CN211554130U - Intelligent safety power consumption monitoring device based on NB-IOT - Google Patents

Abstract

The utility model discloses a wisdom safety power consumption monitoring devices based on NB-IOT, the device includes: the intelligent control system comprises a power supply terminal (1), a communication terminal (2), an NB-IOT antenna interface (3), a power management (4), a 485 communication module (5), an NB-IOT module (6), a display module (7), an MCU (8), a key module (9), a three-phase voltage detection channel (10), a three-phase current detection channel (11), a three-phase cable temperature detection channel (12), a smoke detection channel (13) and a monitoring signal access terminal (14). The device can monitor the three-phase voltage, the three-phase current, the three-phase load line temperature and the smoke alarm condition of power consumption in real time, can transmit the alarm condition to a monitoring management platform through an NB-IOT module in a wireless mode, and has the flame-retardant characteristic on the shell.

Description

Intelligent safety power consumption monitoring device based on NB-IOT

Technical Field

The utility model is suitable for a need to detect the scene of safe power consumption, concretely relates to wisdom safe power consumption monitoring devices based on NB-IOT.

Background

At large-scale power consumption places such as communication computer lab, factory building, market, its power consumption peak period has very big demand to the power consumption, and the power consumption generally embodies through power consumption electric current, and when the power consumption was big, the power supply line current value risees, can lead to the power supply line to generate heat when transshipping, can take place the conflagration when serious. The traditional inspection mode is manual timing inspection, the current of each branch of the power distribution cabinet is tested through an isolation temperature measuring instrument and a current clamp, when the temperature of the branch is found to be high, potential safety hazards exist in the line diameter or a contact of the branch line, the line is replaced or the power consumption of the branch line is limited, real-time inspection of power consumption cannot be achieved, the potential safety hazards cannot be found in time when the power is consumed, and information is lagged.

To this problem, every branch road power consumption electric current size of switch board is measured to the accessible ammeter form, but the ammeter can only pass through RS485 form communication, if need with data upload to network platform and can long-rangely look over data, must additionally install information acquisition device additional, and the ammeter can only measure circuit electric current and voltage, can not measure circuit temperature and smog situation, and circuit temperature is the important parameter of judging whether there is the potential safety hazard, and smog situation indication line has the conflagration or not. The device can acquire voltage and current data and upload the voltage and current data to the cloud server in a 4G/WIFI mode, but the transmission mode of the device is greatly limited, the 4G transmission has high requirements on the system, the flow consumption is high, the relative cost is high, the WIFI mode has limitation on the network and the device cannot be used in the WIFI-free environment. In the era of the internet of things, the detection of the electricity safety expects a low-cost and movable device.

Disclosure of Invention

An object of the utility model is to provide an intelligent safety power consumption monitoring devices based on NB-IOT to the above-mentioned not enough of prior art. The utility model provides a scheme that its technical problem adopted is: the invention discloses an intelligent safety electricity monitoring device based on NB-IOT, which can monitor three-phase voltage, three-phase current, three-phase load line temperature and smoke alarm condition of a power distribution cabinet in real time, can be wirelessly transmitted to a monitoring management platform through an NB-IOT module, and has a flame retardant characteristic. As shown in fig. 1, the device comprises a power supply terminal, a communication terminal, an NB-IOT antenna interface, a power management, a 485 communication module, an NB-IOT module, a display module, an MCU, a key module, a three-phase voltage detection channel, a three-phase current detection channel, a three-phase line temperature detection channel, a smoke detection channel, and a monitor signal access terminal.

The power management provides a working power supply for the system, the system can independently supply power, the power supply voltage range is DC 9-24V, and 12V power supply is recommended. The power supply enters the management module through the power supply terminal and is transmitted to +5V through the small-sized switching power supply, and 5V is transmitted to 3.3V through the LDO. The +5V power supply supplies power to the 485 module and the key module, and the +3.3V power supply supplies power to the three-phase voltage detection channel, the three-phase current detection channel, the three-phase line temperature detection channel, the smoke detection channel and the NB-IOT module.

The 485 communication module mainly realizes the wired communication function of the device, communicates with external equipment through a communication terminal, can realize an external information sending interface of the detection device, and also serves as a cascade communication interface when a plurality of devices are expanded, and the 485 communication module realizes the electrical isolation of the device and the communication interface and prevents the influence of external electromagnetic interference on the normal work of the device.

The NB-IOT module is an interface for communication between the device and the network management platform, is connected with the MCU and the NB-IOT antenna interface, and an integrated module is selected in the module to realize conversion of serial TTL signals and wireless signals.

The display module and the key module are matched for use, the monitoring data checking and parameter setting functions are achieved, the key functions are respectively returning, confirming, moving upwards and moving downwards, the display module comprises an LCD display screen and an LED indicating lamp, the LCD display screen checks parameters and detailed information, and the LED is used for registering the visual display device on line, giving an alarm and running state.

