国产精品久久久久久久久,四季AV一区二区夜夜嗨,日韩精品无码中文字幕电影,www.五月婷婷.com

1794-CE3現(xiàn)貨 in stock! 歡迎來(lái)電咨詢~?。?

分散控制系統(tǒng)(DCS)已在大型火力發(fā)電廠廣泛應(yīng)用，并取得諸多經(jīng)驗(yàn);對(duì)于中小型的企業(yè)自備火電廠或區(qū)域熱電廠，DCS系統(tǒng)的應(yīng)用正在逐步推廣，但其設(shè)計(jì)、施工及維護(hù)經(jīng)驗(yàn) 尚有欠缺，需要不斷摸索和總結(jié)。
　　其DCS系統(tǒng)面臨的重要問(wèn)題之一就是如何有效地抑制干擾，提高控制系統(tǒng)的安全性、穩(wěn)定性與可靠性，由于技術(shù)儲(chǔ) 備不夠完善和人員運(yùn)行經(jīng)驗(yàn)欠缺，中小型火電廠更應(yīng)重視此 點(diǎn)。電源穩(wěn)定供應(yīng)、信號(hào)正確分類及電纜合理敷設(shè)、接地有效 實(shí)施作為抑制干擾、提高系統(tǒng)可靠性的有效方法，值得廣泛探討與研究。
　　通過(guò)分析中小型火發(fā)廠DCS系統(tǒng)對(duì)電源、信號(hào)、接地的抗干擾要求，結(jié)合工程經(jīng)驗(yàn)，闡述了這三方面的抗干擾設(shè)計(jì)方 案，提出了施工及維護(hù)中的一些注意事項(xiàng)，供項(xiàng)目設(shè)計(jì)、施工 以及維護(hù)參考，以便實(shí)現(xiàn)DCS的有效投入，保證電廠安全穩(wěn) 定運(yùn)行。
　　2 DCS系統(tǒng)抗干擾要求
　　為提高電廠DCS系統(tǒng)的測(cè)量水平和控制精度，保證控制 系統(tǒng)的安全、穩(wěn)定、可靠運(yùn)行，熱控專業(yè)在設(shè)計(jì)、施工、維護(hù)階段必須合理考慮DCS系統(tǒng)在電源、信號(hào)、接地方面的抗干擾要求。
　　2.1 電源要求
　　電源安全性是任何供電系統(tǒng)必須滿足的最基本條件。首先在前期設(shè)計(jì)中在沒(méi)選擇電源和開(kāi)關(guān)型號(hào)時(shí)，充分考慮所有設(shè)備最大工作電流，并留出足夠余量，方便日后增加設(shè)備。其次在選擇電源線路時(shí)，不僅要求根據(jù)電流容量選擇合適線徑，而 且要求有足夠機(jī)械強(qiáng)度，具有防腐性，并且能夠阻燃。
　　電源可靠性和連續(xù)性是DCS穩(wěn)定運(yùn)行的前提。DCS供電 系統(tǒng)除給DCS供電外，不應(yīng)再接入其他系統(tǒng)和設(shè)備，如果無(wú) 法實(shí)現(xiàn)獨(dú)立電源，那么可以通過(guò)加裝電源隔離裝置的方法(常 用UPS不間斷電源)來(lái)實(shí)現(xiàn)。供電電源應(yīng)有兩路電源供電，一路應(yīng)采用交流不問(wèn)斷電源(UPS)，另一路來(lái)自廠用低壓工 作段電源。兩路電源宜設(shè)自動(dòng)電源切投裝置，切投時(shí)間應(yīng)確保 不影響控制系統(tǒng)的運(yùn)行。任何一路電源失去或故障不應(yīng)引起控 制系統(tǒng)任何部分的故障、數(shù)據(jù)丟失或異常動(dòng)作;任何一路電源 失去都應(yīng)在控制系統(tǒng)獲得報(bào)警。
