CN107256626A - Based on MBUS standard agreements collection water, heat, the method for gas meter - Google Patents
Based on MBUS standard agreements collection water, heat, the method for gas meter Download PDFInfo
- Publication number
- CN107256626A CN107256626A CN201710592667.9A CN201710592667A CN107256626A CN 107256626 A CN107256626 A CN 107256626A CN 201710592667 A CN201710592667 A CN 201710592667A CN 107256626 A CN107256626 A CN 107256626A
- Authority
- CN
- China
- Prior art keywords
- mbus
- voltage
- pin
- bit
- data
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08C—TRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILAR SIGNALS
- G08C19/00—Electric signal transmission systems
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Arrangements For Transmission Of Measured Signals (AREA)
Abstract
It is proposed by the present invention be it is a kind of based on MBUS standard agreements collection water, heat, the method for gas meter, this process employs based on MBUS standard protocol interface modules, the structure based on MBUS standard protocol interface modules includes transtation mission circuit unit, receiving circuit unit；Wherein, the transmission pin of microcontroller serial port is connected with the input pin of transtation mission circuit, the analog input pin of analog-digital converter is connected with the transmission pin of receiving circuit, the output pin of analog-digital converter is connected with the input pin of microcontroller serial port, the output pin of transtation mission circuit is connected with the input pin of water, air and heat table MBUS interfaces, and water, heat, the output pin of gas meter MBUS interfaces are connected with the input pin of receiving circuit.Advantages of the present invention：1）The band dynamic load of its circuit is more, strong antijamming capability；2）Receiving circuit samples to parse data using AD values, it is ensured that data are reliable；3）Cost is low.
Description
Technical field
Realize that standard MBUS protocol interfaces are used for gathering water meter, heat on electricity consumption acquisition terminal the present invention relates to one kind
The method of scale, gas meter data, and in particular to a kind of based on MBUS standard protocol interfaces module collection water, heat, the method for gas meter,
Belong to power information collection field.
Background technology
China is in automation building building cause booming period, and long-distance meter-reading system is as wherein important
One ring, just towards automation and intelligent direction development；MBUS (meter bus）Bus is as a kind of communication modes, with its high property
Valency ratio, is widely used in hydro-thermal measuring instrumentss, and the development of long-distance meter-reading system has been promoted significantly.
At present, many Integrated circuit manufacturers provide MBUS interface chips, the TSS 721 of such as Texas Instrument；These cores
Piece is widely used in MBUS communication kind equipments, but for some equipment to cost sensitivity, using this kind of chip
Device fabrication cost can undoubtedly be increased.
At present, using the operation of single-chip microcomputer control device in all kinds of intelligent measuring instruments, and all have in most of single-chip microcomputer
Standby ADC（Analog-digital converter）Module, therefore, single-chip microcomputer is utilized set forth herein one kind（STM32F407）ADC functions, coordinate outer
Portion's MBUS interface circuits, realization communicates with the MBUS of hydro-thermal table.
The content of the invention
Present invention proposition is a kind of based on MBUS standard agreements collection water, heat, the method for gas meter, and its purpose is intended to convenient and tool
Water, heat, the gas meter of standby MBUS interfaces are communicated.
The technical solution of the present invention：Based on MBUS standard agreements collection water, heat, the method for gas meter, this method is utilized
MBUS standard protocol interface modules are based on, structure based on MBUS standard protocol interface modules includes single-chip microcomputer, analog-to-digital conversion
Device, transtation mission circuit unit, receiving circuit unit；Wherein, the input pin phase of the transmission pin and transtation mission circuit of microcontroller serial port
Even, the analog input pin of analog-digital converter is connected with the transmission pin of receiving circuit, the output pin of analog-digital converter and
The input pin of microcontroller serial port is connected, the output pin He Shui of transtation mission circuit, heat, the input pin phase of gas meter MBUS interfaces
Even, water, the output pin of air and heat table MBUS interfaces are connected with the input pin of receiving circuit.
