从可靠性和可维护性上看，由于电器控制系统使用了大量的机械触点，其存在机械磨损、电弧**等，寿命短，系统的连线多，所以可靠性和可维护性较差。而PLC大量的开关动作由无触点的半导体电路来完成，其寿命长、可靠性高，PLC还具有自诊断功能，能查出自身的故障，随时显示给操作人员，并能动态地监视控制程序的执行情况，为现场调试和维护提供了方便。

API Controls DM-224I-EDN Motor Controller
API Harowe HAROSYN-RCX 15BRCX-500-J23 Encoder 7000Hz 4.35V IN, 2.0V OUT
API Motion M23-23D-6204AB Hybrid PM Step Motor 100oz-in Torque Hold, 1/4" Shaft
APM Model 87 Digital Radiometer 9VDC Battery 3.5mm Jack with Soft Vinyl Case
Apollo 3TS-20-6 CompacTorque Pneumatic Actuator with Valve Point Position Sensor
Apollo 70-206-01 Ball Valve 1-1/4"
Apollo 78-204-01 Ball Valve 3/4"
Apollo 78-204-01 Ball Valve 3/4"
APPLE 27" THUNDERBOLT DISPLAY & STAND ONLY A1407 - AS IS
APPLE IPHONE 4 16GB WHITE VERIZON MOBILE SMART PHONE BLACKLISTED / AS IS
APPLETON 1/2 X 30" FLEX COUPLING EXGJH-130 EXGJH130
Appleton GRJS50 Malleable Iron Unilet 1/2"
Applied Motion 5560 Step Motor Drive Microstepping 5.5 Amps, 24-60VDC
Applied Motion HT17-075D Stepper Motor with E2-500-197-IH Encoder
Applied Motion HT17-075D-WAA Step Motor With 17PL010 Gearhead, Shaft Dia: 0.5"
Applied Motion HT17-075D-WAA Step Motor With 17PL016 Gearhead, Shaft Dia: 0.5"
Applied Motion Products 5023-122 Stepper Motor, 1/4" Shaft Dia, 1.8o Per Step
Applied Motion Products HT17-154 Stepper Motor, 4VDC 1.2Amp, 3.3 Ohm, 200 S/R
Applied Robotics CXC10F-18-150-5 Tool Change Support Frame w/ Proximity Sensor
Applikon ZB201X5200 722 Electric Shaft Stirrer, 7-12VDC / 0.2A, 440-2800 RPM
Approximately 10ft of Wire Reinforced Vinyl Hose, 6" ID, 3/4" Bend Radius
APRICORN 16GB AEGIS FLASH DRIVE USB 2.0 FLASH DRIVE W/ 256BIT AES-CBC ENCRYPTION
APW 28-238120J 230VAC 19" Fan Unit for 19" Rack
ARECONT VISION AV2255DN MEGADOME 2 2.07MP CAMERA 3.4-10.5MM VARIFOCAL LENS
Argus 1188-79-001 PC Board
Argus 1189-21-001 PC Board
Argus 1189-25-001 PC Board
Argus 1189-27-001 I/O Digital PC Board w/Cables
Argus 1189-31-001 I/O Analog PC Board w/Cables
Armored Fiber Optic Cable 12"L 3/4" down to 9/16"
ARO 104104-F01 Inline Flow Control Valve 3/8" NPT 200PSI 200°F
ARO 1321-2100-030 CO-Axial Air/Hydraulic Cylinder 3" Stroke *Rough Condition*
ARO 201-2-C 3-Way Air Control Valve, Fingertip Lever, 5/32" Tube Fittings
ARO 224-C Limit Valve, 1/8" NPT, 150PSI Max, 7.5CFM, 30-150 Operating Pressure
ARO 224-C Limit Valve, 1/8" NPT, 150PSI Max, 7.5CFM, 30-150 Operating Pressure
ARO 461-1 Palm Button Control Valve, 2-Position 3-Way, Button Color: Black
ARO 461-3 Palm Button Control Valve, 2-Position 3-Way, Button Color: Green
ARO 461-4 Palm Button Control Valve, 2-Position 3-Way, Button Color: Yellow
