CN207503216U - MBUS communication switching circuits - Google Patents

MBUS communication switching circuits Download PDF

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Publication number
CN207503216U
CN207503216U CN201721745443.9U CN201721745443U CN207503216U CN 207503216 U CN207503216 U CN 207503216U CN 201721745443 U CN201721745443 U CN 201721745443U CN 207503216 U CN207503216 U CN 207503216U
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China
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mbus
circuit
signal
controller
relay
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CN201721745443.9U
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贺驰光
汤可
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Wasion Information Technology Ltd By Share Ltd
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Wasion Information Technology Ltd By Share Ltd
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Abstract

The utility model discloses a kind of MBUS communication switching circuits, including slave interface detection circuit, level shifting circuit, controller, drive signal generation circuit and the relay circuit being sequentially connected in series;From interface detection circuit detection from the working condition of MBUS communication lines on MBUS interfaces and send out detection signal pass through input controller after level shifting circuit switching levels;Controller output control signal drives relay circuit to work by drive signal generation circuit, realizes the switching of MBUS telecommunication circuits.The utility model realizes the free switching of the communication interface between MBUS meters, MBUS collectors and MBUS converters by relay circuit and corresponding drive signal generation circuit, and occupy few controller hardware and software resource, and circuit is simple and reliable, it is of low cost.