Advantages of the present invention：
1）Low voltage power line carrier meter reading terminal will be used for based on MBUS standard interface protocols so that power information collection can be square
Just copy reading MBUS interfaces water meter, hotlist, gas meter etc.；The band dynamic load of its circuit is more, and strong antijamming capability, circuit structure are simple,
It also can guarantee that data are normally received and sent in the case of severe；
2）Receiving circuit is sampled to parse data using AD values, and convenient also uncomplicated, optional single-chip microcomputer hardware is realized in software
It is required that also not high, the instant messaging failure short time can recover, it is ensured that data are reliable；
3）Special MBUS interface chips are not used, and are used centered on STM32F407, coordinate easy peripheral circuit to carry out mould
Intend MBUS data transmit-receives, realize the communication with slave station, simplify because receiving peripheral circuit, reduce cost, there is certain economy
Benefit.
Brief description of the drawings
Accompanying drawing 1 is the whole product frame principles schematic diagram of the present invention.
Accompanying drawing 2 is the application principle schematic diagram of the present invention.
Accompanying drawing 3 is the structural representation of transtation mission circuit unit.
Accompanying drawing 4 is the structural representation of receiving circuit unit.
Accompanying drawing 5 is ADC input pin voltage waveform.
Accompanying drawing 6 is the message oscillogram that slave station is sent.
Accompanying drawing 7 is the workflow diagram of whole algorithm.
Embodiment
Based on MBUS standard agreements collection water, heat, the method for gas meter, this process employs based on MBUS standard protocol interfaces
Module, the structure based on MBUS standard protocol interface modules includes transtation mission circuit unit, receiving circuit unit；Wherein, single-chip microcomputer
The transmission pin of serial ports is connected with the input pin of transtation mission circuit, the analog input pin of analog-digital converter and receiving circuit
Send pin to be connected, the output pin of analog-digital converter is connected with the input pin of microcontroller serial port, and the output of transtation mission circuit is drawn
Pin is connected with the input pin of water, air and heat table MBUS interfaces, water, heat, the output pin of gas meter MBUS interfaces and receiving circuit
Input pin is connected.
Described transtation mission circuit unit includes resistance, electric capacity, Xiao Jite diodes, voltage-regulator diode, NPN triode, P roads
Ditch FET, at the same outside access direct current 28V and 12V power supply, during MCU transmitting terminal input high levels, transtation mission circuit output
When 28V, MCU transmitting terminal input low level, transtation mission circuit output 12V sends pin by control single chip computer and reaches outside output
The purpose of data；Wherein, R19 is 5 Ω current sampling resistors, and effect is that current signal is converted into voltage signal, this sampling
The pressure drop on different R19 that resistance can be loaded and then can be different, and sends receiving circuit to；When MBUS sends high level letter
Number when, V5 conducting, VGS（The grid and voltage between source electrodes of FET）Voltage is, now
PMOS（P roads ditch FET）Q4 is turned on, MBUS0 TX（Long-distance meter-reading system is sent）End output high level；When MBUS is sent
During low level signal, V5 cut-offs, VGS voltages are 0V, and now Q4 ends, MBUS0 TX output low levels（12V）；R19 is 5 Ω electricity
Flow the voltage signal MBUS0- on sampling resistor, sampling resistor directly can carry out ADC after operational amplifier for MCU（Modulus turns
Parallel operation）Processing is converted into TTL through comparator（Logic level）MCU is supplied after level（Single-chip microcomputer）Processing；This sampling resistor meeting
And then the pressure drop on different R19 loaded can be different.
The receiving circuit unit includes sampling resistor, electric capacity, operational amplifier；Outside access direct current 5V power supplys, voltage
Signal is input to the reception pin of single-chip microcomputer by analog-digital converter after amplification, biasing；In MBUS transtation mission circuits,
MBUS receiving terminals input current signal is the MBUS0- on 0 ~ 20mA, sampling resistor（Long-distance meter-reading system receiving terminal）Amplitude is, then the signal be input in MBUS receiving circuits, by operational amplifier to signal carry out 20dB put
Greatly, amplified signal amplitude is 1V, the preferred SGM321 of model of operational amplifier.
Have capacitance C90 in the receiving circuit unit, capacitance C90 by MBUS buses because what quiescent current was caused
DC bias signal is excluded, and resistance R76, R77, R46 constitute amplifier DC bias circuit, and DC offset voltage is, operational amplifier multiplication factor isTimes, DC offset voltage is put by computing
Big device amplification is about 1.2V, when MBUS0- terminations receive signal, by C90 Capacitance Coupleds, then by amplifier amplification, will be believed
Number directly input MCU ADC（Analog-digital converter）, by MCU processing.
