易卖工控网(www.ymgk.com)提供”CP451-50”,产品详情:品牌/厂家:Schneider、型号:CP451-50、成色:全新、货期:期货 1天内发货、保修:360天,更多产品详情就上易卖工控网。
品牌:AB 系列:1784系列
AB可编程逻辑控制器PLC(Programmable Logic Controller)简要介绍
★ 热线:0592-2350125 /18050025541(微信同号)★ 业务QQ:2851759116
可编程控制器是60年代末在美国首先出现,当时叫可编程逻辑控制器PLC(Programmable Logic Controller),目的是用来取代继电器,以执行逻辑判断、计时、计数等顺序控制功能。PLC的基本设计思想是把计算机功能完善、灵活、通用等优点和继电器控制系统的简单易懂、操作方便、价格便宜等优点结合起来,控制器的硬件是标准的、通用的。根据实际应用对象,将控制内容编成软件写入控制器的用户程序存储器内。控制器和被控对象连接方便。

随着半导体技术,尤其是微处理器和微型计算机技术的发展,到70年代中期以后,PLC已广泛地使用微处理器作为中央处理器,输入输出模块和外围电路也都采用了中、大规模甚至超大规模的集成电路,这时的PLC已不再是逻辑判断功能,还同时具有数据处理、PID调节和数据通信功能。
可编程控制器是一种数字运算操作的电子系统,专为在工业环境下应用而设计。它采用了可编程序的存储器,用来在其内部存储执行逻辑运算,顺序控制、定时、计算和算术运算等操作的指令,并通过数字式和模拟式的输入输出,控制各种类型的机械或生产过程。PLC是微机技术与传统的继电接触控制技术相结合的产物,它克服了继电接触控制系统中机械触点的接线复杂、可靠性低、功耗高、通用性和灵活性差的缺点,充分利用微处理器的优点。
可编程控制器对用户来说,是一种无触点设备,改变程序即可改变生产工艺,因此可在初步设计阶段选用可编程控制器,在实施阶段再确定工艺过程。另一方面,从制造生产可编程控制器的厂商角度看,在制造阶段不需要根据用户的订货要求专门设计控制器,适合批量生产。由于这些特点,可编程控制器问世以后很快受到工业控制界的欢迎,并得到迅速的发展。目前,可编程控制器已成为工厂自动化的强有力工具,得到了广泛的应用。
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A B PLC的工作的三个基本过程内容PLC采用循环扫描的工作方式,在PLC中用户程序按先后顺序存放,CPU从***条指令开始执行程序,直到遇到结束符后又返回***条,如此周而复始不断循环。PLC的扫描过程分为内部处理、通信操作、程序输入处理、程序执行、程序输出几个阶段。全过程扫描一次所需的时间称为扫描周期。当PLC处于停状态时,只进行内部处理和通信操作服务等内容。在PLC处于运行状态时,从内部处理、通信操作、程序输入、程序执行、程序输出,一直循环扫描工作。

1.输入处理
输入处理也叫输入采样。在此阶段,顺序读入所有输入端子的通端状态,并将读入的信息存入内存中所对应的映象寄存器。在此输入映象寄存器被刷新。接着进入程序执行阶段。在程序执行时,输入映象寄存器与外界隔离,即使输入信号发生变化,其映象寄存器的内容也不会发生变化,只有在下一个扫描周期的输入处理阶段才能被读入信息。
2.程序执行
根据PLC梯形图程序扫描原则,按先左后右先上后下的步序,逐句扫描,执行程序。遇到程序跳转指令,根据跳转条件是否满足来决定程序的跳转地址。从用户程序涉及到输入输出状态时,PLC从输入映象寄存器中读出上一阶段采入的对应输入端子状态,从输出映象寄存器读出对应映象寄存器,根据用户程序进行逻辑运算,存入有关器件寄存器中。对每个器件来说,器件映象寄存器中所寄存的内容,会随着程序执行过程而变化。
3.输出处理
程序执行完毕后,将输出映象寄存器,即器件映象寄存器中的Y寄存器的状态,在输出处理阶段转存到输出锁存器,通过隔离电路,驱动功率放大电路,使输出端子向外界输出控制信号,驱动外部负载。
ROBERTSHAW 1/2 INCH NPT LEVEL-LANCE TRANSMITTER, 900GA312-01 *NEW*
SCHROEDER DIFFERENTIAL PRESSURE SWITCH, MS5-75, LOT OF 2
F.K. BEARING CFL6MZ 6M X M6 2 PIECE METRIC NIB
ITT NEO-DYN 480VAC 15A 500 PSIG ADJUSTABLE PRESSURE SWITCH, 301P1-2C3K *NEW*
ASHCROFT 2-1/2" 160 PSI INDUSTRIAL DURALIFE PLUS GAU
DISC-INSTRUSTME?NT 3/8 IN SHAFT ENCODER UNKNOWN PART NUMBER
APPLETON EXPLOSION PROOF CONDUIT FITTING 3/4" EYF-EYM NNB