The three-phase voltage detection channel adopts a voltage transformer form to sample alternating voltage signals, and the schematic diagram of a detection circuit is shown in figure 2. The primary side of the voltage transformer is strong current signals, the secondary side of the voltage transformer is weak current signals, a sampling resistor is added on a weak current signal line of the secondary side, the weak current signal line is converted into direct current signals through a rectifying and filtering circuit, and the direct current signals enter an MCU (microprogrammed control unit) for sampling after passing through a follower, so that the sampling of three-phase voltage is completed.

The three-phase current detection channel adopts an external open-close type current transformer, the acceptable input direct current voltage of the channel is 0-5V, and the current detection channel is shown in figure 3. The current transformer senses a current value, converts the current value into an alternating voltage signal and outputs the alternating voltage signal to the sampling channel, and the sampling channel receives the alternating voltage signal and then enters the MCU through the sorting filter, the low-pass filter and the following driver to finish sampling of the current signal. The current signal range can be set by software.

The three-phase cable temperature sensing channels may receive thermistor signals as shown in FIG. 4. The thermistor is fixed on the cable, the change of the temperature of the cable is fed back to the change of the resistance value of the thermistor, the impedance signal enters the impedance detection circuit and is converted into a direct current voltage signal, the direct current voltage signal enters the MCU through the low-pass filter, and the MCU searches the resistance value and temperature corresponding relation table to obtain the temperature of the cable.

The smoke detection channel is a switching value detection signal and can receive an external dry contact signal, namely a normally open or normally closed signal. The detection channel is provided with optical coupler isolation and filtering, and when high and low level signals are input from the outside, the rear end of the optical coupler can present standard TTL level signals and enter the MCU.

The monitoring signal access terminals are distributed as shown in fig. 5, and are respectively a three-phase voltage signal access terminal, a three-phase current signal access terminal, a three-phase temperature signal access terminal and an external power supply terminal from left to right, all the terminals are flame-retardant and screw-fixed terminals, and the safety of product design is ensured.

Drawings

FIG. 1 is a diagram of an intelligent safety power consumption monitoring device based on NB-IOT

FIG. 2 is a schematic diagram of a voltage detection channel

FIG. 3 is a schematic diagram of a current sensing channel

FIG. 4 is a schematic view of a temperature sensing channel

Fig. 5 is a diagram of a test signal access terminal profile.

Detailed Description

As shown in fig. 1, the present invention is composed of the following parts: the intelligent control system comprises a power supply terminal (1), a communication terminal (2), an NB-IOT antenna interface (3), a power management (4), a 485 communication module (5), an NB-IOT module (6), a display module (7), an MCU (8), a key module (9), a three-phase voltage detection channel (10), a three-phase current detection channel (11), a three-phase cable temperature detection channel (12), a smoke detection channel (13) and a monitoring signal access terminal (14).

The power supply terminal (1) uses a 3-bit fence type wiring terminal with protection, the power supply terminal is respectively connected with a single-phase live wire L, the single-phase zero wire is connected with N, a protected ground PE, the communication terminal (2) uses a 2-bit fence type wiring terminal with protection, the power supply terminal is respectively connected with an RS485 communication interface A and a monitoring signal terminal (14) uses a 20-bit fence type wiring terminal with protection, and the definitions of the monitoring signal terminal and the monitoring signal terminal are shown in figure 5 and respectively are voltage signal input, current signal input, temperature signal input and smoke sensor signal input.

The NB-IOT antenna interface (3) is a standard SMA bent angle antenna.

The power supply management (4) adopts a special 220VAC to +12VDC power supply, the output power of the power supply is 12W, and the power requirement of the whole machine can be met. The +12V power supply outputs +5V voltage after passing through a current chip TPS54331, the model of a Schottky diode added at the output end is MBRS360BT3G, the +5V power supply is converted into a +3.3V power supply after passing through a TLV1117LV33 power supply chip, and the 5V power supply and the 3.3V power supply are both used for supplying power to each module.

The 485 communication module (5) is the wired communication interface of the device to the outside, and the 485 chip that uses in the communication module is SP485, and the power supply of this chip is +5V, and the A and B of output are connected to communication terminal (2), and A and B are respectively through 4.7K pull-up resistance to +5V to stability when guaranteeing the bus idle. The 485 communication module is connected to the PD5 and the PD6 of the MCU and occupies the UART2 of the MCU.

The NB-IOT module (6) is a standard module component LTE BC95, the working voltage of the NB-IOT module is 5V, data interaction is carried out between the NB-IOT module and the MCU (8) through TTL level, and the antenna of the NB-IOT module is connected to the NB-IOT antenna interface, so that the MCU data can be transmitted and received wirelessly through the antenna.

The display module (7) is used as a man-machine interaction interface of the whole device, standard 12864 screens are used for displaying information, the display screen is communicated with the MCU through an IIC interface to obtain display data, functions such as data viewing, alarm viewing and parameter configuration can be realized on the display module, the display module (7) is matched with the key module (9) to be used together, the key module adopts standard matrix keyboard arrangement, the device is provided with 4 keys which are respectively used for determining, returning, turning up and turning down, one end of each key is connected to +3.3V, the other end of each key is directly connected to the MCU, when the keys are pressed down, the pin state of the MCU is triggered through high and low levels, the positions and the states of the keys are judged through programs in the MCU, and therefore the operation of a data menu is realized.