Algorithm is as a part for MBUS data functions, and its effect is that analog signal is converted into data signal, described to connect
Receive circuit unit and following algorithm mutual cooperation work：According to MBUS bus protocols, main website is by detecting in bus whether occur
11-20mA pulse currents determine to receive " 0 " still " 1 ", when there is pulse, represent " 0 ", are otherwise " 1 ", with reference to receiving circuit,
" 0 " is represented when ADC detects at least 0.5V voltage jump, is otherwise " 1 ".
After tested, ADC input pin voltage waveform is as shown in Figure 5；Whole slave station send message waveform as shown in fig. 6,
It can be seen that input voltage is progressively moved down, but voltage jump value keeps stable.
According to above-mentioned receiving voltage wave characteristics, the principle of whole algorithm is as follows：When main website is sent before data, bus is detected
The magnitude of voltage of overhead idle, and it is used as the reference voltage level that start bit is judged when receiving；After data are sent completely, to receiving data
Parsed, obtain correct data and used for single-chip microcomputer；
Specific resolving is as shown in Figure 7：Expected upper threshold value is set in ADC guards the gate dog pattern, ADC is enabled and interrupts,
Start ADC samplings；When bus voltage is uprised, and during more than upper threshold, then ADC interruptions can be triggered；Break service routine in the adc
In, close ADC and interrupt, and start timer interruption, interrupt cycle is half of time of bit, for gathering the electricity of start bit
Pressure value, in timer interrupt service program, calculates magnitude of voltage, than being then considered as data starting with reference to big more than the 0.5V of threshold voltage
The magnitude of voltage of position, and start timer interruption of the cycle for 1 bit time, gathered data, check bit and stop position；It is no
Then, start bit is detected again.
It is every in data bit for start bit and below, check bit, stop position in order to avoid the influence of noise in signal
Individual bit, the equal multiple repairing weld in its transmitting procedure, sampling number changes because of the change of baud rate, is then put down using median
The data that equal filtering algorithm processing is collected, obtain a reliable magnitude of voltage.
In order to adaptive different load, MBUS main websites are sent before data every time, collection voltages value as reference value,
And during subsequent receive, each bit magnitudes of voltage detected are made comparisons with reference value, and using this magnitude of voltage as new
Reference value, made comparisons with next bit magnitudes of voltage.Judge bit place values by calculating the change of magnitude of voltage, ensure that
Under different loads, the data of slave station can be properly received.
The MBUS is long-distance meter-reading system meter bus, and VGS is that FET is that grid is with voltage between source electrodes, TTL
Logic level, MBUS0 TX are that long-distance meter-reading system transmitting terminal, MCU are that single-chip microcomputer, ADC are analog-digital converter.
Claims (5)
1. based on MBUS standard agreements collection water, heat, the method for gas meter, it is characterized in that this process employs based on MBUS standards association
Discuss interface module, the structure based on MBUS standard protocol interface modules include single-chip microcomputer, analog-digital converter, transtation mission circuit unit,
Receiving circuit unit；Wherein, the transmission pin of microcontroller serial port is connected with the input pin of transtation mission circuit, the mould of analog-digital converter
Analog quantity input pin is connected with the transmission pin of receiving circuit, and the input of the output pin and microcontroller serial port of analog-digital converter is drawn
Pin is connected, and output pin He Shui, heat, the input pin of gas meter MBUS interfaces of transtation mission circuit are connected, and water, heat, gas meter MBUS connect
The output pin of mouth is connected with the input pin of receiving circuit.
2. it is according to claim 1 based on MBUS standard agreements collection water, heat, the method for gas meter, it is characterized in that described
Transtation mission circuit unit includes resistance, electric capacity, Xiao Jite diodes, voltage-regulator diode, NPN triode, P roads ditch FET, together
When outside access direct current 28V and 12V power supply, during MCU transmitting terminal input high levels, transtation mission circuit output 28V, MCU transmitting terminals
During input low level, transtation mission circuit output 12V, therefore the mesh that pin reaches outside output data is sent by control single chip computer
's；Wherein, R19 is 5 Ω current sampling resistors, and effect is that current signal is converted into voltage signal, and this sampling resistor can be with
The pressure drop on the different R19 of load can be different, and sends receiving circuit to；When MBUS sends high level signal, V5
Conducting, FET is that grid is with voltage between source electrodes voltage, now P roads ditch FET
Q4 is turned on, long-distance meter-reading system transmitting terminal output high level；When MBUS sends low level signal, V5 ends, and VGS voltages are
0V, now Q4 cut-offs, MBUS0 TX output low levels（12V）；R19 is the voltage letter on 5 Ω current sampling resistors, sampling resistor
After number MBUS0- directly can carry out analog-digital converter processing for MCU or be converted into Transistor-Transistor Logic level through comparator after operational amplifier
For single-chip microcomputer processing；The pressure drop on different R19 that this sampling resistor can be loaded and then can be different.