FESTO LR-QS-8 FOR TUBE PUN AND PAN 153542 NIB
ASHCROFT 2" 160 PSI 1/4" NPT POLYCARBONATE PRESSURE GAUGE, 20W1005PH-02B *NEW*
BEI 5-24VDC 3/8" SHAFT DIA. ENCODER, XH25D-SS-500-AB?ZC-7272-EM18
PEPPERL & FUCHS LMPB-A-D24 MOMENTARY LIGHTED PUSH BUTTON, NEW IN BAG
RIGID STEEL CLOSE NIPPLE CONDUIT PIPE 3/4"X4" NIB
BRYANT ELECTRIC .73"-.85" RANGE BUS DROP GRIP, BDS73U *NEW*
UFM FLOW MONITORS MH-NSF16GM-8-32?V1.0-M3WR-PC4M-?C-Z86
TPC WIRE & CABLE 3 POLE 3 WIRE MALE RECEPTACLE, 84300 *NEW*
TPC * QUICK CONNECT CORD SET M/F EXT CNLC 4P 2M * 94412 REV. G
BECKMAN 120V 5A TJ-6 TABLE TOP CENTRIFUGE 340508
ASHCROFT 2" DIAL 15 PSI 1/8" NPT PRESSURE GAUGE, 20W1005 H 01B XRG 15# *NEW*
COOPER ARROW HART 600VAC/250VDC 20/60A 3P 4W POWER-LOCK PLUG, 21426S *NEW*
COPPER WIRING DEVICES 250/600V 20A 3POLE 4WIRE POWER LOCK PLUG, *NEW*
TPC WIRE & CABLE 4 POLE 3M FEMALE RECEPTACLE, 94438 *NEW*
ABB I/O REMOTE UNIT CS31 ICSK20F1
MINERALLAC FITS 1 1/2" RIGID/IMC 4 NIB LOT OF 70
NIDEC 12VDC .22A FANS, TA225DC, NEW LOT OF 2
SCIENTIFIC TECHNOLOGY INC. STI SOLID STATE RELAY OUTPUT, OS-1 *NEW*
O-Z GEDNEY 1-1/2" HUB MALLEABLE IRON CONDUIT BODY, C-150 *NEW*
DATAMETRICS 10245LDS8B1A ENCODER
NOSHOK -30IN.HG 1/8" NPT PRESSURE GAUGE, 15-100-30ZVAC/K?PA *NEW*
STEARNS 115VAC 60HZ COIL, 6-3-61159-09
GEMS 3.5-15PSI 5A 7/16"-20SAE MALE 220907 PRESSURE SWITCH,PS11-20-?4MSB-C-H *NEW*
BEI 5VDC 3/8" SHAFT DIA. ENCODER, H25D-SS-125-ABZ?-7406R-LED-EM16
GENERAL ELECTRIC 480VAC 5A ASTAT SOLID STATE STARTER, *LOT OF 2*
ASHCROFT 2-1/2" DIA. 60 PSI 1/4" NPT PRESSURE GAUGE, 436-05
NEWARK ELEMENT 14 CAN MS3106F14S-6P 7425529 NIB
BEI 3/8" SHAFT DIA. ENCODER, H25E-SB-7200-M5?-ABZC-8830-SM18
PRECISION INSTRUMENT CO. 2-1/2" 160 PSI 1/4" NPT PRESSURE GAUGE,102D-254F *NEW*
SPRECHER AND SCHUH CA7-23C-M40
SIEMENS 440V 0.57/0.33A MOTOR, 2CW5-155-0
COOPER CROUSE-HINDS 300V 3A 5P 4M MALE IN-LINE TO FEMALE CABLE, CHDN-EAE-D4*NEW?*
NORGREN 160 PSI 11 BAR 1/4" NPT PRESSURE GAUGE, 18-013-209 *NEW*
EBM * 115V 25/24W FAN * W2S115-AG03-13
SIEMON CAT5 FLAT SINGLE COUPLER, CT-5F-A4-04 *NEW SEALED*
MILLER HV2-61B4B-02.00?-6.000-0100-S22?- NNB
