为了简洁明了,图中只绘出了一路蒸汽与微机的连接原理图。当测量回路增加时,只要相应增加A/D转换卡的输入路线即可。压力变送器和差压变送器、温度变送器可采用国产Ⅲ型或1151系列、EK系列。变送器采用二线制输出为4～20mA电流,各变送器输出4～20mA电流流过250Ω标准电阻后,产生1～ For the sake of conciseness, only the schematic diagram of steam and microcomputer connection is drawn in the figure. When the measurement loop increases, as long as a corresponding increase in the A / D conversion card input route can be. Pressure transmitters and differential pressure transmitters, temperature transmitters can be made of type Ⅲ or 1151 series, EK series. Transmitter with two-wire system output 4 ~ 20mA current, the transmitter output 4 ~ 20mA current flow through the 250Ω standard resistor, resulting in 1 ~