3. it is according to claim 1 based on MBUS standard agreements collection water, heat, the method for gas meter, it is characterized in that described connect
Receiving circuit unit includes sampling resistor, electric capacity, operational amplifier；Outside access direct current 5V power supplys, voltage signal, which passes through, to be amplified, partially
Postpone, the reception pin of single-chip microcomputer is input to by analog-digital converter；In MBUS transtation mission circuits, MBUS receiving terminal input currents
Signal is that the MBUS0- amplitudes on 0 ~ 20mA, sampling resistor are, signal is carried out using operational amplifier
20dB amplifies, and amplified signal amplitude is 1V, and then the voltage signal is output in MBUS receiving circuits.
4. it is according to claim 1 based on MBUS standard agreements collection water, heat, the method for gas meter, it is characterized in that described connect
Receiving has capacitance C90 in circuit unit, capacitance C90 believes the direct current biasing caused in MBUS buses because of quiescent current
Number exclude, resistance R76, R77, R46 constitute amplifier DC bias circuit, DC offset voltage is
, operational amplifier multiplication factor isTimes, DC offset voltage is about 1.2V by operational amplifier amplification, when
When MBUS0- terminations receive signal, by C90 Capacitance Coupleds, then by amplifier amplification, signal is directly inputted to MCU ADC
（Analog-digital converter）, by MCU processing.
5. it is according to claim 1 based on MBUS standard agreements collection water, heat, the method for gas meter, it is characterized in that described connect
Circuit unit and algorithm cooperating are received, specific algorithm is as follows：According to MBUS (meter bus) agreement, main website is by detecting bus
On whether occur 11-20mA pulse currents determine receive " 0 " still " 1 ", when there is pulse, represent " 0 ", be otherwise " 1 ", with reference to
Receiving circuit, " 0 " is represented when ADC detects at least 0.5V voltage jump, is otherwise " 1 "；
When main website is sent before data, the magnitude of voltage of bus overhead idle is detected, and is used as the reference electricity that start bit is judged when receiving
Pressure value；After data are sent completely, are parsed to receiving data, obtain correct data and used for single-chip microcomputer；
Expected upper threshold value is set in ADC guards the gate dog pattern, ADC is enabled and interrupts, starts ADC samplings；Work as bus voltage
Uprise, and during more than upper threshold, then can trigger ADC interruptions；Break in the adc in service routine, close ADC and interrupt, and start
Timer interruption, interrupt cycle is half of time of bit, for gathering the magnitude of voltage of start bit, in timer interrupt service
In program, magnitude of voltage is calculated, than being then considered as data start bit with reference to big more than the 0.5V of threshold voltage, and starts the cycle for 1 bit
The magnitude of voltage of the timer interruption of time, gathered data position, check bit and stop position；Otherwise, start bit is detected again；
It is each in data bit for start bit and below, check bit, stop position in order to avoid the influence of noise in signal
Bit, the equal multiple repairing weld in its transmitting procedure, sampling number changes because of the change of baud rate, is then averaged using median
The data that filtering algorithm processing is collected, obtain a reliable magnitude of voltage；
In order to adaptive different load, MBUS main websites are sent before data every time, collection voltages value as reference value, and
During then receiving, each bit magnitudes of voltage detected are made comparisons with reference value, and regard this magnitude of voltage as new ginseng
Value is examined, is made comparisons with next bit magnitudes of voltage；
Judge bit place values by calculating the change of magnitude of voltage, ensure that under different loads, can be properly received slave station
