signal to the MCU main control circuit; The current detection circuit is connected in series in the output circuit of the rectifier circuit to collect the current value of the input circuit and transmit the collected signal to the MCU main control circuit.

[0025] refer to Figure 1 This is the overall circuit block diagram. After the input voltage detection circuit, one path goes through a rectifier circuit and a current detection circuit before connecting to the electronic load constant current circuit. The other path goes through a polarity conversion circuit and a voltage follower signal processing circuit, then is sent to the input voltage acquisition circuit's ADC for conversion before being fed to the MCU main control circuit. The current detection circuit converts the current signal into an analog voltage, which is then converted by the ADC and sent to the MCU main control circuit. The constant current value of the electronic load constant current circuit is controlled and set by the MCU main control circuit. The MCU control output shutdown circuit can reset the constant current value of the electronic load constant current circuit to zero. An NTC resistor is included in the electronic load constant current circuit for temperature acquisition to prevent damage caused by excessively high operating temperatures. Connected to the MCU main control circuit are a USB interface circuit and an LCD screen for charging and human-machine interaction.

[0026] The polarity conversion circuit uses an analog switch. The channel selection terminal of the analog switch is connected to the MCU main control circuit and is controlled by it to switch different voltage divider networks, thereby identifying the positive and negative polarities of the input voltage.

[0027] The input voltage acquisition circuit includes a voltage follower and an analog-to-digital converter (ADC); the input terminal of the voltage follower is connected to the output terminal of the polarity conversion circuit to improve the input impedance; the input terminal of the ADC is connected to the output terminal of the voltage follower, and its digital output terminal is connected to the MCU main control circuit.

[0028] The current detection circuit uses a current sampling chip, which is connected in series in the positive output circuit of the rectifier circuit. Its output terminal is connected to an analog-to-digital converter (ADC) and then to the MCU main control circuit.

[0029] It also includes a human-machine interface and an audible and visual alarm circuit. Both the human-machine interface and the audible and visual alarm circuit are connected to the MCU main control circuit and are used to display the measured voltage and current data and to trigger an alarm in case of abnormalities. The integrated human-machine interface can simultaneously display multiple information such as voltage, current, and polarity, and combined with the audible and visual alarm, makes the test results clear at a glance, supports data recording, facilitates subsequent analysis, and significantly improves the professionalism and efficiency of maintenance work.

[0030] It also includes a USB Type-C interface circuit, which is connected to a lithium battery charging management circuit for charging the lithium battery in the device.

[0031] refer to Figure 2 This is the input voltage detection circuit. U10 is the external input interface. VIN1 and VIN2 are connected to the external input voltage. After rectification by diodes D1, D2, D3, and D4, and filtering by C14, the voltage passes through the high-side current sampling circuit. U2 INA193 performs high-side current sampling, and the current is detected by the conversion by ADS1110. R5, R9, R11, R15, R21, and R22 constitute a positive and negative 36V voltage acquisition circuit. The input voltage is switched and identified by the analog switch BL1551, thereby realizing the acquisition of the external voltage. After passing through the voltage follower circuit composed of the operational amplifier U16 LM321, the voltage is acquired by U4 ADS1110, and the external voltage data is obtained after processing and conversion by the MCU.

[0032] refer to Figure 3 This is the battery power-on / off circuit. The battery power-on / off circuit is used for power-on / off control, using a mechanical button to control the device's power on / off. It uses the MPS003 power-on / off chip, which is packaged in an SOT23-6 package. The MPS003 is small in size, reducing PCB footprint and BOM cost, and has a minimum static power consumption of 0.16uA. VDD is connected to the positive terminal of the lithium battery, and the supply voltage range is 1.8-5.5V, meeting the 2.5-4.2V voltage range of a single lithium battery. The KEY pin is connected to the button; LONG is high or floating for a long press mode, and grounded for a short press mode; OUTL is low by default after power-on, and ETH is high by default. When the KEY button is pressed, OUTL changes from low to high, and ETH changes from high to low. Q2 is a PMOS transistor AO3401A used to control the device's power on / off, and capacitor C6 is used for filtering. R26 and D7 serve as power indicator lights.

[0033] refer to Figure 4This is a boost circuit. VCC is the output voltage of the battery power-on / off circuit. When the battery power-on / off circuit is turned on, VCC is the voltage of a single lithium battery cell, ranging from 2.5V to 4.2V. After processing by the circuit constructed with SX1308, a stable 5V and -5V are output to power the system.

