描述

循環(huán)和跳步都屬于選擇序列的特殊情況。對選擇序列和并行序列編程的關(guān)鍵在于對它們的分支和合并的處理，轉(zhuǎn)換實現(xiàn)的基本規(guī)則是設(shè)計復(fù)雜系統(tǒng)梯形圖的基本準(zhǔn)則。與單序列不同的是，在選擇序列和并行序列的分支、合并處，某一步或某一轉(zhuǎn)換可能有幾個前級步或幾個后續(xù)步，在編程時應(yīng)注意這個問題。

1．選擇序列的編程

（1）使用STL指令的編程

如圖5-35所示，步S0之后有一個選擇序列的分支，當(dāng)步S0是活動步，且轉(zhuǎn)換條件X0為“1”時，將執(zhí)行左邊的序列，如果轉(zhuǎn)換條件X3為“1”狀態(tài)，將執(zhí)行右邊的序列。步S32之前有一個由兩條支路組成的選擇序列的合并，當(dāng)S31為活動步，轉(zhuǎn)換條件X1得到滿足，或者S33為活動步，轉(zhuǎn)換條件X4得到滿足，都將使步S32變?yōu)榛顒硬?，同時系統(tǒng)程序使原來的活動步變?yōu)椴换顒硬健?/p>

歐美品牌停產(chǎn)的，常用的“PLC”備品備件

我司產(chǎn)品應(yīng)用于以下領(lǐng)域：

1,《發(fā)電廠DCS監(jiān)控系統(tǒng)》

2,《智能平鋼化爐系統(tǒng)制造》

3,《PLC可編程輸送控制系統(tǒng)》

4,《DCS集散控制系統(tǒng)》
?
5,《智能型消防供水控制系統(tǒng)》

6,《化工廠藥液恒流量計算機控制系統(tǒng)》

7,《電氣控制系統(tǒng)》造紙,印染生產(chǎn)線,變電站綜合自動化控制系列

本特利，英維思，伍德沃德，?？怂共_、西屋、瑞恩、施耐德莫迪康、ABB、AB、西門子、摩托羅拉、GE發(fā)那科、安川、博世力士樂，ACSO，力士樂等各大品牌的DCS系統(tǒng)配件，機器人系統(tǒng)配件，大型伺服系統(tǒng)備件。

Woodward 8236-043 Interface 43027

Woodward 8236-144 Light Panel

Woodward 8236-144D Light Panel

Woodward 8238-002 505E Bulkhead

Woodward 8238-007 505 Bulkhead

Woodward 8238-008 505 Flush Mount

Woodward 8238-009 505E Bulkhead

Woodward 8239-001 DSM Synchronizer

Woodward 8239-002 DSM Synchronizer

Woodward 8239-005 DRFD

Woodward 8239-006 Digital Remote Final Driver

Woodward 8239-007 Digital Remote Final Driver

Woodward 8239-008 Digital Remote Final Driver

Woodward 8239-015 Digital Remote Final Driver

Woodward 8239-016 DRFD CONTROL ASSEMBLY

Woodward 8239-939

Woodward 8240-084 EGB10C governor

Woodward 8250-022 remote servo

Woodward 8250-226 EG10P p/n A8250-226

Woodward 8250-421 EG3P oil motor

Woodward 8250-501 actuator

Woodward 8250-570

Woodward 8250-807 TA-20 Actuator

Woodward 8250-818 Governor

Woodward 8256-021 EPG Actuator

Woodward 8270-092 EG-A Control Box

Woodward 8270-122 2301 Power Supply,p/n

Woodward 8270-201

Woodward 8270-741 MOTOR OPERATED POTENTIOMETER

Woodward 8270-758 2301 SIGNAL CONVERTER

Woodward 8270-768 2301 AMPLIFIER

Woodward 8271-147 Load Sensor

Woodward 8271-467 2301 Load Share and Speed Control

Woodward 8271-472 2301 Load Sharing&Speed Control

Woodward 8271-652 2301 Load Share and Speed Control

Woodward 8271-674 Power Supplies

Woodward 8271-872 Import/Export Control

Woodward 8272-385 SPM Synchronizer

Woodward 8272-394 Real Power Sensor

Woodward 8272-447 Motor Operated Pot

Woodward 8272-464

Woodward 8272-684

Woodward 8272-684

Woodward 8272-695 Real Power Sensor

Woodward 8272-720 Real Power Sensor

Woodward 8272-781A Real Power Sensor

Woodward 8273-041 ATLAS SC

Woodward 8273-276 377A7823P001,Atlas PC 2×4 Sc w/act,LV

Woodward 8280-071 Hydraulic Pump

Woodward 8280-415 Digital Speed Control

Woodward 8280-505 723 Plus

Woodward 8290-195 Flo-Tech Speed Control

Woodward 8291-020 EHPC

Woodward 8301-633 MicroNet

Woodward 8405-020

Woodward 8406-113 EGCP-3 DIGITAL CONTROL

Woodward 8406-121 EGCP-2

Woodward 8434-246 Main Chassises w/LED&P.B

Woodward 8512-135

Woodward 8516-038

Woodward 8516-039 TG 13

Woodward 8516-042 4000 RPM CCW

Woodward 8516-051 TG-13E,4000 RPM,CCW MS CONN

Woodward 8516-068 TG-13E Actuator,Pressure Drive

Woodward 8516-076 TG-13A

Woodward 8570-412 PG Dial Governor,p/n C8570-412

Woodward 8575-241

Woodward 8575-377

Woodward 8580-064 Tachometer CIT Sensor

Woodward 8580-069 On Engine Gearbox Hydraulic Pump for Metering Valves

Woodward 8580-071 Engine Gearbox Hydraulic Pump

Woodward 8580-085 Engine Gearbox Hydraulic Pump

Woodward 8580-086 Hydraulic Pump

Woodward 8900-067 Sensor

Woodward 8901-457 CPC

Woodward 8901-881 Fuel/Water Valve

Woodward 8904-289 Valve

Woodward 8904-484 Gas Shutoff Valve with Suppression

Woodward 8904-773 Control 8904-881,9902-002

Woodward 8915-004 1907 Liquid valve with TM-55 Actuator

Woodward 8915-005 3103 Gas Valve with TM-55 Actuator

Woodward 8915-011 Control Valve-TM55P/3103 Low Temp Gas Fuel

Woodward 8915-024 Liquid Fuel Valve

Woodward 8915-046 Control Valve-TM55P/1907 Liq

Woodward 8915-075 Control Valve-TM40LP/3151A Water

Woodward 8915-094 Control Valve-TM55P/3103 High Temp Gas Fuel

Woodward 8915-103 Control Valve-TM40/Liquid LP

Woodward 8915-111

Woodward 8915-1146 3103/EM35 GAS VALVE