ARO 59180 "Flip Flop" Solenoid Valve Element
ARO 59191 Pneumatic Two Hand Anti-Tie-Down 1/8" NPT 50-125PSI *Scratched Top*
ARO 59191 Pneumatic Two Hand Anti-Tie-Down, Ports: 1/8" NPT, Pressure: 50-125psi
ARO 59192 / 59121 Pneumatic Logic Anti-Tie Down 2 Green 1 Red Pushbutton
ARO A211PD Pneumatic Valve w/ Pneumatic Pilot 4-Way 2 Position Double Action
ARO A212SD-120-A Pneumatic Valve, Pilot Operated, 2-Position 4-Way
ARO CAT33P-012-D-G Solenoid Valve, 12VDC 4.8W, 24VAC 50Hz 8.5VA/60Hz 6.9VA
ARO CAT66P-024-D-G Solenoid Valve, 3-Way 2-Position, Ports: 1/4" NPT, 24VDC
ARO CQ493-600-2 Regulator w/Gauge
ARP STAINLESS STEEL CYLINDER HEAD BOLT KIT 434-3701
ARRIS D5 UEQ DRFI QUAD QAM MOD QPM 790532 8DX4 ARCT02516
ARRIS QPM QAM OCTAL D5 UEQ 8DX4 21 DEC 2010 ARCT02516 790532
Arrow F363F5-S1 Drain Filter 250PSIG 3/8" NPT
Arrow R162 Pneumatic Regulator 1/4" NPT, 1/8" Gauge Port, 250PSI Max, 5-125PSI
ARROWHART 6866 SAFETY GRIP PLUG 20A 250V **LOT OF 5**
ARROWHART ACC430UMM30 CONTACTOR 208/240 VOLT 3 POLE 50/60HZ
Artesyn SMP/LC75/5/AS/SC Power Supply 115/230,140VA-In 75W-Out
Artisan 423 DC Flasher 24VDC 1A Time Delay:60 FPM
Artisan 438 USA Solid State Timer, 19-288VAC/DC 50/60Hz, Delay-On-Make, 1-1024s
ARUBA NETWORKS AP-205 ACCESS POINT BRAND
ARUBA NETWORKS AP-225 ACCESS POINT BRAND
ARUBA NETWORKS MIMO OUTDOOR ANTENNA KIT MA-WE2458-2ARH2 ANT-2*2-D607 7.0DB
ARUBA NETWORKS S1500 MOBILITY ACCESS SWITCH S1500-48P 48 PORTS ARSW1548
ARUBA NETWORKS SUPERVISOR CARD I 2010004D 2* 256MB RAM / 256MB COMPACTFLASH CARD
Asahi 1040N Accutrak Dual Display Monitor
Asahi 150-6 Butterfly Valve, 6" Diameter, Pressure Rating: 150psi, PVC Body
Asahi America 1609-020 Ball Valve w/1040N Accutrak Monitor *Missing Nuts*
Asahi America 1619-020 Ball Valve w/1040N Accutrak Monitor 2" Viton TU PP
Asahi America BP79PSNST Valve Actuator, 120PSI, 100 in-lbs, Ball Valve, 1-1/2"
Asahi America NW25 Strainer Valve 25.42mm (1") with Filter
Asahi AV Gate Valve, With Travel Stop Adjustment, 1/2" Socket Connections, PVC
Asahi AV V2ALVCES8025 PVC Ball Valve, Pressure Rating: 1MPa (230psi), *With Pipe
Asahi AV Valve Handle, Approx 6" Wide, 0.7" x 0.9" Oval Bore
Asahi/America 96E02401A 1 1/2" Flanged Ball Valve
Asahi/America EPDM 05100025H 3" Sediment Y Strainer
Asahi/America EPDM 1/2" PVC Duo-Block Turn Valve 150PSI
Asahi/America EPDM Manual 5/8" Two-Way Valve 150PSI at 70F Max
Asahi/America Manual 2 Way Valve 20mm EPDM Seal 150PSI
ASCEND 10 DEGREE SLEEPING BAG 33" x 75"
Asco 302116 Redhat Solenoid Valve


资讯来源：福州卓凯  

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