6SE6440-2AD27-5CA1

6SE6440-2AD27-5CA1上面这个GIF截图，是PLC和温控器之间的Modbus通信的手机快速连拍。

我在触摸屏仿真上用鼠标快速点击一个按钮。这个按钮是把温控器的工作模式在手动和PID自动模式之间来回切换，所以它是个写任务通信的反复执行。

可以看到点击的速度很快，温控器面板上的数字反应也在快速切换。就主观手感而言，执行是非常快的，滞后微乎其微，很难觉察。

但是这个写任务的执行到底消耗了多少时间呢？这执行中的细节受到哪些因素的影响？这些过程细节需要用Trace才能呈现。

下面用两张详细注释的Trace图来展示。

A、这张图是10秒钟内的整体通信场景的记录。其中可以看到周期性的2个温控器的轮询执行，和偶尔插入的临时写任务的优先执行。

6SE6440-2AD27-5CA1

Modicon PC-0984-380 Processor Module 4000

With Executive and Memory Modules? 4000

Refurbished Reliance Electric 0-52850 IRFA Module 4000

Westinghouse PC-503 CPU Module W/Memory Module 4000

Westinghouse PC-503 CPU Module W/Memory Module 4000

Allen-Bradley 809-A06E Instantaneous Trip Relay 4000

Allen-Bradley 1771-IF/B Analog Input Module 4000

SIEMENS 6ES5 482-8MA12 SIMATIC S5 DIGITAL I/O MODULE 4000

NEUNDORFER MVCII-A01 CONTROL BOARD 4000

30-Day Warranty? 0

NEUNDORFER MVCII-P02 CONTROL BOARD 4000

30-Day Warranty? 0

FINCOR Model 2611 APO Adj. DC Speed Control 2HP Max. 4000

FINCOR Model 2303 MKII DC Speed Control 2HP Max. 4000

 Love Controls Model 49 Proportioning Controller 4000

Modicon 610 MSA 210 31 M100S Cyberline Sercos Drive 4000

Superior Electric 430-PTO SLO-SYN Oscillator Drive 4000

 IAI 12ED/FD-60 INTELLIGENT ACTUATOR CONTROLLER 4000

Allen-Bradley 7300 UPJ CNC Circuit Board 4000

Microscan MS-850 FIS-0850-0001 Bar Code Scanner 4000

 Texas Instruments TI 5TI-3201 Timer/Counter Module 4000

 TENOR 763-7-0115 MODEL II STEPPER MODULE 4000

FANUC A03B-0801-C051 PT01A POSITIONING MODULE 4000

 Reliance Electric 0-54374 Relay Card Drive Module 4000

VERO PK110 TRIVOLT 115V SERVO POWER SUPPLY 4000

XYCOM 3100MT LCD FLAT PANEL WORK STATION 4000

XYCOM 3512T 12.1" TOUCHSCREEN COLOR WORKSTATION 4000

P/N: 3512-03F314003601G? 4000

Cincinnati Milacron 3-531-3280A Timer Circuit Board 4000

Refurbished By Advanced Technology Services (ATS)? 4000

Reliance Electric 802816-1RD Driver Module 4000

Siemens 6FX-1111-1AA00 System 3 Encoder Module 4000

14-Day Warranty? 4000

 Square D SYMAX 8005 LTV-101 Module 4000

Modicon 100-0037-252 CPU Control Board 4000

Reliance Electric 0-52839 TSSA Drive Module 4000

 GE Drive IC3600 AOAF2 Module IC3600AOAF2 4000

Reliance Electric 0-51874-2 SSCC Drive Module 4000

ABB YB560103-BD/4 DSQC 223 Robotic I/O Module 4000

Siemens 6FX-1111-1AA00 System 3 Encoder Module 4000

14-Day Warranty? 4000

OMRON C500-DA003 0 TO +5V D/A MODULE 4000

 Allen-Bradley 2711-M14 Color CRT Monitor 4000

Bailey Controls NBIM02 Net 90 Bus Interface Module 4000

Refurbished? 4000

MITSUBISHI FX-40DU-TK-ES MELSEC DATA ACCESS UNIT 4000

Allen-Bradley 7300 UPG CNC Circuit Board 4000

Reliance Electric 86466-57S Rectifier Stack 4000

Pentland Systems MPV904 16-Channel Analog VME Module 4000

Bailey Controls NPIM01 Network 90 Processor Interface 3520

ELECTRO CAM PLuS PS-5004-10-016 PROGRAMMABLE SWITCH 3520

OMRON 3F88L-132 CAM POSITIONER 100-240VAC 3200

Modicon PC-0984-381 Programmable Controller 3200

With Installed Executive and Memory Modules? 3200

Reliance Electric 57C492 Battery Backup Unit 803623-R 3200

 Honeywell 627-7021 48KB CMOS RAM Memory Module 3200

Honeywell RM7888 A 1027 Burner Control 3200

CONTROL TECHNIQUES R115DUE400CSDPE DUTYMAX DS MOTOR 3200

ROSEMOUNT OPM 2000 OPACITY METER/ANALYZER 3200

STI MC4700-14-1575 MICROSAFE TRANSMITTTER & RECEIVER 3200

AEG Modicon AS-B872-011 Analog Voltage Output Module 3200

Allen-Bradley 1771-IXHR/C Thermocouple/mV Input Module 3200

Allen-Bradley 1771-TCM/B Temperature Control Module 3200

AEG Modicon 110-108 Cyberline 1000 PLS4 Power Supply 3200

 Reliance Electric 0-57141 Flexpak Plus Regulator 3200

6SE6440-2AD27-5CA1