Cov kab lus tshwj xeeb rau kev sib txuas lus kub kub digital yog qhov tseem ceeb rau kev tswj xyuas qhov kub thiab txias thiab kev ua haujlwm ruaj khov. Kev siv tsis raug cai tuaj yeem yooj yim ua rau muaj teeb meem cuam tshuam, kev sib txuas lus cuam tshuam, thiab txawm tias tus tswj tsis ua haujlwm, cuam tshuam ncaj qha rau cov khoom zoo.
1. Tej yam uas yuav tsum tau muaj rau kev xaiv thiab cable
shielded twisted -pair cables (xws li RVSP) yuav tsum tau siv. 2 × 2 × 0.75mm² lossis 1.0mm²)
A / B teeb liab kab yuav tsum nruj me ntsis twisted kom txo tau electromagnetic induction.
Cov ntaub thaiv npog pom zoo kom yog tooj liab hlau braid lossis txhuas ntawv ci + tooj liab mesh cov qauv sib xyaw.
Tsis txhob khiav mus rau cov kab hluav taws xob.
Tuav qhov deb ntawm Ntau dua lossis sib npaug li 30cm los ntawm AC220V / 380V fais fab kab, kab lub cev muaj zog, thiab cov kab tawm inverter.
Yog tias kev hla tsis tuaj yeem zam tau, hla perpendicularly ntawm 90℃lub kaum sab xis kom txo tau qhov cuam tshuam ntawm kev sib txuas.
Bus Length Control:
Kev sib txuas lus RS-485 raug pom zoo kom tsis pub tshaj 1000 meters. Yog tias dhau qhov no, 485 repeater lossis fiber optic hloov dua siab tshiab yuav tsum tau.
Kev sib txuas lus siab dua tso cai rau qhov ntev dua (piv txwv li, 115.2kbps txhawb 1200 meters, 1Mbps tsuas yog txhawb nqa kaum metres).
Topology: Daisy-chain txuas.
Lub hnub qub thiab T-zoo li tus ceg txuas txuas yog nruj me ntsis txwv tsis pub kom tsis txhob cuam tshuam cov teeb liab. Intermediate nodes yuav tsum tsis txhob arbitrarily branched; tag nrho cov khoom siv yuav tsum tau txuas nrog hauv series ntawm cov kab tseem ceeb. Tswv yim pom zoo: Txhim kho cov chav sib cais rau cov kab sib txuas lus hauv cov tais cable kom cais tawm lub cev siab - cov kab hluav taws xob.
2. Kev Tiv Thaiv thiab Grounding Specifications (Key Anti-Interference Measures)
Tib -Xaiv av ntawm Shielding Layer:
Nws raug nquahu kom siv ib qho - taw tes hauv av ntawm chav tswj sab (PLC/DCS kawg). Nyob rau sab teb (kub khiav tswj qhov kawg), txheej thaiv yuav tsum raug tshem tawm lossis insulated.
Kev sib sau ua ke hauv av ntawm ob qho kawg yog txwv tsis pub tiv thaiv cov dej ntws los ntawm qhov sib txawv hauv av, uas tuaj yeem dhau los ua qhov cuam tshuam.
Grounding Resistance Requirements:
Lub teeb liab grounding kuj yuav tsum tsawg dua los yog sib npaug rau 4Ω kom ntseeg tau tias qhov qis -impedance paug txoj kev.
Nws yuav tsum tsis txhob sib xyaw nrog lub ntiaj teb tiv thaiv (PE) thiab yuav tsum tau txuas nrog nws tus kheej mus rau qhov ntsuas hauv av.
360℃Tag Nrho -Circumference Grounding ntawm Shielding Layer:
Siv cov hlau txuas lossis thaiv cov hlua khi kom ua tiav kev sib cuag ntawm cov kab thaiv kab thaiv txheej thiab cov hlau casing ntawm lub davhlau ya nyob twg thaiv, tsis txhob "pigtail" hom uas tsis yog - puv - kev sib txuas.
Kev siv: Hauv kev ua haujlwm tsis raug, ntau dua 60% ntawm kev sib txuas lus tsis ruaj khov tshwm sim los ntawm kev tiv thaiv tsis zoo.
3. Termination Resistor Setting (Tsev teeb liab kev ncaj ncees)
Ib qho 120Ω terminating resistor yuav tsum tau ntxiv rau ntawm txhua qhov kawg ntawm lub npav.
Qhov chaw teeb tsa: Nruab nrab ntawm ob qhov kev sib txuas lus tshaj plaws (thawj thiab zaum kawg).
Termination resistors yog nruj me ntsis txwv tsis pub txuas mus rau nruab nrab nodes, txwv tsis pub nws yuav ua rau impedance mismatch thiab nce lub teeb liab xav.
Termination Resistor Power Xaiv
Nws raug nquahu kom siv 1/4W lossis 1/2W resistor los xyuas kom meej ntev - lub sijhawm ua haujlwm ntseeg tau.
Ib qho kev tsis ncaj ncees tuaj yeem muab ntxiv yog tias muaj kev cuam tshuam loj heev.
Txuas kab A rau +5V rub- nce (1kΩ), thiab kab B rau GND rub- nqes (1kΩ) los tiv thaiv lub tsheb npav los ntawm ntab thiab ua rau me ntsis yuam kev.
Kev Tshawb Fawb Txog Kev Tshawb Fawb: Siv lub multimeter los ntsuas qhov sib npaug ntawm cov tsheb npav A thiab B. Nws yuav tsum yog kwv yees li 60Ω (ob lub 120Ω resistors nyob rau hauv parallel). Txwv tsis pub, nws qhia tau hais tias qhov kev txiav txim tsis raug.
4. Lwm cov ntsiab lus tseem ceeb
Cable Bending Radius: Tsis pub tsawg dua 6 npaug ntawm txoj kab uas hla sab nraud rau cov hlua tsis muaj armored, thiab tsis pub tsawg dua 12 npaug ntawm txoj kab uas hla ntawm armored cables, los tiv thaiv kev puas tsuaj sab hauv.
Terminal Tightness: Tsis tu ncua xyuas cov kev sib txuas lus terminals kom looseness. Hauv ib puag ncig kev co, lub caij nplooj ntoos hlav- loaded terminals raug pom zoo.
Clear Labeling: Kev sib txuas lus cables yuav tsum tau sau "Digital Communication - Shielded Cable" kom tsis txhob muaj kev hloov pauv.