Description

MBUS communication switching circuits
Technical field
The utility model is more particularly to a kind of MBUS communication switching circuits.
Background technology
With the development and the improvement of people's living standards of national economy technology, bus communication technology has become industry Essential means of communication in production and electric/electronic device.MBUS buses are widely used in the meterings such as water meter, ammeter or gas meter In instrument, the important function of data communication carry.
At present, four table collection copy (ammeter, water meter, gas meter and hotlist) application it is more and more extensive.At present, it is copied in four table collection and is In system, the conversion of MBUS interfaces is carried out frequently with converter.Converter has main MBUS interfaces and from MBUS interface, is total to two-way MBUS interfaces.MBUS meters are hung on the main MBUS interfaces of converter, and the slave MBUS that MBUS collectors are then articulated in converter connects On mouth.During normal work, the controller in converter passes through the direct copy reading meter of main MBUS interfaces;If MBUS collectors needs are copied Meter reading meter, then converter preferentially by principal and subordinate MBUS interfaces be connected, provide access, function mould for MBUS collectors and MBUS meters Block diagram is as shown in Figure 1.
At present, on the market frequently with the main MBUS interfaces of converter to connect with the conversion from MBUS interfaces be all using turning The form of parallel operation software forward communication message builds communication path for MBUS collectors and MBUS meters.But software forward Mode not only increases the programming difficulty (needing to identify baud rate, message etc.) of the control system of converter, also occupies conversion The hardware and software resource of device control system.
Utility model content
The purpose of this utility model is to provide a kind of hardware and software resource for occupying converter is few, and simply may be used The MBUS communication switching circuits leaned on.
This MBUS communication switching circuit provided by the utility model, including controller, further include from interface detection circuit, Level shifting circuit, drive signal generation circuit and relay circuit;From interface detection circuit, level shifting circuit, controller, Drive signal generation circuit and relay circuit are sequentially connected;The MBUS communication lines connection of MBUS collectors detects electricity from interface Road;From interface detection circuit for detecting the working condition from MBUS communication lines on MBUS interfaces, and when from MBUS interfaces The work of MBUS buses when send out detection signal to level shifting circuit;Level shifting circuit is believed signal is detected by MBUS level It number is converted to the controller level signal that controller can identify and is input to controller;Controller is according to the slave MBUS detected The output of interfaces status signal controls signal to drive signal generation circuit all the way;Drive signal generation circuit is according to controller The control signal sent out generates drive signal driving relay circuit work;Relay circuit will according to the drive signal received The main MBUS interfaces of converter are directly connected with from MBUS interfaces, so as to fulfill the switching of MBUS telecommunication circuits.
The slave interface detection circuit is rectifier circuit;Rectifier circuit will communicate from the MBUS on MBUS interfaces to be believed Number be converted to the level signal of positive polarity, and with the level signal instruction of the positive polarity from the MBUS communication lines on MBUS interfaces It is working.
The level shifting circuit is the level shifting circuit being made of opto-coupler chip;Level shifting circuit is used to examine Signal is surveyed to be converted to controller level signal that controller can identify by MBUS level signals and be input to controller.
The drive signal generation circuit includes the signal generating circuit and signal drive circuit that are sequentially connected in series;Signal produces Raw circuit connection controller, the control signal sent out for identification controller and the corresponding control drive signal of generation to signal drive Dynamic circuit;After signal drive circuit receives control drive signal, the drive signal that relay can be driven to work all the way is generated To relay circuit.
The drive signal generation circuit further includes isolation circuit;Isolation circuit is serially connected in controller and generates electricity with signal Between road, it is electrically connected for direct between isolation controller and signal generating circuit, so as to protect controller.
The signal generating circuit includes first switch pipe and first switch pipe current-limiting resistance;The control of controller output Signal connects the control terminal of first switch pipe by first switch pipe current-limiting resistance, and movable end one end of first switch pipe is grounded, The output terminal of the movable end other end of first switch pipe drive signal in order to control.
The signal drive circuit includes second switch pipe, second switch pipe current-limiting resistance and second switch pipe pull-up electricity Resistance;The control terminal of second switch pipe is directly connected to the output terminal of signal generating circuit, simultaneously also by second switch pipe current limliting electricity Resistance connects relay power anode with second switch pipe pull-up resistor;Movable end one end of second switch pipe passes through second switch pipe Pull-up resistor connects relay power anode, and the movable end other end of second switch pipe is then the output terminal of signal drive circuit.
The relay circuit is to form circuit by the relay of two pairs of normally opened nodes and two pairs of normally closed nodes;Relay Coil electrode connection drive signal generation circuit output terminal, relay coil cathode ground connection;First activity of relay Node and the second active node connect the MBUS anode communication lines of MBUS measuring instruments respectively, the first normally closed node of relay and Second normally closed node connects the MBUS anode communication lines of the slave MBUS interfaces of MBUS converters, the first normally opened section of relay simultaneously Point connects the MBUS anode communication lines of controller MBUS interfaces with the second normally opened node, and the MBUS cathode of controller MBUS interfaces lead to Letter line is shorted together from the MBUS cathode communication line of MBUS interfaces and the MBUS cathode communication line of meter.