　　2.2信號(hào)要求
　　DCS的輸入、輸出信號(hào)線是干擾信號(hào)進(jìn)入DCS的途徑之一，一般來(lái)說(shuō)信號(hào)越弱受干擾的影響越大。首先應(yīng)對(duì)信號(hào)分類 如下：
　?、買(mǎi)類信號(hào)：熱電阻信號(hào)、熱電偶信號(hào)、毫伏信號(hào)、應(yīng)變信號(hào)等低電平信號(hào)。
　?、冖蝾愋盘?hào)：0～5 V、1～5 V、4～20 mA、0～10 mA模 擬量輸入信號(hào);4～20 mA、0～10 mA模擬量輸出信號(hào);電平型/觸點(diǎn)型開(kāi)關(guān)量輸入信號(hào);脈沖量輸入信號(hào);24VDC小于50 mA的阻性負(fù)載開(kāi)關(guān)量輸出信號(hào)。
　?、邰箢愋盘?hào)：24V～48VDC感性負(fù)載或電流大于50 mA 的阻性負(fù)載的開(kāi)關(guān)量輸出信號(hào)。
　?、堍纛愋盘?hào)：110VAC或220VAC開(kāi)關(guān)量輸出信號(hào)，此類信號(hào)的饋線可視作電源線處理布線的問(wèn)題。
　　其中，I類信號(hào)很容易被干擾，Ⅱ類信號(hào)容易被干擾，而Ⅲ和Ⅳ類信號(hào)在開(kāi)關(guān)動(dòng)作瞬間會(huì)成為強(qiáng)烈的干擾源，通過(guò)空間環(huán)境干擾附近的信號(hào)線。
　　為了有效減小各個(gè)信號(hào)之間的干擾，不同類型的信號(hào)電纜與DCS相連時(shí)，信號(hào)電纜的設(shè)計(jì)和布置應(yīng)滿足以下原則：
　　①對(duì)于I類信號(hào)電纜，最好采用屏蔽雙絞電纜。
　②對(duì)于Ⅱ類信號(hào)，盡可能采用屏蔽電纜，其中Ⅱ類信號(hào)中用于控制、聯(lián)鎖的模入/模出信號(hào)、開(kāi)入信號(hào)，必須采用屏蔽 電纜。
　?、蹖?duì)于Ⅳ類信號(hào)嚴(yán)禁與I、Ⅱ類信號(hào)捆在一起走線，應(yīng)作為220 V電源線處理，與電源電纜一起走線，有條件時(shí)建議采 用屏蔽雙絞電纜。
　?、軐?duì)于Ⅲ類信號(hào)，允許與220 V電源線一起走線(即與Ⅳ類信號(hào)相同)，也可以與I、Ⅱ類信號(hào)一起走線。但在后者情 況下Ⅲ類信號(hào)必須采用屏蔽電纜，最好為屏蔽雙絞電纜，且與 I、Ⅱ類信號(hào)電纜相距15cm以上。
　?、萜帘坞娎|的屏蔽層必須只有一點(diǎn)接地，并且要接地 良好。
　　⑥絕對(duì)禁止大功率的開(kāi)關(guān)量輸出信號(hào)線、電源線、動(dòng)力線等電纜與直接進(jìn)入DCS系統(tǒng)的I、Ⅱ類信號(hào)電纜并行捆綁。
　?、呓^對(duì)禁止采用一根多芯電纜中的部份芯線用于傳輸I類 或Ⅱ類的信號(hào)，另外部分芯線用于傳輸Ⅲ類或Ⅳ類信號(hào)。
　?、鄧?yán)禁同一信號(hào)的幾芯線分布在不同的幾條電纜中(如三線制的熱電阻)。