BALLUFF PROXIMITY SENSOR BES 516-327-G-S 4-H, 10-55 V DC 200 mA sn = 15mm
TURCK 250V 4.0A 4PIN LARGE PLUG BODY EXTENSION, WKE 4.4T-0.3-RSE 4.4T/S600 *NEW*
AMPHENOL SIZE 22 8POS 90 DEGREE CIRCULAR CONNECTOR PLUG, MS3108E22-23P *NEW*
DUCTOWIRE 1 SPEED INSERT #PB-1A (LOT OF 3)
WIEGMANN S2120171
LUMBERG 300V 7A3-POLE PARALLEL WIRED MINI STYLE DISTRIBUTION BOX, ZVS6-30
WOODHEAD BRAD CONNECTIVITY 300V 4A 5P 5M M/F CORDSET, 885S30D04M050 *NEW*
LEVITON 125V 15A 2-POLE 3-WIRE LOCKING PLUG, 7567-C *NEW*
OMRON PHOTOELECTRIC SENSOR E2E-X3D1-N 28104 NNB
TRERICE 230°F MAX, 110°C MAX THERMOMETER BX9140347 *NEW*
WEKSLER 3-1/2" STEM 9" SCALE 50/550°F ADJUST ANGLE THERMOMETER A935AF8-AL, NIB
T+H 115V 400W CARTRIDGE HEATERS, TYPE HLP *NEW LOT OF 4*
SIEMENS S7 24V DC SUPPLY VOLTAGE MODULE 6ES7 153-1AA02-0XB0 MISSING COVER
APPLETON 3/4" LR UNILET FORM 35 NNB
GC VALVES 24VDC SOLENOID COIL, HS4YN16 *NEW*
FESTO PRESSURE REGULATOR LR 3/8-D-MIDI P/N 173656 NNB
FALK 2.3730/2.3745 KW 5/8X5/16 HUB REBORE, 50R *NEW*
3M BLUE B ELECTRICAL SPRING CONNECTORS, *NEW LOT OF 24*
SIEMENS SWITCH WIRING UNIT 3RA1913-2A NIB
TOKYO FLOW METER CO USF200S-G10-1-A?2000
ROSEMOUNT 300S1AAE5M5 SUPERMODULE PRESSURE TRANSMITTER, NIB
ELECTROCUBE 600V 1/2W 150 OHMS SINGLE-PHASE RC NETWORKS, RG1986-7 *NEW LOT OF 2*
BALLUFF PROXIMITY SENSOR BES 516-324-E4-C-S4?-00,3 NIB
AB PILOT LIGHT NEW WITHOUT BOX 800T-PST16
JOSLYN CLARK 110/120V COIL 10A PM CONTROL RELAY, 5UU84-76 *NEW*
SCIENTIFIC TECHNOLOGIES INC, MINI SAFE/FLEX SAFE 4300B - 2
APPLETON CONDUIT BODY 1 1/4" MALL IRON FORM 35 UNILETS C125-M NIB
O-Z GEDNEY 1/2" NPT MALLEABLE IRON CONDUIT BODY, LB-150 *NEW*
REGAL 1" SET SCREW E.M.T COUPLING 713 1 LOT OF 3 NIB
OMRON DIGITAL PANEL METER K3N R-NB1A-T1
CONTRINEX CABLE CONNECT S12-FUW-020-905 NIB
THOMAS & BETTS 480VAC/250DC 60A 3P 4W EVER-LOK PLUG, F27194 *NEW*
MARSH 3.5 INCH 100 PSI 1/4 INCH NPT PAPER MACHINE GAUGE, W6048 *NEW*
COOPER 300V 3A 5P 6M MALE IN-LINE/FEMALE CONNECTOR ASSEMBLY, 5000111-589R *NEW*
MARSH INSTRUMENT 3.5" DIAL 0/30 PSI 1/4" NPT PAPER MACHINE GAUGE, W6042W3 *NEW*
MICRO SWITCH 600VAC LIMIT SWITCH, BZV6-2RN
HONEYWELL MICRO SWITCH, 9PA15 *NEW*