Data.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710592667.9A CN107256626A (en) | 2017-07-19 | 2017-07-19 | Based on MBUS standard agreements collection water, heat, the method for gas meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710592667.9A CN107256626A (en) | 2017-07-19 | 2017-07-19 | Based on MBUS standard agreements collection water, heat, the method for gas meter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107256626A true CN107256626A (en) | 2017-10-17 |
Family
ID=60026093
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710592667.9A Pending CN107256626A (en) | 2017-07-19 | 2017-07-19 | Based on MBUS standard agreements collection water, heat, the method for gas meter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107256626A (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108417002A (en) * | 2018-04-09 | 2018-08-17 | 南通德高环境监测技术有限公司 | A kind of high-performance MBUS collectors for water meter |
| CN108847100A (en) * | 2018-06-13 | 2018-11-20 | 郑州万特电气股份有限公司 | Four tables acquire fault simulation training apparatus |
| CN109302194A (en) * | 2018-11-29 | 2019-02-01 | 苏州东剑智能科技有限公司 | Mbus host receives circuit |
| CN109634897A (en) * | 2018-12-20 | 2019-04-16 | 宁波三星智能电气有限公司 | Based on the nonstandard MBUS communication means of discrete |
| CN109669378A (en) * | 2019-01-21 | 2019-04-23 | 武汉易维电子科技有限公司 | Dynamic threshold detection circuit, method and concentrator |
| CN109977062A (en) * | 2019-03-14 | 2019-07-05 | 建荣半导体（深圳）有限公司 | A kind of method, apparatus and electronic equipment of software realization Serial data receiving |
| CN110930682A (en) * | 2019-12-26 | 2020-03-27 | 宁波三星医疗电气股份有限公司 | MBUS communication circuit and MBUS communication system |
| CN112363964A (en) * | 2020-11-12 | 2021-02-12 | 深圳云顶智慧科技有限公司 | High-reliability MBUS (bus bar bus) host circuit |
| CN112583682A (en) * | 2020-12-25 | 2021-03-30 | 威胜集团有限公司 | Bus communication circuit and device |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES2191543A1 (en) * | 2000-11-17 | 2003-09-01 | Cahors App Elec | Domestic utility remote meter reading mechanism, having remote switch on mechanism sending measurement size and receivers receiving signal/converting bus with meter bus collecting digital words |
| CN102298345A (en) * | 2011-05-20 | 2011-12-28 | 深圳市骏普科技开发有限公司 | Communication method of M-BUS (meter-BUS) |
| CN203149372U (en) * | 2013-03-14 | 2013-08-21 | 吴兴中 | Digital intelligent M-bus concentrator based on single-chip microcomputer control |
| CN105809941A (en) * | 2016-03-15 | 2016-07-27 | 安阳工学院 | MBUS heat meter data collection controller and collection method |
| CN106683371A (en) * | 2016-11-23 | 2017-05-17 | 南京新联电子股份有限公司 | Electricity, water, gas and heat four-meter-into-one meter reading interface converter |
| CN206313786U (en) * | 2017-01-10 | 2017-07-07 | 国网江苏省电力公司苏州供电公司 | MBUS principal and subordinate's monitoring devices |
-
2017
- 2017-07-19 CN CN201710592667.9A patent/CN107256626A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES2191543A1 (en) * | 2000-11-17 | 2003-09-01 | Cahors App Elec | Domestic utility remote meter reading mechanism, having remote switch on mechanism sending measurement size and receivers receiving signal/converting bus with meter bus collecting digital words |
| CN102298345A (en) * | 2011-05-20 | 2011-12-28 | 深圳市骏普科技开发有限公司 | Communication method of M-BUS (meter-BUS) |
| CN203149372U (en) * | 2013-03-14 | 2013-08-21 | 吴兴中 | Digital intelligent M-bus concentrator based on single-chip microcomputer control |
| CN105809941A (en) * | 2016-03-15 | 2016-07-27 | 安阳工学院 | MBUS heat meter data collection controller and collection method |
| CN106683371A (en) * | 2016-11-23 | 2017-05-17 | 南京新联电子股份有限公司 | Electricity, water, gas and heat four-meter-into-one meter reading interface converter |
| CN206313786U (en) * | 2017-01-10 | 2017-07-07 | 国网江苏省电力公司苏州供电公司 | MBUS principal and subordinate's monitoring devices |
Non-Patent Citations (2)
| Title |
|---|
| 李敏 等: "基于MSP430和M-BUS的标准远传抄表系统设计", 《现代工程制造》 * |
