選型注意事項

  S7-300PLC的選型原則是據(jù)生產(chǎn)工藝所需的功能和容量進行選型，并考慮維護的方便性、備件的通用性，以及是否易于擴展和有無特殊功能等要求。選型時具體注意以下幾方面：

  (1)有關(guān)參數(shù)確定。一是輸入/輸出點數(shù)(I/O點數(shù))確定。這是確定PLC規(guī)模的一個重要依據(jù)，一定要根據(jù)實際情況留出適當(dāng)余量和擴展余地。二是PLC存儲容量確定。注意當(dāng)系統(tǒng)有模擬量信號存在或要進行大量數(shù)據(jù)處理時，其存儲容量應(yīng)選大一些。

  (2)系統(tǒng)軟硬件選擇。一是擴展方式選擇，S7-300PLC有多種擴展方式，實際選用時，可通過控制系統(tǒng)接口模塊擴展機架、Profibus-DP現(xiàn)場總線、通信模塊、運程I/O及PLC子站等多種方式來擴展PLC或預(yù)留擴展口;二是PLC的聯(lián)網(wǎng)，包括PLC與計算機聯(lián)網(wǎng)和PLC之間相互聯(lián)網(wǎng)兩種方式。因S7-300PLC的工業(yè)通信網(wǎng)絡(luò)淡化了PLC與DCS的界限，聯(lián)網(wǎng)的解決方案很多，用戶可根據(jù)企業(yè)的要求選用;三是CPU的選擇，CPU的選型是合理配置系統(tǒng)資源的關(guān)鍵，選擇時必須根據(jù)控制系統(tǒng)對CPU的要求(包括系統(tǒng)集成功能、程序塊數(shù)量限制、各種位資源、MPI接口能力、是否有

  PROFIBUS-DP主從接口、RAM容量、溫度范圍等)，并好在西門子公司的技術(shù)支持下進行，以獲得合理的選型;四是編程軟件的選擇，這主要考慮對CPU的支持狀況，我們的體會是：STEP7V4.0對有些型號的CPU不支持，硬件組態(tài)時會發(fā)生故障出錯，而STEP7V5.0則不存在這種問題。

  二、設(shè)計及使用注意事項

  1. 設(shè)計注意事項

  設(shè)計時主要應(yīng)注意以下幾方面：

  (1)PLC輸出電路中沒有保護，因此在外部電路中應(yīng)設(shè)置串聯(lián)熔斷器等保護裝置，以防止負載短路造成PLC損壞。熔斷器容量一般為0.5A。

  (2)PLC存在I/O響應(yīng)延遲問題，因此在快速響應(yīng)設(shè)備中應(yīng)加以注意。MPI通信協(xié)議雖簡單易行，但響應(yīng)速度較慢。

  (3)編制控制程序時，好用模塊式結(jié)構(gòu)程序。這樣既可增強程序的可讀性，方便調(diào)試和維護工作;又能使數(shù)據(jù)庫結(jié)構(gòu)統(tǒng)一，方便WinCC組態(tài)時變量標(biāo)簽的統(tǒng)一編制和設(shè)備狀態(tài)的統(tǒng)一顯示。

  (4)硬件資源。要合理配置硬件資源，以提高系統(tǒng)可靠性。如PLC電源配電系統(tǒng)要配備冗余的UPS不間斷電源，以排除停電對全線運行的不利影響。又如對電機的控制回路要進行繼電器隔離，以消除外部負載對I/O模塊的可能損壞。另外，系統(tǒng)設(shè)備要采用獨立的接地系統(tǒng)，以減少雜波干擾。