BEC CONTROLS 125VAC 10A .08-2.0"WC PRESSURE SWITCH, A902-1P-0QA4 *NEW*
ORTRONICS 110V CAT5 MINI-MOD MODULES, OR-62750013 *NEW LOT OF 11*
LEVITON 125V 15A 2-POLE 3-WIRE LOCKING PLUG, 4720-C *NEW SEALED*
ADALET PLM 2-7/8" NPT ARMORED CABLE CONNECTOR, JAG-250
RECHNER SENSOR KAS-70-30-S-M32 NIB
THOMAS & BETTS 250V/600VAC 30A EVER-LOK RECEPTACLE, 8004-RS *NEW*
HUBBELL 277VAC 15A 2P 3W TWIST-LOCK PLUGS, HBL4770C *NEW LOT OF 8*
TURCK MICRO FAST 250V 4.0A 4-PIN RIGHT ANGLE FEMALE CORDSET, WKB 4T-2 *NEW*
MAGENTROL 24VDC 10AMP 8000PSI @ 100°F 3/4"NPT ECHOTEL LEVEL SWITCH 910-A1A2-006
STATIC O RING 250 VAC 15A DIFFERENTIAL PRESSURE SWITCH, 101AG-EF3-N4-C1?A *NEW*
ALLEN BRADLEY 872C-D 3NN12-D4 SERIES C PROXIMITY SENSOR NNB
COOPER CROUSE-HINDS 600V 8A 6P 6' FEMALE PLUG CORDSET, X8987-4C *NEW*
TURCK * MICRO FAST CABLE * WKB 5T-6SB 5T
HUBBELL KELLEMS 3/4" SEAL-TITE CORD GRIP W/ MESH, 074-09-3513
FESTO 24V 4-PIN 90 DEGREE ANGLE CONNECTOR, 18527 *NEW*
VERSA GAUGE 2" FACE 160 PSI 1100 KPA 1/4" NPT PRESSURE GAUGE, 1301YLE4-NCS *NEW*
BALDOR HP.33 115/230V 6/3AMPS 1725RPM 48YZFRM INDUSTRIAL MOTOR 2-547-257-99 NNB
MARPOSS 99UT0429 1241434020 RING GGAUGE WITH CASE, NEW
BALDOR 120V .18 OHM PLUG-IN RESISTOR, BR0180 *NEW*
GEAR REDUCER 3842516621
UNITED ELECTRIC CONTROLS 480VAC 15A 1/4" NPT PRESSURE CONTROL SWITCH, 126 *NEW*
OHMITE 300W 5.0 OHM POWER RESISTOR, C300K5R0 *NEW*
APPLETON UNILET 1 1/2" LR FORM 35 NNB
TPC WIRE & CABLE SUPER-TREX 4 POLE 5 METER 16/4 FEMALE RECEPTACLE, 94496 *NEW*
SMC FITTINGS KQ2T11-36S SEALED
TOKUDA IONIZATON VACUUM GAUGE HFT-7, FRONT PANEL CRACKED
METAL FILM RESISTOR 2525-0000 BAG OF 4 NIB
BROWNING 2.149" PITCH 2-7/16' FLANGE 18 GROOVE GEARBELT PULLEY, 18LG100 *NEW*
MAGNETEK TRIAD 115V 60HZ FILAMENT TRANSFORMER F-40X
LEVITON 125V 15A 2-POLE 3-WIRE LOCKING PLUG, 5266-C *NEW*
CROUSE-HINDS SERIES NCGE CORD AND CABLE FITTING, NEW IN BAG
PASAR 1/4@10-50V 6.25KHz LOW VOLTAGE CURRENT TRACER CT-10
MILJOCO 30 PSI 2 BAR 1/8" NPT 1-1/2" PRESSURE GAUGE, P150803 *NEW*
APPLETON 30AMP 3W 4P POWERTITE RECCEPTACLE ADR-303
FOXBORO SPEC 200 RECORDER MODULE 220S-2F6 ST-C
AB WHITE PUSHBUTTON 800MR-QL24S LOT OF 2