| 金晨雨 等: "基于M-BUS总线的热力站监测系统", 《仪器仪表用户》 * |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108417002A (en) * | 2018-04-09 | 2018-08-17 | 南通德高环境监测技术有限公司 | A kind of high-performance MBUS collectors for water meter |
| CN108847100B (en) * | 2018-06-13 | 2023-09-26 | 郑州万特电气股份有限公司 | Four-meter acquisition fault simulation training equipment |
| CN108847100A (en) * | 2018-06-13 | 2018-11-20 | 郑州万特电气股份有限公司 | Four tables acquire fault simulation training apparatus |
| CN109302194A (en) * | 2018-11-29 | 2019-02-01 | 苏州东剑智能科技有限公司 | Mbus host receives circuit |
| CN109302194B (en) * | 2018-11-29 | 2023-10-20 | 苏州东剑智能科技有限公司 | Mbus host receiving circuit |
| CN109634897A (en) * | 2018-12-20 | 2019-04-16 | 宁波三星智能电气有限公司 | Based on the nonstandard MBUS communication means of discrete |
| CN109669378B (en) * | 2019-01-21 | 2023-10-10 | 武汉易维科技股份有限公司 | Dynamic threshold detection circuit, method and concentrator |
| CN109669378A (en) * | 2019-01-21 | 2019-04-23 | 武汉易维电子科技有限公司 | Dynamic threshold detection circuit, method and concentrator |
| CN109977062A (en) * | 2019-03-14 | 2019-07-05 | 建荣半导体（深圳）有限公司 | A kind of method, apparatus and electronic equipment of software realization Serial data receiving |
| CN110930682A (en) * | 2019-12-26 | 2020-03-27 | 宁波三星医疗电气股份有限公司 | MBUS communication circuit and MBUS communication system |
| CN112363964A (en) * | 2020-11-12 | 2021-02-12 | 深圳云顶智慧科技有限公司 | High-reliability MBUS (bus bar bus) host circuit |
| CN112363964B (en) * | 2020-11-12 | 2024-03-19 | 深圳云顶智慧科技有限公司 | MBUS host circuit with high reliability |
| CN112583682A (en) * | 2020-12-25 | 2021-03-30 | 威胜集团有限公司 | Bus communication circuit and device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107256626A (en) | Based on MBUS standard agreements collection water, heat, the method for gas meter | |
| CN102298345B (en) | Communication method of M-BUS (meter-BUS) | |
| CN201438208U (en) | Online detecting device of on-off control return circuit of circuit breaker | |
| CN202166856U (en) | Slave receiving circuit of M-BUS | |
| CN204578211U (en) | The system that a kind of transformer presence detects | |
| CN102496904B (en) | A kind of Self-powered communication-bus short-circuit protection method | |
| CN103634723A (en) | Audio input circuit and electronic device with audio input | |
| CN206178800U (en) | M bus bus host computer circuit | |
| CN111223286A (en) | Meter BUS-based data acquisition device and method | |
| CN202548231U (en) | Detection device for substation merging unit | |
| CN203573477U (en) | Effective wireless monitoring data receiving/transmitting device for grain drying equipment | |
| CN206489708U (en) | MBUS telecommunication circuits and its measuring instrument being made | |
| CN202797865U (en) | Short circuit protector of M-BUS communication bus | |
| CN204989389U (en) | Earth fault positioning circuit of direct current test system | |
| CN201145846Y (en) | Apparatus for monitoring electric fire disaster | |
| CN211427481U (en) | Function detection device for electricity consumption information acquisition terminal | |
| CN207991999U (en) | High precision two line system industrial dust detection device | |
| CN207835500U (en) | A kind of detecting system monitoring communication module based on cloud | |
| CN105352138B (en) | Method and device for monitoring communication between internal machine and external machine of variable frequency air conditioner and air conditioning system | |
| CN205540076U (en) | Intelligence supervisory circuits | |
| CN204631186U (en) | A kind of phase three-wire three supply line decompression calculagraph | |
| CN204465547U (en) | A kind of radio monitoring receiver with self-checking function | |
| CN217985102U (en) | Power communication network safety management device | |
| CN204405218U (en) | Wide region is powered Pt1000 temperature transmitter | |
| CN211349035U (en) | Equipment dynamic monitoring and fault early warning system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20171017 |
|
| WD01 | Invention patent application deemed withdrawn after publication |