3BHE014070R0101控制器卡件,3BHE014070R0101使用進(jìn)展
四個通道中每個通道的轉(zhuǎn)換速度為半毫秒。這提供了一個任何通道的兩毫秒更新率。轉(zhuǎn)換信號的分辨率為12位任意范圍內(nèi)的二進(jìn)制（4096中的1部分）。%AI寄存器中的用戶數(shù)據(jù)為16位2補碼格式。將A/D轉(zhuǎn)換器的12位放入%AI數(shù)據(jù)中文字如下所示。電流輸入和A/D數(shù)據(jù)之間的關(guān)系轉(zhuǎn)換器如圖3-14和3-15所示。如果電流源反向輸入，或小于電流范圍的低端，然后，模塊將輸出與電流范圍低端對應(yīng)的數(shù)據(jù)字（0000H，單位：AI）。
3BHE014070R0101控制器卡件如果輸入的輸入超出范圍（即大于20 mA），則A/D轉(zhuǎn)換器將輸出至滿標(biāo)度（對應(yīng)于7FF8H，單位為%AI）。輸入比例如下圖所示。模塊的輸入保護(hù)足以保證在性能降低的情況下運行高達(dá)200V共模。該模塊提供外部電氣隔離通過使用光學(xué)隔離在現(xiàn)場布線和背板之間產(chǎn)生噪聲。為了將電容性負(fù)載和噪聲降至最低，模塊的所有現(xiàn)場連接應(yīng)使用優(yōu)質(zhì)絞合屏蔽儀表電纜接線。防護(hù)罩可以是連接到COM或GND。COM連接提供對模塊中的模擬電路。接地連接提供對基板（框架）的訪問接地）。當(dāng)模塊的電源工作時，面板頂部的LED亮起。主要模塊的電源是由PLC電源提供的隔離+24 VDC電源。該電壓通過逆變器/調(diào)節(jié)器傳輸，為模塊提供工作電壓。該模塊還消耗PLC電源+5 VDC輸出的電力，以驅(qū)動隔離電路。該模塊可以安裝在90-30系列PLC系統(tǒng)。見第3-11頁，以確定模擬電流輸入的數(shù)量可安裝在系統(tǒng)中的模塊。
Conversion speed for each of the four channels is one-half millisecond. This provides an
update rate of two milliseconds for any channel. Resolution of the converted signal is 12 bits
binary (1 part in 4096) over either range. User data in the %AI registers is in 16-bit 2’s
complement format. The placement of the 12 bits from the A/D converter in the %AI data
word is shown below. The relationship between the current input and the data from the A/D
converter is shown in Figures 3-14 and 3-15.If the current source is reversed into the input, or is less than the low end of the current range,
then the module will output a data word corresponding to the low end of the current range
(0000H in %AI). If an input that is out of range is entered (that is, it is greater than 20 mA), the
A/D converter will output up to full scale (corresponding to 7FF8H in %AI).
Input scaling is shown in the next figureInput protection for the module is sufficient to guarantee operation with reduced performance
with up to 200V common-mode. The module provides electrical isolation of externally
generated noise between field wiring and the backplane through the use of optical isolation.
To minimize the capacitive loading and noise, all field connections to the module should be
wired using a good grade of twisted, shielded instrumentation cable. The shields can be
connected to either COM or GND. The COM connection provides access to the common of the
analog circuitry in the module. The GND connection provides access to the baseplate (frame
ground).
An LED at the top of the faceplate is ON when the module’s power supply is operating. The main
power source for the module is the isolated +24 VDC power supplied by the PLC power supply.
This voltage is routed through an inverter/regulator to provide the operating voltage for the module.
