yokogawa AMM12C橫河
yokogawa AMM12C橫河
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影響PLC控制系統(tǒng)的干擾源與一般影響工業(yè)控制設(shè)備的干擾源一樣，大都產(chǎn)生在電流或電壓劇烈變化的部位，這些電荷劇烈移動(dòng)的部位就是噪聲源，即干擾源。干擾類型通常按干擾產(chǎn)生的原因、噪聲干擾模式和噪聲的波形性質(zhì)的不同劃分。
其中按噪聲產(chǎn)生的原因不同，分為放電噪聲、浪涌噪聲、高頻振蕩噪聲等;
按噪聲的波形、性質(zhì)不同，分為持續(xù)噪聲、偶發(fā)噪聲等;
按噪聲干擾模式不同，分為共模干擾和差模干擾。共模干擾和差模干擾是一種比較常用的分類方法。
共模干擾是信號(hào)對(duì)地的電位差，主要由電網(wǎng)串入、地電位差及空間電磁輻射在信號(hào)線上感應(yīng)的共態(tài)(同方向)電壓迭加所形成。共模電壓通過(guò)不對(duì)稱電路 可轉(zhuǎn)換成差模電壓，鐘影響測(cè)控信號(hào)，造成元器件損壞(這就是一些系統(tǒng)I/O模件損壞率較高的主要原因)，這種共模干擾可為直流、亦可為交流。
從PLC外部考慮：
使用隔離的PC/PPI電纜，盡量不用廉價(jià)的非隔離電纜(特別是在工業(yè)現(xiàn)場(chǎng))。西門子公司早期出產(chǎn)的PC/PPI電纜(6ES7901-3BF00-0A0)是不隔離的，現(xiàn)在也改成隔離的電纜了!
PLC的RS485口聯(lián)網(wǎng)時(shí)采用隔離的總線連接器.
與PLC聯(lián)網(wǎng)的第三方設(shè)備，如變頻器、觸摸屏等的RS485口均使用RS485隔離器BH-485G進(jìn)行隔離，這樣各RS485節(jié)點(diǎn)之間就無(wú)“電"的，也無(wú)地線環(huán)流產(chǎn)生，即使某個(gè)節(jié)點(diǎn)損壞也不會(huì)連帶其它節(jié)點(diǎn)損壞。
MRC 306SG-H201 Ball Bearing 306SGH201 New
McGill Cam Follower Camfollower Bearing CFE-11/16-SB CFE 11/16 SB CFE11/16SB
NEW NTN BEARING 6007 ZZC3/5C 6007ZZC35C
SEAL MASTER BLACK BROS 2310 ROD END BEARING HOUSING
Hyster OEM Tapered Bearing Outter Cup/Race 0299267 NEW
IKO Needle Bearing BR-445628 BR445628 New
NEW NSK 6011DU RUBBER SEALED BALL BEARING 6011 DU
NEW SKF BEARING 5202 HC 5202HC
NEW IJK BEARING KP8AX
PTI Pillow Block Bearing RAK45 RAK 45 HC209-28 NEW
TRW MRC 100KSZZ (0112) BEARING NEW
New INA NKI 10/20 Roller Bearing NKI10/20
NEW FAFNIR BEARING WS3PP2
NEW NSK BALL BEARING R14V
Consolidated Steyr Roller Bearing 1209K 1209 K NEW
New NSK Ball Bearing 520 TNGC3 520TNGC3
BBC BEARINGS BEARING H40L NEW
New NXZ ZXN Bearing 60308-80308 6030880308
Bower Tapered Roller Bearing LMZ9749 New
SKF Tapered Roller Bearing 31597 K-31597 New
NEW NTN SEALED BALL BEARING 63203Z
NEW INA/ANDREWS THRUST BEARING GT9
SKF Single Groove Ball Bearing 6216 New
NEW NO NAME BEARING 77R8
RBC INNER RACE BEARING IR-7173 IR7173 NIB
SKF Tapered Roller Bearing 598A New
No Name Thrust Bearing NTA-1220 NTA1220 New
RBC NEEDLE BEARING SJ 7355 SS SJ7355SS NIB
NEW NSK BEARING R16V 267 R16V267
NEW Browning Roller Bearing LS-120S LS120S
NEW MB MANUFACTURING INSERT BEARING MSLN12 1104
NEW NO NAME THRUST BEARING 4X 1410-20 4X141020
NEW MRC TRW BEARING R16Z ABEC1 R16ZABEC1
Fafnir 2MM214WI CR DUL Super Precision Bearing Set 2MM214WICRDUL New
NEW SKF BEARING S3NPP8 PRC S3NPP8PRC S3NPP8 "LOT OF 2"
SKF Tapered Roller Bearing HMS16449 New
SKF SI12C Rod End Bearing SI 12 C New
New NTN Bearing Units UCC206JD1
IGUS 25 3/4" 332.50.100/100 FLEX TRAC CABLE CARRIER
NEW NICE BEARING 3030-DS 3030
GS Needle Bearing 6310 New
MRC Steel Shielded Ball Bearing R4AFF H501 R4AFFH501 R4AFF+62 R4AFF62 New
SKF Deep Groove Radial Ball Bearing w/ Snap Ring 211N 109P New
NEW FAFNIR SUPER PRECISION BEARING MM311K CR MM311KCR
New NTN Bearing Unit UCC206D1 C206J
CONSOLIDATED ADAPTER SLEEVE H-318 x 3-3/16" H318 HA318 AN18 NIB
CONSOLIDATED STEYR BEARING 6004-2RSNR 60042RSNR F67 8244 F678244 6004 NIB
F.K Bearings Female Rod End Bearing F12SB 3/4" Bore 3/4" Right-Hand New
RS485通信線采用PROFIBUS總線電纜，保證層接到每臺(tái)設(shè)備的外殼并zui后接大地。
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