This MBUS communications switching circuit provided by the utility model, is produced by relay circuit and corresponding drive signal The freedom that raw circuit is realized between MBUS meters, MBUS collectors and MBUS converters switches, and protect when power is off at any time Being directly connected to for MBUS meters and MBUS collectors is demonstrate,proved;Switching circuit provided by the utility model can not only realize MBUS The switching of communication line, and few controller hardware and software resource are occupied, and circuit is simple and reliable, it is of low cost.
Description of the drawings
Fig. 1 is the functional block diagram of the converter of the prior art.
Fig. 2 is the functional block diagram of the utility model.
Fig. 3 is the slave interface detection circuit of the utility model and the circuit theory schematic diagram of level shifting circuit.
Fig. 4 is the circuit theory schematic diagram of the drive signal generation circuit of the utility model.
Fig. 5 is the circuit theory schematic diagram of the relay circuit of the utility model.
Specific embodiment
It is illustrated in figure 2 the functional block diagram of the utility model:This MBUS communications switching electricity provided by the utility model Road including controller, is further included from interface detection circuit, level shifting circuit, drive signal generation circuit and relay circuit; It is sequentially connected from interface detection circuit, level shifting circuit, controller, drive signal generation circuit and relay circuit;MBUS The MBUS communication lines of collector are connected from interface detection circuit;It is used to detect from MBUS on MBUS interfaces from interface detection circuit The working condition of communication line, and when from MBUS interfaces MBUS buses work when send out detection signal to level conversion electricity Road;Level shifting circuit will detect signal and be converted to controller level signal that controller can identify simultaneously by MBUS level signals It is input to controller;Controller according to the slave MBUS interfaces status signal output detected, believe all the way by control signal to driving Number generation circuit;Drive signal generation circuit generates drive signal driving relay circuit according to the control signal that controller is sent out Work;Relay circuit directly connects the main MBUS interfaces of converter with from MBUS interfaces according to the drive signal received, So as to fulfill the switching of MBUS telecommunication circuits.
It is illustrated in figure 3 the slave interface detection circuit of the utility model and the circuit theory schematic diagram of level shifting circuit: It is rectifier circuit from interface detection circuit (BR1 is rectifier bridge in figure);Rectifier circuit will be from the MBUS on MBUS interfaces Signal of communication (being SLAVE_MBUS1 and SLAVE_MBUS2 shown in figure) is converted to the level signal SLAVE_MBUS of positive polarity +, and worked with the level signal instruction of the positive polarity from the MBUS communication lines on MBUS interfaces;Level shifting circuit is The level shifting circuit being made of opto-coupler chip;1 foot of input terminal of opto-coupler chip passes through current-limiting resistance R1 connections SLAVE_MBUS+ Signal, 2 foot of input terminal of opto-coupler chip is then by the ground terminal of pull down resistor R2 connection rectifier bridges, while also connection MBUS- letters Number, it is connected with filter capacitor C1 between 1 foot and 2 feet of opto-coupler chip;3 foot of reception pipe of opto-coupler chip is directly grounded, and 4 feet then lead to Cross pull-up resistor R3 connection positive poles (V3P3), while also output detection signal SLAVE_DET;Level shifting circuit is used for will Detection signal is converted to controller level signal that controller can identify by MBUS level signals and is input to controller.
The operation principle of foregoing circuit is as follows:MBUS converters slave MBUS interfaces (shown in figure for SLAVE_MBUS1 and SLAVE_MBUS2 MBUS collectors) are connected;During due to MBUS line works, the level signals of MBUS+ pins can be high level or Low level;As long as therefore MBUS line works, then 3 foot of output terminal of rectifier bridge will export the SLAVE_MBUS being not zero all the way + signal, the road signal be not zero the MBUS collectors for showing to be connected from MBUS interfaces need carry out data acquisition;The road refers to Show 1 foot of the signal by current-limiting resistance R1 connection optocouplers D1, be pulled low to low electricity since 2 feet of optocoupler are pulled down resistance R2 at this time Flat, the transmitting tube conducting of optocoupler D1 at this time, 3 feet of the reception pipe of optocoupler and 4 feet are directly connected at this time, and SLAVE_DET believes at this time Number low level signal and to be input in controller, instruction needs to carry out data to adopt from the MBUS collectors on MBUS interfaces at this time Collection.
And when the MBUS collectors connected from MBUS interfaces do not need to gathered data, MBUS data collectors at this time MBUS will not work, then the output terminal SLAVE_MBUS+ of rectifier bridge BR1 is low level, and the transmitting tube of optocoupler D1 is not turned at this time, Reception pipe is also not turned on, and SLAVE_DET is pulled up resistance R3 and draws high to high level signal at this time, shows at this time from MBUS interfaces MBUS collectors do not need to carry out data acquisition.
The effect of optocoupler is to realize between MBUS level and the level signal (V3P3 shown in figure) that control can identify Level signal convert with being isolated.
It is illustrated in figure 4 the circuit theory schematic diagram of the drive signal generation circuit of the utility model:Drive signal generates Circuit includes the isolation circuit, signal generating circuit and the signal drive circuit that are sequentially connected in series.
Isolation circuit is the isolation circuit being made of optocoupler D2:The control that device generates in order to control of SLAVE_MBUS_CTL signals Signal;The control signal that controller generates is directly connected to 2 feet of optocoupler D2, is controlled simultaneously also by optocoupler pull-up resistor R4 connections Device positive pole V3P3;1 foot of optocoupler D2 connects controller power source anode V3P3 by inputting pull-up circuit;The reception pipe of optocoupler 4 feet are directly connected to 5V positive poles (being illustrated as V5P0_ISO), and 3 foot of reception pipe of optocoupler then exports the control letter by isolation Number.
