描述
A，B为输入逻辑变量，M为输出逻辑变量，它们之间的“与”、“或”、“非”逻辑运算关系如表1．1所示。用继电器电路或梯形图可以实现基本逻辑运算，触点的串联可实现“与”运算，触点的并联可实现“或”运算，用常闭触点控制线圈可实现“非”运算(见图1-4)。多个触点的串、并联电路可以实现复杂的逻辑运算，例如图l-3中的继电器电路实现的逻辑运算可用逻辑代数表达式表示为
ABB Resistance Detector SK663126-C / SK 663-126C
Foxboro Pressure Transmitter IDP10-D23D01C-M2L1C1K
Foxboro Pressure Transmitter IDP10-D46B21C-M1L1C1K1V
Endress+Hauser Liquiphant II Level Switch FTL 360
TRICONEX TRICON MAIN CHASSIS
Yokogawa PH402G PH converter
Foxboro Pressure Transmitter IGP20-D21B21C-M1L1C1KT
Foxboro Pressure Transmitter IGP20-D22A01C-M1L1C1KT
NEW THORBURN EXPANSION JOINT EPDM 10″ DIA, 8″ LONG
Thermo-Kinetics Temperature Probe 22-2231-61-30-410-TW
TN Technologies S Series Relay MKII 886483-3
