橫河輸入模塊AAT141-S00/T4D00
AAR181-SE0/R8S10 AAI141-SE0/A4S10 AAV141-SE0/A4S10 AAV142-SE0/A4S10 AAV542-SE0/A4S10
AAR181-SF0/R8S10 AAI141-SF0/A4S10 AAV141-SF0/A4S10 AAV142-SF0/A4S10 AAV542-SF0/A4S10
AAR181-H00/R8S10 AAI141-H00/A4S10 AAV141-H00/A4S10 AAV142-H00/A4S10 AAV542-H00/A4S10
AAR181-H50/R8S10 AAI141-H50/A4S10 AAV141-H50/A4S10 AAV142-H50/A4S10 AAV542-H50/A4S10
TC Input/RTD Input Modules (Isolated)
These modules receive signals from mV, thermocouple (TC) and RTD. They can be used in dual redundant con?guration.
Items | Speci?cations | ||
Model | AAT141 | AAR181 | |
Number of input channels | 16, isolated (*7) | 12, isolated | |
Input signal | TC: JIS C1602:1995, IEC584:1995 Type J, K, E, B(*1), R, S, T, N mV: -100 to 150 mV, -20 to 80 mV |
RTD: JIS C1604:1997, IEC751:1995 Pt100 (3-wire type)(*6) | |
Switching input signals | TC/mV can be set individually for CH1 to CH16. | CH1 to CH12 are RTD inputs. | |
Allowable input voltage | ±5 V | ±5 V | |
Withstanding voltage | Between input and system: 1500 V AC, For 1 minute | ||
Input resistance | Power ON | 2 MΩ or more | |
Power OFF | 2 MΩ or more | ||
Accuracy | TC: ±30 µV MV: ±80 µV for span (-100 to 150 mV) ±30 µV for span (-20 to 80 mV) |
RTD: ±120 mΩ | |
Allowable total resistance of signal source plus wiring |
1000 Ω or less |
40 Ω or less (wiring resistance per wire) (*2) | |
Effect of allowable signal source resistance (1000 Ω) |
±20 µV(*3) |
— | |
Reference junction compensation accuracy |
Within ±1 °C (*4) (*5) |
— | |
Measurement current | — | RTD: 1 mA | |
Temperature drift | ±80 µV/10 °C (-100 to 150 mV input) ±30 µV/10 °C (TC/-20 to 80 mV input) |
±120 mΩ/10 °C (RTD input) | |
Data update period | 1 s | ||
Burn-out | All channels can be set together. Setting: Not available/available (UP/DOWN) detection time: 60 s | ||
Maximum current consumption | 450 mA (5 V DC) | 450 mA (5 V DC) | |
Weight | 0.2 kg | ||
External connection | Pressure clamp terminal |
Voltage Output Modules (Isolated)
It can be used in dual redundant con?guration.
Items | Speci?cations |
Model | AAV544 |
Number of output channels | 16, isolated |
Output signal | -10 to 10 V |
Withstanding voltage | Between output and system: 1500 V AC Withstanding voltage, For 1 minute (*1) |
Allowable load resistance | 5 kΩ or more |
Accuracy | The larger one among ±12 mV or ±0.3 %FS |
Data update period | 10 ms |
Drift due to ambient temperature change | The larger one among ±0.1 %/10 ?C or ±10 mV/10 ?C |
Maximum current consumption | 860 mA (5 V DC) |
Weight | 0.2 kg |
External communication | Pressure clamp terminal, MIL connector cable, Dedicated cable (KS1) |
*1: The withstanding voltage for using the dedicated cable is 500 V AC (between the input signal and the system).
The withstanding voltage for using MIL connector cable depends on the electrical speci?cations of its cable.