ASHCROFT TYPE 200 1/2" NPT DIAPHRAGM SEAL W/ TRERICE 0-60 PSI GAUGE, C1018 *NEW*
ASHCROFT DURAGAUGE 4-1/2" 3000PSI GAUGE 45-1379-BS-04L-?3000#, NIB
AMPHENOL CIRCULAR CONNECTOR PLUG 97-3055-22-8 SIZE 22 WITH CABLE 115
TURCK 250VAC 300VDC 4.0A 4PIN MOLDED JUNCTION, VB2-RS 4.4T-1/2FKM 4.4/S651 *NEW*
LUMBERG VAD 1A-1-3-M12-5 NNB LOT OF 5
ACCUSPEC CAPACITOR 020190 220 Ohm 1/2WATT 104X122CA-002
CLARK THERMAL OVERLOAD RELAY 2535 *NEW*
FESTO FILTER REGULATOR LFR- 1/2-D-MAXI MA-50-16-1/4 NIB
OMRON S8VM-15012C POWER SUPPLY 12VDC 12.5A NIB
RELIANCE ELECTRIC M052576005T0079?16716KA APPROX 1" DIA. SHAFT 0.9 HP MOTOR, NEW
NUMATICS REGULATOR R00-02DMODEL 2-40PSI 0A4BAR NNB
KILLARK 1-1/2" HUB TYPE LB ALUMINUM CONDUIT BODIES, OLB-5 *NEW LOT OF 2*
TPC WIRE & CABLE 4 POLE FEMALE 6M CORD TREX-ONICS MICRO QUICK-CONNECT 69420 NIB
PEER CHAIN 50R X 10FT ROLLER CHAIN W/ 4 CONNECTING LINKS, NIB
TPC WIRE & CABLE 600V 3P 20FT SUPER-TREX CORD SET, 84909 *NEW SEALED*
TURCK PROXIMITY SENSOR NI10-G18-AZ3X-B?1431 60 MM NIB
ROSEMOUNT PRESSURE TRANSMITTER 1151GP6E52B2
TELEMECANIQUE PUSH BUTTON ZA2 BS54 X1 NIB
OEM SOLUTIONS MODULE 8 AMP AT 240VAC PM-35-200-4
ASCO RED HAT SOLENOID VALVE 3/8 SC8210G93 NIB
MODUTEC 3-1/2" 0-200 A-C AMPERES METER, 00-890257-001
TRERICE 160°F MAX DIAL THERMOMETER L80742 *NEW*
PHOENIX CONTACT RELAY 120VAC 2949211 ISOLATION I/O 4KV EMG 12-REL/KSR-120/?1
WOODHEAD BRAD HARRISON 250V 4A 4P 5M MICRO CHANGE CORDSET, 884030C02M050 *NEW*
VIATRAN 15VDC 4000 PSIG PRESSURE TRANSMITTER, 1042AU2BRA20
DANIEL WOODHEAD 125V 15A 2P 3W WATERTITE PLUG, 14W47 *NEW*
WOODHEAD BRAD HARRISON 250V 4A 4P 6M MICRO CHANGE CORDSET, 804000C02M060 *NEW*
BEI 3/8" SHAFT DIA. ENCODER, H25D-SS-180-ABZ?-7406R-EM16
THOMAS & BETTS PLUG 20A 125V 2W3P EVER-LOK 859CTN
CROUSE-HINDS CONDULET OUTLET BODY 1 1/4" 4253 NNB
FESTO FILTER LF-M2-G1/2-ES
BASYS CONTROLS 8-35VDC RELATIVE HUMIDITY TRANSMITTER, TH1110 *NEW*
OHMITE 25 WATTS 10K OHMS VITREOUS ENAMELED RESISTORS, 0215 *NEW LOT OF 6*
SEQUENTIAL 1/4" SHAFT DIA. ANGLE ENCODER, 25CN-360-IZ-E1S?-15V-H1F1D1FB3T?3
HOFFMAN 5.75 X 4.00 X 3.75 IN. DPB PUSHBUTTON ENCLOSURE, E-D2PBM *NEW*