 NIB VEXTA C8384-9212H C83849212H STEPPING MOTOR 2 PHASE 1.8* / STEP 4.4A 2.5V
1 PC  VEXTA RKD514L-C servo drive Tested
1 PC Used AXHD15K VEXTA stepper driver
1 PC Used AXHD30K VEXTA stepper driver
1 PC Used VEXTA Dongfang Motor Vibration Damper D6CL-6.3F
1 PC Used Vexta Oriental Motor UDK5107N In Good Condition
1 PC Used Vexta PCB AXHD100K In Good Condition
1 PC Used Vexta UDK5114N In Good Condition
1 PC VEXTA RKD514L-C servo drive Tested
1 PC VEXTA Servo Drive RKD514L-A Tested
1 PC VEXTA Stepper Motor Driver RC-204A Tested
1 PCS   VEXTA stepper driver   CSD5814N   tested
1 PCS   VEXTA stepper driver  CSD2112-P   tested
1 PCS   VEXTA stepper driver  CSD2120-P   tested
1 PCS   VEXTA stepper driver  CSD2120P2   tested
1 PCS   VEXTA stepper driver  CSD5814N-P   tested
1 PCS   VEXTA stepper driver CMD2112P   tested
1 PCS   VEXTA stepper driver CSD5807N    tested
1 PCS   VEXTA stepper driver CSD5807N-P  tested
1 pcs  VEXTA   Motor SD5107P2  tested
1 pcs  VEXTA  Motor PK243A1-SG10  tested
1 pcs  VEXTA drive SD5107 board  Tested
1 PCS NEW IN BOX VEXTA Oriental Governor TMP-1
1 pcs used Dongfang VEXTA stepping motor driver 2-PHR5E DRIVER UD2115B
1 pcs VEXTA 2.8A CSD2120-P   stepper motor driver tested
1 pcs VEXTA 2.8A CSD2120-P stepper motor driver tested
1 pcs VEXTA CSD5807N-P 0.75A   stepper motor driver tested
1 pcs VEXTA CSD5807N-P 0.75A stepper motor driver tested
1 pcs VEXTA CSD5814N-P    stepper motor driver tested
1 pcs VEXTA CSD5814N-P stepper motor driver tested
1 pcs VEXTA drive SD5107 board Tested
1 PCS VEXTA five-phase stepper driver DFC5103P in good condition
1 PCS VEXTA five-phase stepper driver UDX5107N 0.75A 100V in good condition
1 pcs VEXTA Motor PK243A1-SG10 tested
1 pcs VEXTA Motor SD5107P2 tested
1 PCS VEXTA Oriental BLHD15K DC24V Brushless DC Motor Driver in good condition
1 PCS VEXTA Oriental driver AXHD15K in good condition
1 PCS VEXTA stepper driver CMD2112P tested
1 PCS VEXTA stepper driver CSD2109-P in good condition
1 PCS VEXTA stepper driver CSD2112-P tested
1 PCS VEXTA stepper driver CSD2120-P tested
1 PCS VEXTA stepper driver CSD2120P2 tested
1 PCS VEXTA stepper driver CSD5807N tested
1 PCS VEXTA stepper driver CSD5807N-P tested
1 PCS VEXTA stepper driver CSD5814N tested
1 PCS VEXTA stepper driver CSD5814N-P tested
1 product rating- C173376 Lot 4 Vexta PK266-01B 2-Phase 1.8°/Step Stepping Motor (DC1A, 7.4Ω)
1 product rating- GATES 3VX400 SUPER HC VEXTA POWERBAND BELT
1 product rating- ONE USED VEXTA PH265M-31
1 product rating- ONE Vexta 2-Phase Stepping Motor Model PK264-02A
1 product rating- Oriental Motor ASD18A-K Vexta AlphaStep Closed Loop Motor Driver
1 product rating- Oriental Motor ASD18A-K Vexta AlphaStep series Closed Loop Motor Driver
1 product rating- ORIENTAL MOTOR PH265M-31 / PH265M31 (USED TESTED CLEANED)