3 人為故障
在對(duì)DCS系統(tǒng)進(jìn)行維護(hù)或故障處理時(shí),有時(shí)會(huì)發(fā)生人為誤操作現(xiàn)象,這對(duì)于經(jīng)常進(jìn)行系統(tǒng)維護(hù)或新參加系統(tǒng)檢修維護(hù)的人員來(lái)說(shuō)都是會(huì)發(fā)生的。一般在修改控制邏輯、下裝軟件、重啟設(shè)備或強(qiáng)制設(shè)備、保護(hù)信號(hào)時(shí)zui易發(fā)生誤操作事件。AAT141-S00/T4D00輕則導(dǎo)致部分測(cè)點(diǎn)、設(shè)備異常,重則造成機(jī)組或主要輔機(jī)設(shè)備停運(yùn),后果是非常嚴(yán)重的。在使用DCS的電廠、石化、化工廠,人為誤操作發(fā)生的故障在熱工專(zhuān)業(yè)中的不安全事件中占有很大比例。
4 電源故障
電源方面的問(wèn)題也較多,如備用電源不能自投,保險(xiǎn)配置不合理及DPU電源內(nèi)部故障等造成電源中斷,穩(wěn)壓電源波動(dòng)引起保護(hù)誤動(dòng)及接插頭接觸不良導(dǎo)致穩(wěn)壓電源無(wú)輸出;有的系統(tǒng)整個(gè)機(jī)柜通過(guò)一路保險(xiǎn)供所有輸入信號(hào)或一路電源外接負(fù)載很大,還有的控制電源既未接UPS又未有冗余備用。
5 SOE工作不正常
SOE的結(jié)論對(duì)事故的分析、判斷起了很重要的作用,但在現(xiàn)實(shí)中,許多電廠發(fā)生保護(hù)動(dòng)作等情況時(shí)SOE未記錄下來(lái)或記錄時(shí)間與實(shí)際情況不符。如××電廠#1機(jī)組出現(xiàn)過(guò)SOE事件順序追憶時(shí)間與實(shí)際跳閘時(shí)間不相對(duì)應(yīng),SOE時(shí)間打印瀏覽后不能返回,*跳閘原因在事件順序中不能*個(gè)反映,SOE時(shí)間順序數(shù)據(jù)不能設(shè)置等問(wèn)題。而有的電廠在幾次事故分析時(shí)發(fā)現(xiàn)SOE結(jié)論中的時(shí)序與歷史曲線中的時(shí)序有偏差,有時(shí)甚至?xí)r序顛倒,具體表現(xiàn)于同一點(diǎn)在歷史曲線和SOE中發(fā)生時(shí)間不*,且有時(shí)偏差很大,這會(huì)延誤事故分析的進(jìn)程,有時(shí)甚至誤導(dǎo)事故分析方向。SOE問(wèn)題既與系統(tǒng)設(shè)計(jì)不合理,SOE點(diǎn)沒(méi)*集中在一個(gè)DPU上有關(guān),也與系統(tǒng)硬件及軟件設(shè)計(jì)考慮不周有關(guān)。
6 干擾造成的故障
干擾造成DCS故障的事例也不少。D璐系統(tǒng)的干擾信號(hào)可能來(lái)自于系統(tǒng)本身,也可能來(lái)自于外部環(huán)境。
由于不同的DCS系統(tǒng)對(duì)接地都有嚴(yán)格的規(guī)定,一旦接地電阻或接地方式達(dá)不到要求,就會(huì)使網(wǎng)絡(luò)通信的效率降低或增加誤碼的可能,輕則造成部分功能不正常,重則導(dǎo)致網(wǎng)絡(luò)癱瘓。
電源質(zhì)量同樣影響系統(tǒng)的穩(wěn)定運(yùn)行。用于DCS系統(tǒng)的電源既要保證電壓的穩(wěn)定,也要保證在一路電源故障時(shí),無(wú)擾切換至另一路電源,否則會(huì)對(duì)系統(tǒng)工作產(chǎn)生干擾。
過(guò)程控制處理機(jī)主/備處理機(jī)之間的切換有時(shí)也會(huì)導(dǎo)致干擾。
另外,大功率的無(wú)線電通信設(shè)備如手機(jī)、對(duì)講機(jī)等在工作時(shí),極易造成干擾,危及系統(tǒng)運(yùn)行。AAR181-H50/R8D00 AAI141-H50/A4D00 AAV141-H50/A4D00 AAV142-H50/A4D00 AAV542-H50/A4D00
AAR181-H60/R8D00 AAI141-H60/A4D00 AAV141-H60/A4D00 AAV142-H60/A4D00 AAV542-H60/A4D00
AAR181-HE0/R8D00 AAI141-HE0/A4D00 AAV141-HE0/A4D00 AAV142-HE0/A4D00 AAV542-HE0/A4D00
AAR181-HF0/R8D00 AAI141-HF0/A4D00 AAV141-HF0/A4D00 AAV142-HF0/A4D00 AAV542-HF0/A4D00
AAR181-S01/R8D00 AAI141-S01/A4D00 AAV141-S01/A4D00 AAV142-S01/A4D00 AAV542-S01/A4D00