ADVANTECH PCL-849 PCL-849A RS-232 Comm Card

ALLEN-BRADLEY 800MB-CPB16SA CONTACT PUSH BUTTON AB

ABB BAILEY SYMPHONY CONTROLS DIGITAL IMASI23 ANALOG INPUT SLAVE MODULE 88142

ACCURAY 086155-001 086154-001 SCANNER VME MODULE CONTROLLER CONTROL B208804

Adimec MX12P camera MX 12P MX 12 P MX12P/8X40 ISS:1.1

6SE3126-8CJ40 6SE-3126-8CJ40 MIDI MASTER MD1850/2

75 HP ELECTRIC MOTOR 1800 365TP VHS FOR IRRIGATION Replacement For US & GE

SIEMENS 6SE3-224-2DJ40 NSFP 6SE32242DJ40

ALLEN BRADLEY 1394C-SJT10-D USPP 1394CSJT10D

GETTYS 110-0134 NSFP 1100134

GE FANUC 44A398722-G03 USPP 44A398722G03

SIEMENS 6SC9111-2AF2 USPP 6SC91112AF2

SICK OPTIC ELECTRONIC PLS101-112 USPP PLS101112

ACCURAY 725782 USPP 725782

Siemens 6ES5 900-7AA11 6ES59007AA11

Siemens S5 6ES5 385-8MB11 High Speed Counter Module

SIEMENS 6ES5-464-8ME11/6ES5464-8ME11 ANALOG INPUT MODULE NIB

Siemens 6ES5 430-4UA12/6ES54304UA12 FACTORY SEALED

Siemens S5 Power Supply Module S5-110A 6ES5 930-7AA21 WARRANTY

Siemens CUVC 6ES7 090-0XX84-0AB0

SFP-10G-LR LONGLINE 10GBASE-LR SFP MODULE FOR CISCO

Square D 8030 RRK-200

Siemens 6ES5 318-8MA12 Simatic S5 Interface Module

WE SHIP SAME CISCO WS-C3750X-24S-E SWITCH 1 YR 3750X-24S

Siemens 6GK7 243-2AX01-0XA0

SIEMENS TP177B 6AV6 642-0BA01-1AX1 Touch Glass + Protective film

Schneider Modicon AS-BDEP-210 Discrete Input NIB

Schneider Modicon ASBDEP210 8 Pt 120VAC Input Module AS-BDEP-210 Electric

Schneider Modicon AS-B806-032 NSFP ASB806032

Schneider Modicon Panelmate plus MM-PMC3-100 110/230 V As Is Parts Or Repair

Schneider Modicon AS-MBPL-001 USPP ASMBPL001

Schneider Modicon AS-B885-002 ASB885002 Basic Module

Schneider/Telemecanique PLC Output Module TSXASZ401

SIEMENS 6ES7 321-1FH00-0AA0 INPUT MODULE 6ES73211FH000AA0

SANS DIGITAL MR4UT MobileRaid 4-bay hardware RAID

Siemens HMI 6AV6 641-0AA11-0AX0 NIB 6AV66410AA110AX0

SIEMENS Sinumerik 802S 802C Mechanical Keypad

SIEMENS 6ES5 521-8MA21 CP521 SI COMMUNICATION MODULE RE

SIEMENS 6SN1145-1AA01-0AA2 (6SN11451AA010AA2) NIB

SIEMENS 6SN1118-0AA11-0AA0 6SN1 118-0AA11-0AA0 SIMODRIVE 611-A Control Unit QTY

SIEMENS 6FC5130-0CA01-0AA0 USPP 6FC51300CA010AA0

AllenBradleyPanelview2711-B6C2X/A2711B6C2X

ALLEN BRADLEY X-66799 USPP X66799

ABB DRIVE WITH BYPASS ACH401600632

Adept X-Y-Z Slide Robot Module with Controller and Pendant

(8435) Allen Bradley Magnetic Contactor 1100-BOD93 1500V SEE PICS

INDRAMAT TDM3.2-020-300-W0 NSPP TDM32020300W0

WESTRONICS INC 3000-111-010-031-012-0-0 USPP 300011101003101

FANUC A13B-0153-C001 USPP A13B0153C001

ELEKTROR HRD65/7/EL NSFP HRD657EL

RELIANCE ELECTRIC 86466-25 USPP 8646625

OMRON C500-CT041 USPP C500CT041

OMRON CV500-SNT31 USPP CV500SNT31

Siemens 6ES5 441-4UA14 6ES54414UA14

Siemens 6ES5-921-3UA12/6ES5921-3UA12 CPU MODULE XLNT

SIEMENS 6ES5-400-7AA13 PLC

Siemens 6ES5 440-8MA21 DIGITAL OUTPUT MODULE

Siemens S5 6ES5 420-4UA13 6ES54204UA13 Input Module

Siemens 6SE7090-0XX84-0FF5 DP Communication Card

Siemens 6ES7 331-7SF00-0AB0 SIMATIC SM331 ANALOG SEALED

Sola sld-12-3015-05

MOLEX MANAGEMENT INTERFACES MODULE WARRANTY

WS-X4648-RJ45-E CISCO Catalyst 4500E Series Line Card Switch 48 ports

Siemens 6ES7 421-1BL00-0AA0 6ES7421-1BL00-0AA0 NIB

SIEMENS RWD44U Controller

Reliance 0-57408-B

Schneider Modicon like hc SCIENCE AS A CONTACT SPORT Save Earth's Climate Stephen H