MCU (8) is the core of whole device information acquisition and processing, adopt STM32F207 chip as the master control, BOOT0 and BOOT1 that its started all are in and draw down the state, the system outside is equipped with hardware watchdog MAX706R, the controller uses outside 25M passive crystal oscillator as the clock source, the RC parameter of pin that resets is 10K ohm and 1uF electric capacity, for improving current-voltage sampling precision, the ADC benchmark adopts LM4040-3V, the current-limiting impedance is 300 ohm, the controller system adopts +3.3V power supply.

The three-phase voltage detection channel (10) is a channel for detecting mains voltage, a schematic diagram of a detection circuit of the three-phase voltage detection channel is shown in fig. 2, alternating mains voltage passes through a voltage transformer DL-PT202H1, an AC220V voltage signal is converted into a 4V alternating small signal, the 4V alternating small signal passes through a full-bridge rectification circuit MB6S and an RC low-pass filter circuit, the 4V alternating small signal is converted into a stable direct current signal, an operational amplifier LMV358 is used for building a following circuit, the isolation degree and the signal strength of a detection signal system are improved, the detection signal passes through the following circuit and enters a channel 1 of an ADC1 of an MCU for detection, a phase A, a phase B and a phase C phase voltage of the mains voltage respectively enter a channel 1/2/3 of the ADC1 for sampling, the MCU calculates an actual voltage value according to the transmission ratio of the voltage transformer, and the three-phase mains voltage A, the three-phase B, the three-phase C, Ub, Uc, N.

The three current detection channels (11) are channels for detecting the mains current, the schematic diagram of a detection circuit of the current detection channel is shown in fig. 3, the +12V of the working voltage of an external current transformer outputs a 2.5V +/-2V voltage signal, the voltage signal enters a following circuit built by LMV358 through a passive RC low-pass filter, the following circuit transmits the current signal to the 3 rd, 4 th and 5 th channels of an ADC1 of the MCU for sampling, the MCU calculates the current value according to the proportional value of the transformer, and the current transformers of the A phase, the B phase and the C phase of the three-phase mains supply are respectively connected to Ia +, Ia-, Ib +, Ib-, Ic + and Ic-of a monitoring signal access terminal (14).

The schematic diagram of a detection circuit of the three-temperature detection channel (12) device is shown in fig. 4, the three-temperature detection channel is externally connected with an NTC thermistor, two lines of the thermistor are connected to T and G of a detection interface, an MCU reversely calculates an NTC resistance value through impedance voltage, and the current temperature of the cable is calculated according to an internal temperature-impedance value mapping table.

The monitoring signal access terminal adopts a 20-bit fence type wiring terminal with protection, and the definition is shown in fig. 5, wherein Ua, Ub, Uc and N are respectively connected to an A phase, a B phase, a C phase and a zero line of three-phase mains voltage, Ia +, Ia-, Ib-, Ic + and Ic-are respectively connected to input signals of the three-phase mains current transformer, T1, G, T2, G, T3 and G are respectively connected to NTC detection lines for measuring the temperature of the three-phase mains cable, 12V and G supply power for a smoke inductor and a current transformer, C1/C2 are connected to a smoke inductor signal line, and the connected signals are dry contact signals.

Claims (2)

1. The utility model provides a wisdom safety power consumption monitoring devices based on NB-IOT, but the three-phase voltage of real-time supervision power consumption, three-phase current, three-phase load line temperature and smog alarm condition includes: power supply terminal (1), communication terminal (2), NB-IOT antenna interface (3), power management (4), 485 communication module (5), NB-IOT module (6), display module (7), MCU (8), button module (9), three-phase voltage detection passageway (10), three-phase current detection passageway (11), three-phase cable temperature detection passageway (12), smog detection passageway (13), monitor signal access terminal (14), its characterized in that: the power supply terminal (1) is interconnected with the power supply management (4) module, the power supply management (4) module is a 485 communication module (5), an NB-IOT module (6) and a display module (7), MCU (8), button module (9), three-phase voltage detection passageway (10), three-phase current detection passageway (11), three-phase cable temperature detection passageway (12), smog detection passageway (13) provide working power supply, 485 communication module (5) are connected with MCU (8) and communication terminal (2), NB-IOT module (6) are connected with NB-IOT antenna interface (3) and MCU (8), button module (9) and display module (7) are connected with MCU, three-phase voltage detection passageway (10), three-phase current detection passageway (11), three-phase cable temperature detection passageway (12), smog detection passageway (13) are connected in MCU (8) and monitor signal access terminal (14) respectively.

2. The NB-IOT based intelligent safety electricity monitoring device as claimed in claim 1, wherein: the device detects a three-phase voltage value, a three-phase current value, a three-phase cable temperature value and a smoke alarm condition, and uploads data through the NB-IoT module; the device can be cascaded together through an RS485 interface, and the expansion of a data acquisition channel is realized.

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