1 product rating- Oriental Motor PK264-02A Vexta Stepping Motor 2-Phase 2Amp 1.4Ω PK26402A
1 product rating- ORIENTAL MOTOR PK545-NB / PK545NB (USED TESTED CLEANED)
1 product rating- ORIENTAL MOTOR UDX5114N / UDX5114N (REPAIR EVALUATION ONLY)
1 product rating- ORIENTAL MOTOR VEXTA PK266-01B STEPPING MOTOR UNIPOLAR 2 PHASE
1 product rating- ORIENTAL VEXTA STEPPING MOTOR UNIT PK264-02A 2- PHASE DC 2A 1.8/STEP
1 product rating- Vexta (Oriental Motor Co.), Model PK266-01B, Stepping Motor, DC 1A, 7.4 Ohm
1 product rating- Vexta 2 Phase Stepping Motor - PH265M-31
1 product rating- Vexta 2 Phase Stepping Motor 1/8" Step PK266-01B
1 product rating- VEXTA 2phase Oriental stepper drive CSD2109-P
1 product rating- Vexta PH265M-31 2-Phase Stepping Motor, DC6V, 0.85A/Phase
1 product rating- VEXTA PH265M-31 Stepping Motor, 2 Phase 0.9 degrees Per Step 6 Volt DC
1 product rating- Vexta PK244PA 2-Phase Stepping Motor DC 1.2A
1 product rating- VEXTA PK266-01B Stepping Motor 2-Phase 1.8o/Step 1ADC 7.4Ohm PK266-01B *NEW*
1 product rating- Vexta Stepping Motor PK266-01B w/USDigital E3-2500-250-I-D-D-B Encoder
1 x Vexta PH266-02 2 Phase Stepping Stepper Motor 1.8 deg/step DC 6v  1.2 AMP
1 x Vexta PH266-02 2 Phase Stepping Stepper Motor 1.8 deg/step DC 6v 1.2 AMP
1.0 out of 5 stars.
182698 New-No Box, Oriental K0177-M Vexta Brushless DC Motor 60W, 2000r/min
193316 New-No Box, Vexta A5246-9412K Stepper Motor, 2 Phase, 2.1A
1Pair New VEXTA EIC4081 EIC4091 ZIP-15  #F4594 CY
1Pair New VEXTA EIC4081 EIC4091 ZIP-15 #F4594 CY
1Pair New VEXTA EIC4081 EIC4091 ZIP-15 #F4594 CY 
1PC   used Vexta 2-Phase Driver UDK2120 Tested
1PC  USED VEXTA MSP101 Driver
1pc  Used VEXTA MSP101 Driver Tested
1PC  Used VEXTA Oriental motor speed regulator SG8030J
1PC  Used VEXTA Oriental motor stepping PK566-NB
1PC NEW VEXTA  SBR11-ZP
1PC NEW vexta  SS22M-SSSD
1pc NEW VEXTA governor DSP501M
1PC NEW VEXTA SBR11-ZP
1PC NEW vexta SS22M-SSSD
1pc Omron Proximity Switch TL-N5ME2 10-30VDC 2M
1pc USED    VEXTA drives MSP101        #TT2
1pc used  VEXTA  CSD2112-P
1PC USED  VEXTA 2phase Oriental stepper drive CSD2109-P
1PC USED Eastern VEXTA drive CSD2112-P
1pc USED FOR VEXTA STEP MOTOR PK545-NBC-C25 ,Without wire #T86m YS
1PC Used Good VEXTA ASD13C-A #T94R YS yh
1PC Used Japan Eastern VEXTA 28 Series 1.8 degree 0.95A Double Out Axis #w2916wx
1pc USED Oriental Motor Super Vexta UDX5107N 5-Phase Stepping Motor Amplifier
1PC Used Oriental VEXTA five phase stepper drivers plate PMD03C tested
1pc USED Super Vexta 5-Phase Motor Driver Model UDX5107 Tested Good
1pc USED Super VEXTA UDX5114 5-PHASE Servo Driver Tested
1pc USED Super VEXTA UDX5114 5-PHASE Servo Driver Tested
1PC used Vexta 2-Phase Driver UDK2120 Tested
1PC USED VEXTA 2phase Oriental stepper drive CSD2109-P