Signal generating circuit includes first switch pipe V1 and first switch pipe current-limiting resistance R6;The control letter of controller output After number being isolated by isolation circuit, by 1 foot of control terminal of first switch pipe current-limiting resistance R6 connection first switch pipes V1, first The movable end one end 2 foot ground connection of switching tube, the output terminal of 3 foot of the movable end other end of first switch pipe drive signal in order to control.
Signal driver circuit includes second switch pipe V2, second switch pipe current-limiting resistance R7 and second switch pipe pull-up resistor R8;The control terminal of second switch pipe is directly connected to the output terminal of signal generating circuit, simultaneously also by second switch pipe current limliting electricity Resistance R7 connects relay power anode (diagram V12P0_ISO) with second switch pipe pull-up resistor R8;The activity of second switch pipe Holding one end, the movable end other end of second switch pipe is then by second switch pipe pull-up resistor R8 connection relay power anodes The output terminal of signal drive circuit is grounded simultaneously also by filter capacitor C2.
The course of work of above-mentioned drive signal generation circuit is as follows:
Controller is according to the detection signal of the slave interface detection circuit of reception, if being needed from the MBUS collectors on MBUS interfaces Data acquisition is carried out, then the control signal SLAVE_MBUS_CTL of controller output is the 2 of low level signal, at this time optocoupler D2 Foot is pulled low to low level, at this time the transmitting tube conducting of optocoupler so that 3 foot of reception pipe of optocoupler and 4 feet are directly connected, and open at this time The base stage for closing pipe V1 is high level signal, and 2 foot of emitter of switching tube V1 is low level signal, and switching tube V1 is connected at this time, opens 2 feet and 3 feet for closing pipe V1 are directly connected so that the control terminal of switching tube V2 is pulled low to low level;And due to switching tube V2's Source electrode is drawn high by resistance R8 to high level, therefore switching tube V2 is connected, and the drain electrode of switching tube V2 at this time is directly drawn high by resistance R8 To high level so that RELAY_CTL signals are high level and output valve relay circuit.
If it does not need to carry out data acquisition, the control signal of controller output from the MBUS collectors on MBUS interfaces SLAVE_MBUS_CTL is high level signal, and 2 feet of optocoupler D2 are pulled to high level at this time, and the transmitting tube of optocoupler is cut at this time Only so that 3 foot of reception pipe of optocoupler and 4 feet are not turned on, at this time the base stage of switching tube V1 be low level signal, the hair of switching tube V1 2 foot of emitter-base bandgap grading is also low level signal, and switching tube V1 ends at this time, 2 feet of switching tube V1 and the cut-off of 3 feet so that switching tube V2's Control terminal is pulled to high level;And since the source electrode of switching tube V2 is drawn high by resistance R8 to high level, switching tube V2 is cut Only, the drain electrode of switching tube V2 at this time is also low level so that RELAY_CTL signals are low level and output valve relay circuit.
It is illustrated in figure 5 the circuit theory schematic diagram of the relay circuit of the utility model:Relay circuit is by two pairs The relay of normally opened node and two pairs of normally closed nodes forms circuit;1 foot of the coil electrode connection drive signal of relay generates electricity The output terminal (being illustrated as REALY_CTL) on road, 16 foot of coil cathode of relay are directly grounded;First active node of relay 4 feet and 13 foot of the second active node connect the MBUS anode communication lines of MBUS measuring instruments, the first normally closed section of relay respectively 6 feet of point and the second normally closed 11 foot of node connect MBUS anodes communication line (the diagram letter of the slave MBUS interfaces of MBUS converters simultaneously Number it is SLAVE_MBUS+), the first normally opened 8 foot of node of relay and the second normally opened 9 foot of node connection controller MBUS interfaces MBUS anodes communication line (diagram signal be MBUS1+ and MBUS2+), the MBUS cathode communication line of controller MBUS interfaces, from The MBUS cathode communication line of MBUS interfaces and the MBUS cathode communication lines of meter are shorted together.
The operation principle of above-mentioned relay circuit is:
When RELAY_CTL signals are high level, the coil of relay K1 obtains electric at this time, and normally closed node disconnects at this time, often Node closure is opened, 4 feet of relay and 8 feet link together at this time, and 9 feet and 13 feet link together;Therefore under this kind of operating mode: The MBUS anodes communication line of the MBUS interfaces of the MBUS anodes communication line of MBUS measuring instruments and the controller of converter inside connects It is connected together, at this time the data of the normal copy reading MBUS measuring instruments of converter.
As RELAY --- when CTL signals are low level, the coil losing electricity of relay K1 at this time, at this time normally closed node be closed, Normally opened node disconnects (situation to that indicated in the drawings is identical);4 feet of relay and 6 feet link together at this time, and 13 feet and 11 feet connect It is connected together;Therefore under this kind of operating mode:The MBUS anodes communication line of MBUS measuring instruments and the anode communication line of MBUS collectors It links together, MBUS collectors are directly from MBUS measuring instrument gathered datas at this time.
In addition, if converter is in the abnormalities such as failure or power down, the control of the controller output of converter at this time Signal is low level, therefore RELAY_CTL signals are low level, equally ensure that the MBUS anode communication lines of MBUS measuring instruments It links together with the anode communication line of MBUS collectors, MBUS collectors are directly from MBUS measuring instrument gathered datas at this time.

