Modbus RTU raws tu qauv yog zoo li "ib hom lus" ntawm cov khoom siv hauv kev lag luam, ua kom zoo "kev sib txuas lus" ntawm cov khoom siv xws li cov ntsuas hluav taws xob thiab cov sensors los ntawm ntau hom.
Modbus Communication Protocol Application Demonstration
Kab lus no yuav coj koj los ntawm daim ntawv thov ntawm Modbus RTU hauv cov ntsuas hluav taws xob hauv txoj kev yooj yim thiab nkag siab tshaj plaws. Txawm hais tias koj yog ib tus neeg tshiab tshiab uas tsis muaj keeb kwm yav dhau los, koj tuaj yeem nkag siab cov ntsiab lus tseem ceeb ntawm cov txheej txheem kev sib txuas lus tseem ceeb no.
Modbus RTU raws tu qauv yog dab tsi?
Modbus RTU yog ib qho kev sib txuas lus sib txuas lus thawj zaug tsim los ntawm Modicon (tam sim no ib feem ntawm Schneider Electric) hauv 1979 rau nws cov PLCs (Programmable Logic Controllers).
Niaj hnub no, nws tau dhau los ua ib qho ntawm feem ntau siv raws tu qauv hauv kev lag luam automation, txhawb nqa los ntawm ntau tshaj 400 manufacturers thoob ntiaj teb.
Vim li cas thiaj hu ua "RTU"? RTU yog ib lo lus luv luv rau "Tswj Vaj Huam Sib Luag", qhia tias cov txheej txheem no feem ntau yog siv rau kev sib txuas lus ntawm cov chaw taws teeb. Nws zoo li "texting system" ntawm cov khoom siv hluav taws xob, sib pauv cov ntaub ntawv los ntawm kev thov yooj yim thiab cov txheej txheem teb.
Modbus RTU ua haujlwm li cas?
Modbus RTU siv tus tswv- qhev kev sib txuas lus architecture, zoo li tus kws qhia ntawv thiab cov tub ntxhais kawm hauv chav kawm.
- Master: Tus "xib fwb," feem ntau yog lub khoos phis tawj, PLC, lossis tus neeg saib xyuas, yog lub luag haujlwm los pib cov lus nug thiab cov lus txib.
- qhev: "tus tub kawm ntawv," xws li lub ntsuas hluav taws xob lossis lub ntsuas hluav taws xob, tsuas tuaj yeem teb tus xibfwb cov lus nug thiab hais tsis tau nws tus kheej. (Hauv kev siv hluav taws xob ntsuas hluav taws xob ...)
Modbus RTU lus Format
"SMS Template" nruab nrab ntawm cov khoom siv
Modbus RTU cov lus sib txuas lus zoo ib yam li cov ntawv sau ua tib zoo, nrog rau cov kev xav tau ruaj khov.
Ib tsab ntawv Modbus RTU tiav muaj cov hauv qab no:
| Chaw nyob Code | Function Code | Data Field | Kuaj Code |
|---|---|---|---|
| 8-Bit | 8-Bit | N × 8-Bits | 16- Ib |
- Chaw Nyob Code (1 byte): Sib npaug rau "tus neeg txais xov tooj," txheeb xyuas qhov chaw nyob ntawm lub hom phiaj lub zog ntsuas (1-247), nrog 0 rau qhov chaw nyob tshaj tawm.
- Function Code (1 byte): Sib npaug rau "cov ntawv xov xwm", qhia lub zog ntsuas ntawm kev ua haujlwm ua haujlwm (xws li, nyeem cov ntaub ntawv, sau cov ntaub ntawv, thiab lwm yam).
- Cov Ntaub Ntawv Field (N bytes): Cov ntaub ntawv tshwj xeeb yuav tsum tau xa tawm, xws li chaw nyob sau npe, tus nqi cov ntaub ntawv, thiab lwm yam.
- CRC Checksum (2 bytes): Sib npaug rau "anti-cov lej cuav," siv los kuaj xyuas qhov tsis raug thaum kis.
Ib cov lus zoo rau kev nyeem tag nrho cov ntaub ntawv muaj zog zoo los ntawm UBS lub ntsuas hluav taws xob yog raws li hauv qab no:
[Address 00][Function Code 03][Start Address 00 0C][Read Length 00 02][CRC Checksum 05 D9]
Qhov no zoo ib yam li hais tias: "Tag nrho cov meters, thov nyeem cov ntaub ntawv los ntawm kev sau npe 000C, pib nrog rau npe 1."
