選型注意事項
S7-300PLC的選型原則是據生產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)有關參數確定。一是輸入/輸出點數(I/O點數)確定。這是確定PLC規模的一個重要依據,一定要根據實際情況留出適當余量和擴展余地。二是PLC存儲容量確定。注意當系統有模擬量信號存在或要進行大量數據處理時,其存儲容量應選大一些。
(2)系統軟硬件選擇。一是擴展方式選擇,S7-300PLC有多種擴展方式,實際選用時,可通過控制系統接口模塊擴展機架、Profibus-DP現場總線、通信模塊、運程I/O及PLC子站等多種方式來擴展PLC或預留擴展口;二是PLC的聯網,包括PLC與計算機聯網和PLC之間相互聯網兩種方式。因S7-300PLC的工業通信網絡淡化了PLC與DCS的界限,聯網的解決方案很多,用戶可根據企業的要求選用;三是CPU的選擇,CPU的選型是合理配置系統資源的關鍵,選擇時必須根據控制系統對CPU的要求(包括系統集成功能、程序塊數量限制、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,硬件組態時會發生故障出錯,而STEP7V5.0則不存在這種問題。
二、設計及使用注意事項
1. 設計注意事項
設計時主要應注意以下幾方面:
(1)PLC輸出電路中沒有保護,因此在外部電路中應設置串聯熔斷器等保護裝置,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響應延遲問題,因此在快速響應設備中應加以注意。MPI通信協議雖簡單易行,但響應速度較慢。
(3)編制控制程序時,好用模塊式結構程序。這樣既可增強程序的可讀性,方便調試和維護工作;又能使數據庫結構統一,方便WinCC組態時變量標簽的統一編制和設備狀態的統一顯示。
(4)硬件資源。要合理配置硬件資源,以提高系統可靠性。如PLC電源配電系統要配備冗余的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,系統設備要采用獨立的接地系統,以減少雜波干擾。
4 used AE Advanced Energy HFV 8000 RF Generator
ADVANCED ENERGY / AMAT HFV 8000 5kW RF Generator
Advanced Energy 3155077-001A Fixed RF Match Cool Down
AE,ADVANCED ENERGY PDX 1250 PLASMA POWER RF GENERATOR
AE Advanced Energy RF Match Network 3155169-005 B
Advanced Energy LM-1.25K RF Match Net 3152189-000H
AE ADVANCED ENERGY PDW2200 RF GENERATOR
ADVANCED ENERGY PDX 2500 RF SOURCE
Advanced Energy RFG 1250 RF Generator AE 3155027-000 S
Advanced Energy HFV 8000 RF Power Generator
Applied Materials AMAT part number 0190-22080
Advanced Energy RFX-600 RF Generator 120VT Inc Cables
ADVANCED ENERGY AZX-90 (004) RF MATCHING
AE ADVANCED ENERGY RF MATCH 3155031-037 NAVIGATOR AMAT
1110-00056 APPLIED MATERIALS RF MATCH
ADVANCED ENERGY APEX 10KW/13 RF GENERATOR WORKING
Advanced Energy RFX-600 RF Generator S/N:150353
AE ADVANCED ENERGY RF MATCH 3155031-037 1110-00056
1110-00056 APPLIED MATERIALS RF MATCH
ADVANCED ENERGY Navigator RF Bias Match 3155126-008A
Advanced Energy VHF 2060 RF GENERATOR AMAT 0920-00056
Advanced Energy RFX-600 RF Generator S/N:72806
Advanced Energy PDX 5000 RF GENERATOR 3156043-207 A
Advanced Energy RFG 3000 3155038-000 F RF Generator AE
Advanced Energy PDX 2500 Vacuum RF Power Supply
Advanced Energy FixedMatch RF Match 3155077-001A AMAT
Advanced Energy Navigator RF MATCH 3155132-001 D
AE Advanced Energy APEX 3013 RF Generator 3156113 AMAT
AE,ADVANCED ENERGY PE-5000 PLASMA POWER RF GENERATOR
ADVANCED ENERGY PE-2500 GEN RF 1500W100KHZ 3157504-012C
Advanced Energy 3155126-008 Navigator Z-Scan RF Match
ADVANCED ENERGY PE-2500 GEN, RF1500W100KHZ 3157504-012C
Advanced Energy Model RFX-600 RF Generator D
RFPP RF-5S RF Generator RF Power Plasma Advanced Energy
Advanced Energy Navigator RF Match Novellus 3155126-008
AE Advanced Energy AZX90 RF Match 3155031-004A AMAT
Advanced Energy PDP 3500 Pulsed Plasma RF Power Supply
AE Advanced Energy RFPP Mercury 1013 RF Match Novellus
Advanced Energy RF Match PN 3150274-008
Advanced Energy AE Navigator RF Match
AE Advanced Energy PDX 900-2V RF Generator 3156024-032A
AE Advanced Energy HFV 8000 RF Generator 3155083-109
RFPP Advanced Energy LF-5 RF Generator / Power Supply
Advanced Energy 3150010-001 RF Power Supply LF-10
AE Advanced Energy AZX90 RF Match 3155031-011B AMAT
Advanced Energy AZX63 RF Match 3155031-014 AMAT
AE Advanced Energy AZX90 RF Match 3155031-004C AMAT
RFPP RF20H WATERCOOLED RF GENERATOR ADVANCED ENERGY
Returns: Accepted within 14 days
Advanced Energy PDX 500 RF Power Supply: PDX500
AE Advanced Energy RF10M RF20M User Manual 5708513
Advanced Energy RF Match 13.56MHZ
Advanced Energy RF Match 13.56MHZ 10KW C3 Speed
AE Advanced Energy RF/DC Combiner PDP MDX 3156016-001
Advanced Energy AE HTCM RF Match AZX Control Module
AE Advanced Energy ATN 500 RF Match Network Auto Tuner
Advanced Energy DC Plasma RF Power Supply 2105-001
A64697 Advanced Energy LDM Plasma RF Power Supply
Advanced Energy PEP-2500 Pulsed Plasma RF Power Supply
AE Advanced Energy ATN 1000 RF Match Network Wide Range
Advanced Energy APEX 1513 RF Generator 3156111-001 LAM
Advanced Energy HFV-8000 8kW RF Generator Refurb. AE
RFPP Advanced Energy RF20S RF Power Supply 13.56 MHz
AE Advanced Energy Navigator RF Match AMAT 0190-16177
AE Advanced Energy RFG 1251 RF Generator 3155107-001 B
Advanced Energy RFX 1250 RF Generator 3155012-000-K AE
Advanced Energy RF Generator/ATN 5002-012/5021-0?01
Advanced Energy PDX 900-2V RF Generator 3156024 AMAT
RFPP Advanced Energy LF-5 RF Power Supply: 50-460 kHz
Advanced Energy AE LM-1.25K RF Match Network Controller
Advanced Energy RFX 1250 RF 13.56 MHz Power Supply Rblt
AE Advanced Energy Navigator RF Match AMAT 0190-15167
AE Advanced Energy RFXII 3K RF Generator 3155047-000D
Advanced Energy PDX 500 RF Plasma Generator
|