Schneider Modicon AS-B258-001 USPP ASB258001

Schneider Modicon AS-P964-000 Data Access Panel

Schneider Modicon AS-B838-032 24 VDC 32-Point Output Module

Schneider Modicon AS-B802-008/ASB802008

Modicon MM-PMA2-300 PanelMate Plus P/N 92-00808-02

Siemens Simatic 505-4116 Low VDC Input Module

SIEMENS 6ES5-305-7LB11 NSPP 6ES53057LB11

SIEMENS S5 6ES5 470-7LC12 Analog Output Module

SIEMENS 6DD2920-0AC0 LIGHT INTERFACE MODULE

SIEMENS SINUMERIK 840C/840CE MMC CPU 6FC5110-0DB03-0AA4 NIB

SIEMENS 6SN1112-1AC01-0AA1 SIMODRIVE 6SN11121AC010AA1

SIEMENS SIMODRIVE 611 SERVO DRIVE 6SN1145-1BA01-0DAI IN BOX

SIEMENS 6FC9348-5XC FNFP 6FC93485XC

Advantech Motherboard PCA-6104 NIB

ALLEN-BRADLEY 1771-OD16 120V AC Isolated Output Module

ABB ACS60101205000B1200000

ADDIDATA PA8000 NSPP PA8000

6ES7614-1AH00-0AB3 6ES7614-1AH03-0AB3 Brand , Factory Sealed,

90pcs LSI Agere 2650B Broadband Photodiode For CATV, Video Transportation, EDFA

SQUARE D PHF2036 NSPP PHF2036

CONTROL TECHNIQUES SP4401 USPP SP4401

BONO ENERGIA F3330-984333002 NSPP F3330984333002

NACHI AUXL112A USPP AUXL112A

MEASUREX 08562100 USPP 08562100

FANUC A06B-6102-H206 USPP A06B6102H206

Siemens 6ES5 185-3UA00 6ES51853UA00

Siemens 6ES5-465-7LA13 Input Module Analog NIB

SIEMENS 6ES5-095-8MA02 6ES5095-8MA02 CPU

SIEMENS S5 6ES5-530-7LA12 MODULE

Siemens 5 Part 6ES5 422-8MA11

SIEMENS 6ES7413-1XG02-0AB0

Siemens Stepdrive C 6FC5548-0AA00-0AA0

Siemens 6ES5376-1AA31

Inb 683760-004 Stack Interface Module for 500 Series

YOSHIMURA FOR POLARIS XP900RZR 2011

Siemens 6ES5921-3UA12 IN BOX

Siemens MP277-8 6AV6 643-0CB01-1AX1 Protective Film

Oriental Motor E3769-122 / E3570-424

Schneider Modicon AS-B885-111/ASB885111 Motion Module CLEANOFFERS ACCEPTED

Schneider Modicon AS-516P-002 USPP AS516P002

Schneider Modicon AS-L206-011 USPP ASL206011

Schneider Modicon AS-8533-003 NSFP AS8533003

Schneider Modicon / Remote Processor AS-J890-001

Schneider Modicon AS-B824-016 Tru High Output Module

Siemens UD5N Input Module

Schneider/Modicon 140CPS11420 CPS11420

Siemens Sinumerik 840 1P-6FC5103-0AD13-0AA0 1P6FC51030AD130AA0 _ 570-524-9101-00

SIEMENS 500-5019 OUTPUT MODULE 5005019

SIEMENS SINUMERIK 810D/840DPCU20 6FC5210-0DF00-1AA1

Clear-Com Assy 710310 Com-2 Communications Module

SIEMENS SIMODRIVE 6SN1145-1BB00-0EA1

SIEMENS SIMODRIVE 6SN1145-1AA01-0AA1SINUMETIK 840D NCU-BOX 6FC52476FC53562AA

Advantech MIC-3809 A1 02-1

ALLEN-BRADLEY 2755-DD4A DUAL-HEADED BAR CODE DECODER SURPLUS

ABB 3HAB5760-1 IRB6400 M96, M97, M98, M2000 Robot Servo Motor for Axis 2 or 3