Claims (8)

  1. The switching circuit 1. a kind of MBUS communicates, including controller, it is characterised in that further include from interface detection circuit, level conversion Circuit, drive signal generation circuit and relay circuit;From interface detection circuit, level shifting circuit, controller, drive signal Generation circuit and relay circuit are sequentially connected;The MBUS communication lines of MBUS collectors are connected from interface detection circuit;From connecing Mouth detection circuit is worked as total from the MBUS on MBUS interfaces for detecting the working condition from MBUS communication lines on MBUS interfaces Line sends out detection signal to level shifting circuit when working;Level shifting circuit is converted to signal is detected by MBUS level signals Controller level signal that controller can identify simultaneously is input to controller;Controller is according to the slave MBUS interfaces detected Status signal output controls signal to drive signal generation circuit all the way;The control that drive signal generation circuit is sent out according to controller Signal processed generates drive signal driving relay circuit work;Relay circuit is according to the drive signal received by converter Main MBUS interfaces are directly connected with from MBUS interfaces, so as to fulfill the switching of MBUS telecommunication circuits.
  2. The switching circuit 2. MBUS according to claim 1 communicates, it is characterised in that described from interface detection circuit is whole Flow bridge circuit;The level signal that rectifier circuit will be converted to positive polarity from the MBUS signals of communication on MBUS interfaces, and with this The level signal instruction of positive polarity is working from the MBUS communication lines on MBUS interfaces.
  3. The switching circuit 3. MBUS according to claim 2 communicates, it is characterised in that the level shifting circuit is by light The level shifting circuit that coupling chip is formed;Level shifting circuit is converted to controller for that will detect signal by MBUS level signals The controller level signal that can identify simultaneously is input to controller.
  4. 4. the MBUS communication switching circuits according to one of claims 1 to 3, it is characterised in that the drive signal generates Circuit includes the signal generating circuit and signal drive circuit that are sequentially connected in series;Signal generating circuit connects controller, for identifying The control signal and generation that controller is sent out control drive signal to signal drive circuit accordingly;Signal drive circuit receives After controlling drive signal, generation can drive the drive signal that relay works to relay circuit all the way.
  5. The switching circuit 5. MBUS according to claim 4 communicates, it is characterised in that the drive signal generation circuit is also Including isolation circuit;Isolation circuit is serially connected between controller and signal generating circuit, is generated for isolation controller and signal Direct electrical connection between circuit, so as to protect controller.
  6. The switching circuit 6. MBUS according to claim 5 communicates, it is characterised in that the signal generating circuit includes the One switching tube and first switch pipe current-limiting resistance;The control signal of controller output passes through first switch pipe current-limiting resistance connection the The control terminal of one switching tube, movable end one end ground connection of first switch pipe, the movable end other end of first switch pipe drive in order to control The output terminal of dynamic signal.
  7. The switching circuit 7. MBUS according to claim 6 communicates, it is characterised in that the signal drive circuit includes the Two switching tubes, second switch pipe current-limiting resistance and second switch pipe pull-up resistor;The control terminal of second switch pipe is directly connected to letter The output terminal of number generation circuit, relay is connected simultaneously also by second switch pipe current-limiting resistance with second switch pipe pull-up resistor Positive pole;Movable end one end of second switch pipe by second switch pipe pull-up resistor connect relay power anode, second The movable end other end of switching tube is then the output terminal of signal drive circuit.
  8. The switching circuit 8. MBUS according to claim 7 communicates, it is characterised in that the relay circuit is by two pairs The relay of normally opened node and two pairs of normally closed nodes forms circuit;The coil electrode connection drive signal generation circuit of relay Output terminal, the coil cathode ground connection of relay;The first active node and the second active node of relay connect MBUS meters respectively The MBUS anode communication lines of instrument are measured, the first normally closed node and the second normally closed node of relay connect MBUS converters simultaneously From the MBUS anode communication lines of MBUS interfaces, the first normally opened node of relay and the second normally opened node connection controller MBUS connect The MBUS anode communication lines of mouth, the MBUS cathode communication line of controller MBUS interfaces, the MBUS cathode communication lines from MBUS interfaces It is shorted together with the MBUS cathode communication line of meter.
CN201721745443.9U 2017-12-14 2017-12-14 MBUS communication switching circuits Active CN207503216U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201721745443.9U CN207503216U (en) 2017-12-14 2017-12-14 MBUS communication switching circuits

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201721745443.9U CN207503216U (en) 2017-12-14 2017-12-14 MBUS communication switching circuits

Publications (1)

Publication Number Publication Date
CN207503216U true CN207503216U (en) 2018-06-15

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Application Number Title Priority Date Filing Date
CN201721745443.9U Active CN207503216U (en) 2017-12-14 2017-12-14 MBUS communication switching circuits

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110246322A (en) * 2019-05-21 2019-09-17 安徽南瑞中天电力电子有限公司 A kind of MBUS water meter collection copies switching circuit

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110246322A (en) * 2019-05-21 2019-09-17 安徽南瑞中天电力电子有限公司 A kind of MBUS water meter collection copies switching circuit

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