APPLETON TYPE FS 3/4" NPT SINGLE GANG MALLEABLE IRON DEVICE BOX, FS-1-75 *NEW*
TOYO FAN 230 VAC 50/60HZ 12/10W UT857CG
MARSH BELLOFRAM 63MM 600 PSI 1/4" NPT GLYCERINE FILLED GAUGE, J7664P *NEW*
APPLETON CONDUIT BODY 1 1/2" MALL IRON FORM 35 UNILETS C150-M NIB
HUBBELL 125V 20A 2P 3W DUPLEX RECEPTACLE, HBL5362I *NEW*
MARTIN NO.6 QUADRA-FLEX COUPLING SLEEVE, 6EM *NEW UNOPENED*
HONEYWELL GKRA14L6A2 MICRO SWITCH LIMIT SWITCH 24VDC
PVC TUBING , ID 1/8" OD 1/4" LENGTH 100' WALL 1/16" NIB
AIMCO SULFUR DIOXIDE LEVEL TESTER S-450 105347
MAKINO TYPE RSD40-JL ROLLER CHAIN PINS, LOT OF 11, NEW IN BAG
BURNDY HYLUG 1/0 AWG 5/16 IN. STUD TERMINALS, YA25 *NEW LOT OF 10*
PRE-CON TEMPERATURE SENSORS ST-A3 *NEW, SEALED*
BRAD HARRISON 600VAC/DC 12" 5P FEMALE STRAIGHT CONNECTOR,1R500?4A20A120 *NEW*
BURKERT 0331 C 5/32 FPM NNB
NESS TBP-40-ME-S -30-100C THERMOMETER GAUGE
STEARNS 230VAC 60HZ COIL, 6-3-62306-09
TURCK EURO FAST CABLE RKG4.4T-4/S600 NIB
BRAD HARRISON MINI CHANGE MOLDED CONNECTOR APC3000 *NEW, SEALED*
INGERSOLL RAND 55PNC3 STRAIGHT PNEUMATIC AIR SHUTOFF NUTRUNNER, 1/4 HEX
ORTRONICS 110V CAT5 MINI-MOD MODULES, OR-62750013 *NEW LOT OF 10*
WESCHLER/BOWMAR ANALOG PANEL METER A2M800VV010S339?MX
SIEMENS 24VDC SURGE SUPPRESSOR, 3RT1926-1TR00 NIB
UNION 0.30A 600V PORCELAIN FUSE HOLDER 2520-388-424 1 LOT OF 4
CROUZET 81542002 SUB-BASE MOUNT RELAY, LOT OF 15, NEW IN BAG
CROUSE-HINDS TANDEM OUTLET BOX 1/2" FS17 3/4" FS27 NNB
HUBBELL SEAL-TITE INSULPRENE TRIPLE SEAL COVER, HBL6035 *NEW*
IR INGERSOLL-RAND METER DC TOOL CABLE GEA40-CORD 3M
APPLIED ROBOTICS LIMIT SWITCH W/ MOUNTING HARDWARE, 95507-B1074A *NEW*
DISC INSTRUMENTS 15VDC 3/8" SHAFT DIA. ENCODER, 702FR-100-OCLP-?TTL-SS
FLOWSERVE AUTOMAXB115S10 ACTUATOR, VELAN 1 1/2" VALVE, ACSO MP-C-089
FESTO DZH-40-50-PPVA-?S2 NNB
ABB IEC 947-5-1
DYNAMICS RESEARCH CORP. 3/8" SHAFT DIA. ENCODER, 29L-31-D13-250
MILLER 1560 PSI 2-1/2"BORE 4"STROKE HYDRAULIC CYLINDER DHV61B6B NNB
ALLTEMP SENSORS 3/4" NPT, TYPE 3 THERMOCOUPLER 1962 SER. 2
WIKA DN 150 6" PRESSURE RING NEW
MINERALLAC MINE45 CLIP FITS 3/4" EMT NIB
DISC-INSTRUMENT UNKNOWN PART NUMBER ENCODER 3/8 SHAFT
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