1PC Used Vexta 2-Phase Stepping Motor Model PK264-02A Tested
1pc USED Vexta 5 phase Stepping Driver Motor DFC1507 Tested with Warranty
1PC USED VEXTA AXHD30K 24VDC Motor Driver Tested Good
1Pc Used Vexta AXUD40C ms
1PC Used VEXTA AXUD40C tested
1pc used VEXTA C7325-9012
1PC USED VEXTA CSD2109-P Oriental 2-phase Stepper Driver Tested Good 24-36V 1.4A
1pc used VEXTA CSD2112-P
1PC USED VEXTA CSD2120-P Oriental Stepper Motor Driver (CSD2120P) 2.8A Good
1PC Used VEXTA CSD5814N-P Oriental Stepper Driver (CSD5814NP)
1pc used VEXTA drive AXHD30K
1pc used VEXTA drive CSD5714B
1PC Used VEXTA drive MSP-1W
1PC Used VEXTA Driver ASD18B-K
1pc USED VEXTA drives MSP101 #TT2
1pc USED VEXTA drives MSP-2W
1pc USED VEXTA drives MSP-2W
1PC used Vexta Electric machinery 0GN60K
1PC used Vexta Electric machinery 0GN60K
1PC USED VEXTA MC-S0514-L
1PC USED VEXTA MC-S0514-L
1PC Used VEXTA Motor PK243-01B tested
1PC used VEXTA Motor PK566-NB  #fi
1PC used VEXTA Motor PK566-NB #fi
1PC USED VEXTA MSP101 Driver
1PC used VEXTA MSP101 Driver Tested
1PC used VEXTA MSP101 Driver Tested Free Shipping
1PC used Vexta MSP301N Speed Controller
1PC used Vexta MSP301N Speed Controller
1PC Used VEXTA Oriental drive CSD2112-P
1PC Used Vexta Oriental Motor 5 Phase Driver CSD5814N-P
1PC USED Vexta Oriental Motor CSD5814N-P  Drive card
1PC USED Vexta Oriental Motor CSD5814N-P Drive card
1PC used VEXTA Oriental Motor Drives ASD13C-A Tested
1PC used VEXTA Oriental Motor Drives ASD13C-A Tested
1PC Used Vexta Oriental Motor PK564AN-TG10 Stepping Motor Tested
1PC Used VEXTA Oriental motor speed regulator SG8030J
1PC Used VEXTA Oriental motor stepping PK566-NB
1PC USED Vexta Oriental Motor UDK5107N
1PC USED Vexta Oriental Motor UDK5107N
1PC USED VEXTA ORIENTAL SG8030J
1PC used VEXTA ORIENTAL SG8030J #fl
1PC USED VEXTA Oriental stepper drives MSP-2W
1PC Used Vexta Oriental Stepping Motor PK566-NA
1PC USED VEXTA PH265M-31
1PC Used VEXTA PH265M-31 tested
1PC Used VEXTA PK266-03A
1PC USED VEXTA PK545-NA-C21 5-phase Stepping Motor Tested
1PC USED VEXTA PK566AW Stepping Motor #T85M YS
1PC Used VEXTA Servo Driver RKD514L-C
1PC USED VEXTA SG8030J 24V #P2389 YL
1PC USED VEXTA stepper driver CMD2109P board type
1PC Used VEXTA Stepper Driver DFC5107P Tested Good Condition
1PC Used VEXTA Stepper Driver DFC5107P Tested Good Condition
1PC used VEXTA Stepper Driver PMD07U
1PC USED VEXTA Stepping driver CSD2112-P
1PC USED VEXTA Stepping driver CSD2112-P fast ship#XR
1PC USED VEXTA stepping driver PMD07U
1PC Used VEXTA Stepping motor motor PK266-03A
1Pc Used Vexta TMP-1 ic
1pc used VEXTA UDK5107N   #TT2
1pc used VEXTA UDK5107N #TT2
1PC used VEXTA UDX5114   #1
1PC used VEXTA UDX5114 #1
1pc VEXTA  5 phase stepper driver UDX5107N supporting PH569-A 10 lines  #F334 CY
1Pc Vexta 2IJ3GB-A Used nc
1PC VEXTA 2phase Oriental stepper drive CSD