ACCURAY 086161-002 USPP 086161002

A100614 Agilent 8960 Series 10 E5515C Wireless Communication Test Set w/ Opt 003

80C02 Tektronix 20GHZ Optical Module

SIEMENS 6ES5-926-3SU11 USPP 6ES59263SU11

ASEA BROWN BOVERI 57171847 USPP 57171847

ALLEN BRADLEY 8000-MDD USPP 8000MDD

LORAIN PRODUCTS 486531001 USPP 486531001

HEWLETT PACKARD TEST & MEASURE 9888A USPP 9888A

ALLEN BRADLEY 1336-B007S-EOD/L3 USPP 1336B007SEODL3

RELIANCE ELECTRIC 0-56313-1 NSFP 0563131

Siemens 6ES5-355-3UA11 USPP 6ES53553UA11

SIEMENS 6ES5 450-8MB11 6ES54508MB11

SIEMENS smatic S5 plc card 6ES5 262-8MA12 CLOSED LOOP Controller

Siemens Output Card 6ES5 441-4UA13 NIB

Siemens 6ES7 277-0AA21-0XA0 6ES7277-0AA21-0XA0 Profibus

SIEMENS OPM2 6SE3290-0XX87-8BF0 OPERATOR INTERFACE

PWR-C49M-1000AC 4900M AC POWER SUPPLY 1000 WATTS

GSI LUMONICS DSPLINK3 MODULEOPTRA 1-1207-4SYSTEM INTERFACE BOARD 229.055.00

Tripp Lite B054001USB USB Server Interface Module B054-001-USB

Siemens 6AG1 223-1PL22-2XB0 6AG1223-1PL22-2XB0 FreeShip

Siemens IGBT BSM75GB120DN1E3204

Modicon SW-AP5T-MTA

Schneider Modicon Gould AS-B370-001 Register Output ASB370001

Schneider Modicon ASJ470-000 Programming Module AS-J470-000

Schneider Modicon AS-E380-902 MEMORY CARTRIDGE ASE380902

Schneider Modicon AS-P933-000

Schneider Modicon AS-516P-008

Schneider Modicon module AS-B824-016. 24 VDC INPUT TRUE HIH

Schneider TSX CPP110 TSXCPP110

Schneider Modicon 140-NOE-771-00 140NOE77100

PPT Machine Vision Impact C40 Processor Cables I/O Bd

SIEMENS 6ES5 440-8MA11 DIGITAL OUTPUT MODULE IN BOX

SIEMENS 6FC5247-0AA02-1AA0 6FC52470AA021AA0 Sinumerik

HILSCHER CIF-50-PB COMMUNICATION MODULE INTERFACE CIF50PB

SIEMENS SIMODRIVE 6SN1146-1AB00-0BA1SINUMETIK 840D NCU-BOX 6FC5247-0AA00-0AA2#4

SIEMENS SINUMERIK 802D KEY BOARD 6FC5603-0AC13-1AA0

SIEMENS MOORE 123712-386 REPAIR KIT FOR MODEL 74 VALVE POSITIONER 41493

Allen-Bradley Panelview 1200 Operator Interface 2711-TC1X

5800: 430-450Mhz Total Surveying Solution 90D

ABB Upper arm cable w/cust. conn. part# 3HAA0001-YH

A06B-0153-B175#7076 FANUC SERVO MOTORS REMANUFACTURED

7451 IC 14 Pin Dip- Dual 2-Wide 2-IN AND/OR/Invert Gate

RELIANCE ELECTRIC 40V2060 NSFP 40V2060

ALLEN BRADLEY 1785-L80E/E USPP 1785L80EE

ALLEN BRADLEY 150-B35NBDA-J1 USPP 150B35NBDAJ1

GETTYS 110-0221 USPP 1100221

TRICONEX 4107 USPP 4107

TECH MOTIVE TOOL 48S440-31023 USPP 48S44031023

FOXBORO P0400DA-0K USPP P0400DA0K

Siemens 6ES5-103-8MA03/6ES5103-8MA03 CPU MODULE 24VDC XLNT

SIEMENS 6ES5 373-1AA61 -- 6ES53731AA61