[0034] refer to Figure 5 This is a TP4056 lithium battery charging circuit. It is used to charge a single lithium battery pack. The 5V USB power supply provides power to the chip. D14 and D15 are charging indicator lights. R45 is used to set the charging current. C33 is the output filter capacitor for battery charging.

[0035] refer to Figure 6 This is an electronic load constant current circuit. It is used for numerically controlled constant current, enabling the setting of a numerically controlled electronic constant current for the circuit under test. After applying a load to the circuit under test, its load-carrying capacity is tested, achieving functional verification. The constant current circuit mainly uses a U15 LM321 operational amplifier, Q5 NMOS transistor, Q5 ANMOS transistor, and R64 current sampling alloy resistor. Q3 is an NMOS transistor used for the output shutdown circuit. When a constant current of 0mA is required, Q3 NMOS transistor conducts, pulling the output low and achieving shutdown. DAC_A1 is the constant current setting voltage; controlling this voltage allows the setting of the constant current value.

[0036] refer to Figure 7 This is the LCD screen circuit. A GMT024 LCD screen is used, and Q15, R89, R88, R87, and C39 constitute the backlight driver circuit. The MCU main control chip communicates with the LCD screen via the IIC interface.

[0037] refer to Figure 8 This is a USB interface circuit. It uses a USB Type-C interface for device charging and data exchange.

[0038] refer to Figure 9 The main control circuit uses ST's 32-bit microcontroller STM32F407ZGT6 to perform detection and control operations on the device.

[0039] During operation, the tester only needs to reliably connect the device's input cable to the solenoid valve drive signal terminal, without needing to worry about the positive or negative polarity. After the MCU is powered on, it automatically executes the polarity identification process and clearly displays the current voltage polarity (positive / reverse connection), voltage value, and current value on the LCD screen. If the voltage or current value exceeds the preset normal range (e.g., voltage below 23V, current unable to reach the rated value), the device will activate an audible and visual alarm (such as a buzzer and LED) to provide a warning and record the measurement data in its internal memory.

[0040] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A device for detecting the voltage and current of the drive signal of a FAS gas cylinder solenoid valve, characterized in that, Includes MCU main control circuit, input voltage detection circuit and current detection circuit; The input voltage detection circuit includes a rectifier circuit, a polarity conversion circuit, and an input voltage acquisition circuit. The input terminal of the rectifier circuit is used to connect to the drive signal of the solenoid valve under test and to perform full-wave rectification on the input voltage. The input terminal of the polarity conversion circuit is connected to the input terminal of the rectifier circuit and is used to identify the polarity of the input voltage. Its output terminal is connected to the input voltage acquisition circuit. The input voltage acquisition circuit is used to acquire the voltage signal after rectification and polarity identification, and transmit the acquired signal to the MCU main control circuit. The current detection circuit is connected in series in the output circuit of the rectifier circuit to collect the current value of the input circuit and transmit the collected signal to the MCU main control circuit.

2. The device for detecting the voltage and current of the drive signal of the FAS gas cylinder solenoid valve according to claim 1, characterized in that, The polarity conversion circuit uses an analog switch. The channel selection terminal of the analog switch is connected to the MCU main control circuit and is controlled by it to switch different voltage divider networks, thereby identifying the positive and negative polarities of the input voltage.

3. The device for detecting the voltage and current of the drive signal of the FAS gas cylinder solenoid valve according to claim 1, characterized in that, The input voltage acquisition circuit includes a voltage follower and an analog-to-digital converter (ADC); the input terminal of the voltage follower is connected to the output terminal of the polarity conversion circuit to increase the input impedance; the input terminal of the ADC is connected to the output terminal of the voltage follower, and its digital output terminal is connected to the MCU main control circuit.

4. The FAS gas cylinder solenoid valve drive signal voltage and current detection device according to claim 1, characterized in that, The current detection circuit uses a current sampling chip, which is connected in series in the positive output circuit of the rectifier circuit. Its output terminal is connected to an analog-to-digital converter (ADC) and then to the MCU main control circuit.

5. The device for detecting the voltage and current of the drive signal of the FAS gas cylinder solenoid valve according to claim 1, characterized in that, It also includes a human-machine interface and an audible and visual alarm circuit, both of which are connected to the MCU main control circuit and are used to display the measured voltage and current data and to issue an alarm when there is an abnormality.

6. The device for detecting the voltage and current of the drive signal of the FAS gas cylinder solenoid valve according to claim 1, characterized in that, It also includes a USB Type-C interface circuit, which is connected to a lithium battery charging management circuit for charging the lithium battery in the device.

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