Tom qab tau txais cov lus, meter #1 yuav teb nrog:
[Address 01][Function Code 03][Data Length 04][Data 00 00 00 00][CRC Checksum FA 33]
Qhov no txhais tau hais tias: "Meter #1 teb: Tag nrho cov txiaj ntsig zoo zog cov ntaub ntawv tus nqi nyeem yog 00 00 00 00 (hexadecimal)" (Ceeb toom: Qhov ntsuas no # 1 yog qhov ntsuas tshiab, tsis siv). Cov duab hauv qab no yog kev sim ua qauv qhia:
Phau ntawv "Cov ntaub ntawv" hauv ib lub ntsuas hluav taws xob: Sau npe piav qhia
Hauv Modbus RTU raws tu qauv, tag nrho cov ntaub ntawv los ntawm lub ntsuas hluav taws xob tau muab tso rau hauv "spreadsheet"-cov ntawv sau npe. Cov ntawv sau npe feem ntau muab faib ua plaub hom:
| Sau npe hom | Nyeem/Sau Tso Cai | Function Codes | Cov Ntsiab Lus Khaws Cia |
|---|---|---|---|
| Coil Sau npe | Nyeem/Sau | 01, 05 | Relay xwm txheej, hloov tswj |
| Discrete Input Register | Nyeem- nkaus xwb | 02 | Digital input (piv txwv li, tswb signals) |
| Sau npe nkag | Nyeem- nkaus xwb | 04 | Tiag -cov ntaub ntawv ntsuas lub sijhawm (voltage, tam sim no, thiab lwm yam) |
| Tuav Sau Npe | Nyeem/Sau | 03, 06 | Cov khoom siv tsis muaj zog, cov khoom siv zog, thiab lwm yam. |
Hauv kev siv hluav taws xob ntsuas hluav taws xob, feem ntau cov ntawv sau npe yog:
Sau npe nkag
(Function Code 04H): Khaws cov ntaub ntawv tiag tiag -lub sijhawm ntsuas xws li voltage, tam sim no, thiab lub zog.
Tuav Sau Npe
(Function Code 03H): Khw muag khoom siv hluav taws xob, khoom siv tsis tau, thiab lwm yam.
UBS Energy Meter Modbus Sau npe Cov Ntaub Ntawv Chaw Nyob
Modbus raws tu qauv chaw nyob yog 0x00. Yog xav paub ntxiv Modbus raws tu qauv sau npe chaw nyob cov ntaub ntawv rau UBS zog ntsuas, thov mus saib cov lus hauv qab no:
| Sau npe (Hex) | Lub npe hloov pauv | Tus cwj pwm (Unit / R / W) | Hom ntaub ntawv | Suav | Lus hais |
|---|---|---|---|---|---|
| 0x0000 | DC voltage | Unit: V, R/W: RO | S16 | 1 | Ntau yam: -9999 ~ 9999; Nyeem=Tus Nqi Zoo × 10^(Decimal Point) |
| 0x0001 | Voltage Decimal Point | Chav tsev: Tsis muaj, R / W: RO | U16 | 1 | Tus nqi ruaj khov: 0 |
| 0x0002 | DC Tus nqi tam sim no | Unit: A, R/W: RO | S16 | 1 | Ntau yam: -9999 ~ 9999 |
| 0x0003 | Tam sim no Decimal Point | Chav tsev: Tsis muaj, R / W: RO | U16 | 1 | Tus nqi ruaj khov: 1 |
| 0x0008 | Tus nqi fais fab | Unit: kW, R/W: RO | S16 | 1 | Ntau yam: -9999 ~ 9999 |
| 0x0009 | Fais fab Decimal Point | Chav tsev: Tsis muaj, R / W: RO | U16 | 1 | Tus nqi ruaj khov: 1 |
| 0x000C | Total Forward Active Zog | Unit: 0.001kWh, R/W: RO | U32 | 2 | High byte thawj, tsawg byte kawg; Piv txwv li: Yog cov ntaub ntawv nyeem=5000, decimal point=2 → Tus nqi tiag tiag=5000 × 10^(2-3)=500.0 |
| 0x203C | Channel 1 Voltage | Chav tsev: 0.0001V, R / W: RO | I32 | 2 | High byte ua ntej, tsawg byte kawg |
| 0x203E | Channel 2 Voltage | Chav tsev: 0.0001V, R / W: RO | I32 | 2 | Ib txwm 0 |
| 0x2040 | Channel 1 Tam sim no | Chav tsev: 0.0001A, R / W: RO | I32 | 2 | High byte ua ntej, tsawg byte kawg |
| 0x2042 | Channel 2 Tam sim no | Chav tsev: 0.0001A, R / W: RO | I32 | 2 | Ib txwm 0 |
| 0x2044 | Channel 1 Lub zog | Chav tsev: 0.0001kW, R / W: RO | I32 | 2 | High byte ua ntej, tsawg byte kawg |
| 0x2046 | Channel 2 Lub zog | Chav tsev: 0.0001kW, R / W: RO | I32 | 2 | Ib txwm 0 |
| 0x9A00 | Forward Active Total Energy | Unit: kWh, R/W: RO | ntab | 2 | |
| 0xA001/0x8900 | Ntaus Chaw Nyob | Unit: Tsis muaj, R/W: RW | U16 | 1 | Loj: 0 ~ 247 |
Ua qauv qhia nyeem ntawv UBS Zog Meter Cov Lus
Siv lub UBS lub zog ntsuas lub tshuab computer software, nyeem cov ntaub ntawv hauv qab no los ntawm DJZ1226 DC ntse lub zog ntsuas: tag nrho lub zog zoo, qhov hluav taws xob, tam sim no, lub zog, thiab qhov chaw nyob 'meter'.
