| 詳細(xì)參數(shù) | |||
|---|---|---|---|
| 品牌 | HIMA | 型號 | F8627X,984862765 |
| 結(jié)構(gòu)形式 | 模塊式 | 安裝方式 | 控制室安裝 |
| LD指令處理器 | 硬PLC | 加工定制 | 否 |
HIMA F8627X 984862765
最初研制生產(chǎn)的 PLC主要用于代替?zhèn)鹘y(tǒng)的由繼電器接觸器構(gòu)成的控制裝置，但這兩者的運(yùn)行方式是不相同的：
(1)繼電器控制裝置采用硬邏輯并行運(yùn)行的方式，即如果這個(gè)繼電器的線圈通電或斷電，該繼電器所有的觸點(diǎn)（包括其常開或常閉觸點(diǎn)）在繼電器控制線路的哪個(gè)位置上都會立即同時(shí)動作。
(2)PLC的CPU則采用順序邏輯掃描用戶程序的運(yùn)行方式，即如果一個(gè)輸出線圈或邏輯線圈被接通或斷開，該線圈的所有觸點(diǎn)(包括其常開或常閉觸點(diǎn))不會立即動作，必須等掃描到該觸點(diǎn)時(shí)才會動作。
為了消除二者之間由于運(yùn)行方式不同而造成的差異，考慮到繼電器控制裝置各類觸點(diǎn)的動作時(shí)間一般在 100ms以上，而PLC掃描用戶程序的時(shí)間一般均小于100ms，因此，PLC采用了一種不同于一般微型計(jì)算機(jī)的運(yùn)行方式---掃描技術(shù)。這樣在對于I/O響應(yīng)要求不高的場合，PLC與繼電器控制裝置的處理結(jié)果上就沒有什么區(qū)別了。
An electronic failure most commonly results in a display that will not turn on, which makes being able to identify that the display is properly wired important. Obvious faults like missing digits, missing segments, constant indication, etc are easier to diagnose.
Problems that AC powered indicators exhibit usually are the result of improper scaling, incorrect wiring, or electronic failure. A display that is improperly scaled will react to the 4/20mA signal, moving up and down in a predictable way, but not displaying the proper values for the loop. Correcting this requires identifying the range of the 4/20mA transmitter and scaling the display to these values.
The fact that the indicator is powered introduces another fault condition. If the display indicates a value below the 4mA scaling point by roughly -25% of the span, one can be sure that the loop current is not passing through the indicator. For instance an indicator scaled 0.0 to 23.1 will indicate approximaby -5.7 with no current going through it.
HIMA F8650E
HIMA K9203
HIMA K9203
HIMA F8627X
HIMA F8627X
HIMA F3236
HIMA F3236
HIMA F3330
HIMA F6217
HIMA F7126
HIMA F7553
HIMA F3 AIO 8/4 01
HIMA F3 DIO 8/8 01
HIMA F35
HIMA F35
HIMA F35
HIMA F8652X
HIMA F8652X
HIMA Z7116
HIMA Z7116
HIMA Z7116
HIMA Z7116
HIMA Z7138