SIEMENS 6ES5-942-7UB11/6ES5942-7UB11 CPU MODULE XLNT

Siemens 6ES5 755-2CA11 NSFP 6ES57552CA11

Siemens 6ES5 312-5CA11 6ES5312 6ES53125CA11

Siemens LOGO! DM8 230R 6ED1 055-1FB00-0BA1 Module NIB

Rev 1.1 SuperMicro H8DAE-2 Bulk Pack MB Support Dual Core CPU

Texas Instruments 2587678-8008

Spirent Adtech 400308A AX/4000 ATM DS1 Interface

VMware 2U Server 4x Six-Core Istanbul 2.6GHz 128GB RAM

Siemens C79458-L2197-A1

Modicon AS-T984-101

Schneider Modicon AUTOMATION DEP 218/AS-BDEP-218

Schneider Modicon AS-8535-000 AS8535000 High Density Connector

Schneider Modicon AS-BADU-205 ASBADU205 Analog Input LNC

Schneider Modicon AS-B805-016 115VAC Input Module ASB805016

Schneider Modicon PLC PC-0984-381 AS-9584-000

Schneider Modicon AS-S482-500 S-Pack AS-IS

SCHNEIDER 6728-042.270385 DAP216 OUTPUT MODULE XLNT

Sharp JW-234N Input Module 32POINT 12/24VDC 4.5MA High Speed

RELIANCE 57C416/0-57416 REMOTE I/O COMM MODULE NIB

Siemens 6ES7 322-5GH00-0AB0 OUTPUT MODULE 16DO 24-48VU

SIEMENS SINUMERIK 6FC5247-0AA16-0AA1 6FC52470AA160AA1 NIB

NUMATICS 239-1514 DEVICENET COMMUNICATION MODULE

SIEMENS SIMODRIVE 611 6SN1118-0DJ21-0AA1

SIEMENS SINUMERIK OP012 6FC5203-0AF02-0AAL Membrane Keypad

SIEMENS HANNIFIN 6F-C6L-1-BN-B USPP 6FC6L1BNB

AllenBradley1771-OBD/BOutputModule

ALLEN BRADLEY SLC500 BASIC MODULE 1746-BAS C 1746BAS C

ABB PLC MODULE PM581-ETH MODULES

York Liquid Chiller LCH10W-45B _ LCH10W45B _ LCH1OW-45B _ LCH1OW45B

[2 UNITS] Keithley 238 High-Current Source-Measure Unit - Functionally Tested

MODICON AS-584L-211 USPP AS584L211

ALLEN BRADLEY 1395-A63-C1-P51-X1 USPP 1395A63C1P51X1

GIDDINGS & LEWIS M.1301.5649 NSFP M13015649

GE FANUC IC3600SHPB1 USPP IC3600SHPB1

SIEMENS 6SE3-221-5DC40 NSFP 6SE32215DC40

SIEMENS 6AV3-520-1DK00 USPP 6AV35201DK00

ALLEN BRADLEY 1391-DES15-DI-AQB USPP 1391DES15DIAQB

Siemens 6ES5 922-3UA11 6ES59223UA11

Siemens S5 6ES5 955-3LF11 6ES59553LF11 Power Supply

SIEMENS 6ES5-482-3BA11 USPP 6ES54823BA11

Siemens 6ES5 430-8MB11/6ES5430-8MB11 INPUT MODULE XLNT

Siemens S5 Timer Module 6ES5 380-8MA11

Siemens DCS Module 6DS1702-8AA in Box, seal opened,

SCHWEITZER 250603414X SEL-2506 REMOTE I/O MODULE NIB

Square D 8803 P00CO2C

Siemens 6ES5310-3AB11 Interface Module 60 DAY WARRANTY FREE

WE SHIP SAME CISCO WS-C3750G-24PS-S CATALYST 3750G-24PS SWICTH 1 YR WARRA

Siemens 6GK7243-2AX01-0XA0 6GK72432AX010XA0

Siemens TP178 6AV6 640-0DA11-0AX0 Touchscreen Glass

Schneider Modicon TSX08CD12R8AS Telemecanique TSX NESA

Schneider Modicon AS-BDAU-204 SEALED BOX Compact Analog OUT ASBDAU204