Raws li pom nyob rau hauv daim duab saum toj no, cov ncauj lus kom ntxaws cov ntsiab lus xa thiab tau txais los ntawm tus tswv tsev computer yog raws li nram no:
13:25:30.229 Total positive active zog(000C0002) ...
13:25:30.256 ▼Xa:00 03 00 0C 00 02 05 D9
13:25:30.344 ▲Tau:01 03 04 00 00 00 00 FA 33
13: 25: 30.359 DC voltage (0000002) ...
13:25:30.424 ▼ Xa: 00 03 00 00 00 02 C5 DA
13:25:30.428 ▲ Txais:01 03 04 00 17 00 03 0A 36
13:25:30.494 DC tam sim no (00020002) ...
13:25:30.522 ▼Xa:00 03 00 02 00 02 64 1A
13:25:30.610 ▲Receive:01 03 04 00 30 00 02 7B FD
13:25:30.621 Hwj chim(00080002) ...
13:25:30.682 ▼Xa:00 03 00 08 00 02 44 18
13:25:30.690 ▲ Txais:01 03 04 00 01 00 02 2A 32
13:25:30.702 Kev Sib Txuas Lus 2(A0010001) ...
13:25:30.779 ▼Xa:00 03 A0 01 00 01 F6 1B
13:25:30.783 ▲ Txais:01 03 02 00 01 79 84
13:25:30.795 Xaus cov ntaub ntawv nyeem.
Tej teeb meem thiab kev daws teeb meem
Txawm hais tias Modbus RTU raws tu qauv yog qhov yooj yim, ntau yam teeb meem tseem tuaj yeem tshwm sim hauv kev siv tswv yim. Cov hauv qab no yog ib qho kev ua txhaum thiab kev daws teeb meem hauv kev sib txuas lus hluav taws xob meter:
Tsis muaj kev sib txuas lus teb
● Tshawb xyuas kev sib txuas ntawm lub cev:
▪ Puas yog RS-485 cov kab hluav taws xob muaj tseeb (A/B kab rov qab)?
▪ Puas yog cov terminating resistors sib phim (feem ntau, txuas 120Ω resistors ntawm txhua qhov kawg ntawm lub npav)?
▪ Puas yog qhov kev sib txuas lus deb tshaj qhov txwv (RS-485 theoretically tuaj yeem ncav cuag 1200 meters, tab sis qhov kev ncua deb yog cuam tshuam los ntawm ib puag ncig).
● Txheeb xyuas Parameter Chaw:
▪ Puas yog baud tus nqi, cov ntaub ntawv me me, nres cov khoom, thiab cov kev sib raug zoo sib xws nrog lub ntsuas hluav taws xob?
▪ Puas yog qhov chaw nyob ntawm lub cuab yeej tau teeb tsa raug (tsis muaj chaw nyob dua)?
Kev sib txuas lus tsis sib xws
● Tshawb xyuas kab cuam tshuam:
▪ Siv cov twisted -pair shielded cable thiab xyuas kom meej tias cov ntaub thaiv npog yog grounded ntawm ib kawg.
▪ Tsis txhob khiav cov kab txuas mus rau siab -voltage cables.
● Kev Ntsuas Tus Kheej Cov Khoom Siv:
▪ Txuas txhua lub ntsuas hluav taws xob ib leeg los kho cov khoom siv tsis raug.
▪ Siv UBS Electronics 'tus tswv lub khoos phis tawj software (xws li AMS) los sib txuas lus ncaj qha nrog lub ntsuas hluav taws xob thiab txheeb xyuas qhov teeb meem.
Cov ntaub ntawv yuam kev
● Txheeb xyuas CRC Check:
▪ Tshawb xyuas seb CRC cov lej xa tuaj thiab tau txais puas zoo ib yam.
▪ Paub meej cov ntaub ntawv byte xaj (Modbus RTU feem ntau yog me ntsis -endian).
● Tshawb xyuas Daim Ntawv Qhia Npe:
▪ Paub meej tias cov chaw nyob sau npe siv raws li daim ntawv teev hluav taws xob hauv phau ntawv qhia.
▪ Nco ntsoov qhov chaw nyob sau npe offset.
Yog tias koj xav siv UBS host computer software (Modbus RTU raws tu qauv) uas tau hais hauv tsab xov xwm no, thov hu rau tus neeg saib xyuas koj qhov kev txiav txim ntawm UBS hluav taws xob ntsuas hluav taws xob thiab tau txais ntau ntxiv tom qab- muag kev txhawb nqa.